Trawl hauls are how fishing is conducted. A large net is dropped into the water for a specific amount of time. By catching exactly what is in the ocean, the acoustic backscatter can be identified (what the various colored pixels on the echograms represent). Below is an echogram on the screen, the black line is the path of the trawl through the backscatter, the little red circle indicated where the camera was, and the picture at left is pollock passing by the camera and into the back of the net at that point.
Samples of pollock and other organisms can be studied and other biological data collected. By counting, measuring, and weighing the pollock and other animals caught in each haul, calculations can estimate the amount of fish in a given area. Acoustic data can be used to determine the number of fish by dividing the measured backscatter by the backscattered energy from one fish (target strength, discussed in the last blog). That gives the number of fish:
To get the backscatter from one fish for the above calculation, we need to know the size and species of the fishes. The trawl provides that information. In the fish lab, species including pollock are identified, lengths are taken, and the number of fish at each length is entered in the computer. Also, the animals including pollock are weighed and a mean weight is determined. The number of fish computed from the acoustic and trawl data multiplied by the mean weight of a fish equals the biomass of the fish (total weight of the population in a given area).
The fisheries biologists developed the software used for all these calculations. This information coupled with the echograms can answer those earlier questions…Where are the pollock in the Bering Sea? How many are there? How big are they? How many adult pollock are there (fish that can be caught) and how many young pollock are present (providing information about future availability and how healthy the population is)?
When I first boarded the ship, I asked the fisheries biologists how they would describe what they do. They responded that they count fish, it’s not rocket science. But you know what? It kind of is!
What is this information used for?
This information is used to manage the Pollock fishery. Numerical data is given to the entities that set the fishing quotas for the Bering Sea area. Quotas are then divided up between the commercial and individual fishing companies/boats. Once fishermen reach these quotas they must stop fishing. This protects the fishery to ensure that this food source will be healthy and strong for years to come. A similar example from my home state is that of the Illinois is the Department of Conservation. One of their responsibilities is to manage the deer population. Then they can determine how many deer can be harvested each season that still allows for the deer population to thrive.
In my last blog post, I talked about preparing for and “weathering the storm”. As with most things at sea and on land, things don’t always turn out as we plan. The stormy weather began with wave heights between 8-10 feet. The ship continually rocked back and forth making walking and everything else difficult. You can tell the experienced sailors because they were much more graceful than I was. I held on to every railing and bolted down piece of furniture that I could. And even then, I would forget and place a pen on the table, which immediately rolled off. While eating I held onto my glass and silverware because as I ate and placed my knife on my plate it rolled off. Dressing was a balancing act, which I was not good at. I finally figured out it was better if I sat in a chair. Luckily for me, my patch for seasickness worked.
While I was sitting in the mess hall (dining room) an alarm rang. The engineers got up read the screen and left. The decision was made by the acting CO (Commanding Officer) that we would have to go back to Dutch Harbor. And now, as I write this, we are docked in Dutch Harbor waiting for word about the status of our voyage. Out here in Dutch Harbor, everything must be shipped in. We wait until parts and people are flown in. The fisheries biologists also have to determine the validity of the data collected on such a short voyage. They also must decide in a timely matter, can this data collection continue after returning to port?
For me, I am holding out hope that all these factors are resolved so that we can go back out to sea. Since November when I turned in my application, this voyage has been such a focal point of my life. If it doesn’t work out (I’ll try not to cry), I will still have had the adventure and learning experience of a lifetime. So here’s hoping……
What kinds of fish live in the Bering Sea? How many pollock are in the Bering Sea? Where are the pollock in the Bering Sea? How big are the pollock in the Bering Sea?
Those are just a few of the questions that the fisheries biologists on NOAA Ship Oscar Dyson work to answer during each voyage. In my last blog, I talked about the need to manage the pollock fishery in order to protect this important ocean resource because it provides food for people all over the world. It is important, then, to be able to answer the above questions, in order to make sure that this food source is available each year.
How do they do it? There are two main sources of information used in the Acoustics-Trawl (or Echo Integration Trawl) survey to determine the abundance and distribution of pollock in a targeted area of the Bering Sea. One is acoustics data, and the other is biological-trawl data.
Acoustic data is continuously collected along a series of parallel transects with a Simrad EK60 scientific echo integration system incorporating five centerboard-mounted transducers (18-, 38-, 70-, 120-, and 200- kHz). In other words: There are 5 sound wave producers (transducers) attached to the bottom of the ship, each one emitting sound waves at different frequencies. This allows scientists to look at different organisms in the water column. Different types of organisms reflect different amounts of energy at different frequencies. The amount of acoustic energy reflected by an individual animal is called the target strength, and is related to the size and anatomy of the species. For example, a fish with a swimbladder (like pollock) reflects more energy than a fish without a swimbladder because its properties are very different from the surrounding water. Some ocean dwelling organisms don’t have swim bladders. Flatfish stay on the bottom so they don’t need the buoyancy. Floating organisms like jellyfish don’t have them. These organisms will look differently than pollock on an echogram because they have a smaller target strength.
Transducers convert mechanical waves (sound waves) into an electrical signal and vice versa (like both a loudspeaker and a microphone combined). They contain piezoelectric materials sensitive to electricity and pressure: if a voltage is applied to them, they make a pressure or sound wave (transmit), and when a sound wave passes over them, it produces a voltage (receive). When a sound wave (echo from a fish) is received, electoral signal is sent to a computer, which displays the signals as pixels of varying colors as the ship moves along (depth changes up and down on the left of the image, and time and location changes along the bottom of the image). This datum is used to estimate the number and type of fish in the water column, and to determine where the ship should fish next.
The size and colors on the images (called echograms) represent the backscatter at different depths and is related to the density of fish and their target strength. But, since they are dots on a screen, specific identification is not possible. The scientists assume certain strong signals are pollock based on the information they have but, those dots could be other fish. To determine what kind of fish are in the water column at this location, how many are there, and how big they are, other data must be obtained. Biological Trawl Data provides that additional information. More about that in my next blog post……I bet you can’t wait!
The Calm Before the Storm:
So far my trip has been smooth sailing, literally. As NOAA Ship Oscar Dyson sails across the Bering Sea there is a bit of rocking the ship experiences at all times. This is easy enough for one to get used to and sometimes it even becomes comforting, like being rocked to sleep as a child. You adjust to the motion. Over the past couple of days I have been hearing talk of a storm coming our way. On a ship, there are many preparations that occur in order to get ready for a storm. Many items are always secured, such as shelves that have a wall in front so that things don’t fall off. There are “handle bars” in showers and next to toilets (think about that). Along hallways and stairways there are handrails on each side. Mini refrigerators in staterooms are bolted to walls. In fact most things are bolted to walls or stored in containers that are bolted to the wall. In the mess hall (dining room) condiments on tables are in a box so they can’t slide off.
Why do you think this coffee mug is shaped like this (wider at the bottom than the top)?
Ans. The wider bottom of the mug above prevents it from sliding as the ship rocks.
Our bulletin board reminds us to secure for bad weather. This morning, I put small items in drawers, stowed books on shelves and packed my equipment (phone, laptop, camera, chargers and small items in a backpack that can be safely secured in my locker (the “closet” in my stateroom).
In talking to my shipmates with at sea experience, I am getting lots of helpful hints about storm preparations and strategies to use during the storm. Here are some of those suggestions:
*always hold on to railings with both hands when walking or going up steps. At all other times, remember to keep one hand for you (to do whatever you are doing) and one hand for the ship (to hold on).
*keep something in your stomach at all times, even if you are not feeling well
*drink lots of water
*when sleeping in your bunk, place pillows between you and the edge so as not to roll off (I will definitely follow this one, as I am on the top bunk) It also depends upon which direction the ship is rolling. Pillows may need to be put between your head and the wall to prevent head bumps
*go to the lower parts of the ship because the top part will sway more with the waves
I also have been wearing patches to prevent seasickness. Hopefully they will continue to help. Only time will tell how we weather the storm (pun intended). Let’s hope it moves through quickly.
My last few days at sea were rather exciting. Wednesday, I got to attend some medical training necessary at sea in the morning, and then in the afternoon we practiced safety drills. The whole crew ran through what to do in the case of three different ship emergencies: Fire, Abandon Ship and Man Overboard. These drills were pretty life-like, they had a fog machine which they use to simulate smoke for the fire drill. Once the alarm was triggered people gather in their assigned areas; roll was taken, firemen and women suited up and headed to the location where smoke was detected, and from there teams are sent out to assess damage or spreading of the fire, while medical personnel stood prepared for any assistance needed. The abandon ship drill required all men and women on board to acquire their life preserver and full immersion suit, and head to their lifeboat loading locations. Roll is then taken and an appointed recorder jots down the last location of the ship. Once this is done, men and women would have deployed the life rafts and boarded (luckily we did not have to). And for the man overboard drill they threw their beloved mannequin Oscar overboard in a life vest and had everyone aboard practice getting in their look out positions. Once Oscar was spotted, they turned the ship around, deployed an emergency boat and had a rescue swimmer retrieve him.
These drills are necessary so that everyone on board knows what to do in these situations. While no one hopes these emergencies will happen, knowing what to do is incredibly important for everyone’s safety.
Thursday was maybe my favorite day on board. Due to the fact that there are a handful of new personnel on board, practice launching and recovering the survey launch boats was necessary. There are 4 launch boats on top of NOAA Ship Fairweather, each equipped with their own sonar equipment. These boats sit in cradles and can be lowered and raised from the sea using davits (recall the video from the “Safety First blog a few days ago). These four boats can be deployed in an area to allow for faster mapping of a region and to allow for shallower areas to be mapped, which the NOAA Ship Fairweather may not be able to access. Since this is a big operation, and one which is done frequently, practice is needed so everyone can do this safely and efficiently.
Launch boat on a davit
Davit lowering a launch boat
Ali Johnson inside one of the launch boats
With the aid of Ali Johnson as my line coach, I got to help launch and recover two of the survey launch boats from the davits on the top of the ship into the Bering Sea. This is an important job for all personnel to learn, as it is a key part of most survey missions. Learning line handling helps to make sure the survey launches are securely held close to the ship to prevent damage and to safely allow people on and off the launch boats as they are placed in the sea. From learning how to handle the bow and aft lines, to releasing and attaching the davit hooks, and throwing lines from the launches to the ship (which I do poorly with my left hand), all is done in a specific manner. While the practice was done for the new staff on board, it was fun to be involved for the day and I got to see the beauty of the NOAA Ship Fairweather from the Bering Sea.
And I truly enjoyed being on the small launch boats. I then understood what many of the officers mentioned when they told me they enjoyed the small boat work. It’s just fun!
Me on a launch boat, taken by AB Colin Hogan
NOAA Ship Fairweather from a launch
My trip ended in Nome, Alaska, which was in and of itself an experience. Students, you will see pictures later. I am extremely thankful for the crew on board NOAA Ship Fairweather, they are a wonderful mix of passionate, fun professionals. I learned so much!
Being a Teacher at Sea is a strange, yet wonderful experience. Being a teacher, I normally spend the vast majority of my day at work being in charge of my classroom and beautiful students; leading lesson and activities, checking-in with those who need extra help and setting up/tearing down labs all day, as well as hopefully getting some papers graded. However during this experience, I was the student, learning from others about their expertise, experience and passions, as well as their challenges; being in charge of nothing. And given that I had no prior knowledge of hydrography, other than its definition, I was increasingly impressed with the level of knowledge and enthusiasm those on board had for this type of work. It drove my interest and desire to learn all I could from the crew. In fact, I often thought those on board were older than they were, as they are wiser beyond their years in many area of science, technology, maritime studies, NOAA Ship Fairweather specifics and Alaskan wildlife.
NOAA offers teachers the opportunities to take part in different research done by their ships throughout the research season as a Teacher at Sea. The 3 main types of cruises offered to teachers include (taken from the NOAA Teacher at Sea website):
Fisheries research cruises perform biological and physical surveys to ensure sustainable fisheries and healthy marine habitats.
Oceanographic research cruises perform physical science studies to increase our understanding of the world’s oceans and climate.
Hydrographic survey cruises scan the coastal sea floor to locate submerged obstructions and navigational hazards for the creation and update of the nation’s nautical charts.
I was excited to be placed on a Hydrographic Survey boat, as this is an area in my curriculum I can develop with my students, and one which I think they are going to enjoy learning about!
While I was sad to leave, and half way through had a “I wish I would have known about this type of work when I was first looking at jobs” moment (which I realize was not the goal of this fellowship or of my schools for sending me), I am super excited to both teach my students about this important work and also be a representative of this awesome opportunity for teachers. I will wear my NOAA Teacher at Sea swag with pride!
From New Hampshire and coming soon this August from the Arctic
Yesterday, June 21, 2018, was the last day of school for us at the Maple Street School in Hopkinton, New Hampshire. It was an appropriate day for the last day of school as summer vacation starts on the summer solstice this year. We ended the school year with a promotion of the NOAA research mission I will be taking part in this summer. Part of this unique learning opportunity is to bring the learning experience to students and the general public, not only in Hopkinton, NH but across the country. If you have found my blog, congratulations! Please follow the blog so you to can join me on this adventure.
Overview of Mission
There will be over 40 scientists and I the Science teacher headed into the Arctic Ocean sailing out of Nome Alaska to the Barrow Canyon. The Barrow Canyon is an underwater gorge that runs East to North West of Barrow Alaska and is known for its rich marine life. Scientists will be conducting numerous studies and observations at many locations during the trip. The scientific studies taking place will have a common theme, how are the rapid changing Arctic Sea Ice conditions affecting the region?
For the last two years, regional sea ice in the Bering Sea has been at a historic low. What changes does this have on the region’s ecosystem? This includes the microscopic plankton to fish, marine birds to larger marine mammals. These creatures live anywhere from the sea floor to the air, and all these areas will be observed. As we observed in my 6th-grade science class this year, in an ecosystem the living (biotic) is affected by the non-living (or abiotic). Non-living factors that will be measured will include the salinity of the water, the water temperature, and changes in ocean currents themselves. Changes in ocean currents have larger effects on local and regional climates, which include those on land.
This annual survey will allow for changes over time to monitored. What will scientists learn this year? Follow this blog to find out. To sign up to be notified of updates click the follow button on the bottom right of your screen and you will be notified when there is a new post to read. The blog will be updated at the start of and during the mission from the from one of the most remote areas of the world, north of the Arctic Circle in the Arctic Ocean. I look forward to talking to you again soon from the Arctic Ocean during the first week of August!
I must begin by trying to convey how honored and excited I am to be a part of NOAA’s Teacher At Sea program. I will be sailing aboard NOAA Ship Oscar Dyson with another teacher, Lee Teevan. What an adventure! More importantly, it’s an opportunity to gain knowledge about the management of the Bering Sea Fishery, the commercial fishing industry and how these forces impact both the ocean ecosystem and our lives. It is an opportunity to educate my students and community about these factors and the career opportunities that support them. It also demonstrates the fact that, life long learning opportunities come in many forms.
For the last five years I have been teaching at Lanphier High School in Springfield, Illinois. I look forward to bringing lessons into the classroom that can spark an interest in an unfamiliar aspect of scientific research and its real-life implications. Through these lessons, I also hope to expand student awareness of the related realm of job opportunities associated with this work.
I graduated with a Bachelor’s degree in Biology and a concentration in Fishery Science. I earned my Teacher Certification in Biology and the Sciences. Following graduation, I chose a career in teaching. Through my education at the University of Wisconsin – Superior, I became interested in the Foreign Fishery Observer Program. I was a Foreign Fishery Observer on Japanese fishing ships that fished primarily for Arrowtooth Flounder in the Bering Sea. This involved sampling the catches, and determining how much of each species of fish were caught to guard against exceeding their assigned quota. I spent a month and a half aboard 3 different ships. The opportunity to work on NOAA Ship Oscar Dyson will allow me to learn about the Fisheries Management aspect of the Bering Sea.
I returned to school to earn my Special Education Teaching Certification and earned a Master’s Degree in Educational Administration. As a teacher, I continued going to school and learning about many topics that supported my work. In order to increase my knowledge about Fishery Science, I took a class in which I created a teacher’s manual (An Aquatic Organisms Educational Module for the Therkildsen Field Station at the Emiquon Wetland Area on the Illinois River). This manual allows teachers to bring students to the field station, collect plankton samples and use the labs to study the results of their sampling. Students learn about the many aspects of the wetland ecosystem and even calculate estimates of the planktonic biomass of the wetland. How fun is that!
I hope with my introduction, I peak your interest in this aspect of our world. I invite you to be a part of my experience in order to continue your life long learning journey as I continue mine.
NOAA Teacher at Sea Vincent Colombo Aboard NOAA Ship Oscar Dyson June 11 – 30, 2015
Mission: Annual Walleye Pollock Survey Geographical area of the cruise: The Gulf of Alaska Date: June 21, 2015
Weather Data from the Bridge:
Wind Speed: 6.02 knots
Sea Temperature: 9.99 degrees Celsius
Air Temperature: 9.06 degrees Celsius
Air Pressure: 1016.59 mb
Science and Technology Log:
You are sleeping soundly in your bed. Awakening you is your phone ringing… it’s 5:30 am… that could only mean one thing, it’s the school calling to say school is delayed 2 hours… FOG. No, it’s not the kind of fog depicted in John Carpenter’s thriller; it’s the kind that the local weatherman says is a localized phenomenon that reduces visibility to less than a quarter mile. If you live on Delmarva, you have experienced this sort of fog and know that it can turn a normal commute into a complicated one.
Here in the Alaskan summer, especially the Aleutian Chain, Gulf of Alaska, and the Bering Sea, fog is a normal, and potentially ALL day event. The only constant on this research cruise so far has been waking up every day and watching our NOAA Corps Officers navigate through a very dense fog.
But what causes fog, and why is it so prevalent here?
Fog is most simply described as a cloud on the ground. It is made up of condensed water droplets that have encircled some sort of condensation nuclei (something water can attach to). On the open sea, that condensation nuclei is salt, which has upwelled (brought to the surface) from turbulent seas or breaking waves. That translates to the rougher the seas, the more chance there is for condensation nuclei, and thus fog.
Fog is able to be formed when the air temperature is cooler than the dew point. The dew point refers to the specific temperature which water can condense. Dew point varies with humidity and temperature, you can calculate dew point here.
Because the sun exposure is so long here in the Alaskan summer day, there is ample time for the sun’s radiant energy to heat up the upper layer of the ocean causing evaporation. The now warmer air, filled with water vapor, meets the cool waters of the Northern Pacific or Bering Sea, and bam, here comes a fog bank. The most common name for this type of fog is Sea Fog, scientifically called Advection fog. The combination of salt is especially important because salt is a unique condensation nuclei in that it will allow fog to form when the humidity is as low as 70%. It can also turn from a gentle fog to a dense fog in little to no time. Air movement, or wind can actually cause more fog, rather than the contrary belief it will just blow away.
So what have I learned? NOAA Ship Oscar Dyson has a very loud fog horn which the NOAA Corps Officers sound on a regular basis during these conditions.
Here is what you need to know if you are ever on the ocean in a fog bank!
One prolonged sounding of the horn – this means “Hey! I am here and moving, don’t hit me!”
Two prolonged soundings of the horn – this means “Hey! I am a big boat, but not moving, don’t hit me!”
One prolonged sounding of the horn followed by two short blasts – “Hey! I am a big boat and am either towing something (like a fishing net) or lowered in my ability to maneuver. Stay away and make room!”
One prolonged sounding of the horn followed by three short blasts – “Hey! I am a big boat that is being towed. Stay away from me because I have no power!”
One short blast of the horn, followed by a prolonged sounding, then one short blast; or rapidly ringing of a bell for five seconds every minute – “Hey I am anchored over here, you can’t see me, stay away.”
The life at sea is quite interesting. Luckily we have every luxury of home on board the Oscar Dyson, to include internet (sometimes), hot showers, and a nice bed. I have also been introduced to the game of Cribbage, an apparent maritime tradition. I cannot say that I fully understand it, but there are bunches of ways the number 15 can be made.
Fishing is life up here, and every day I can expect at least one or two trawls (pulling of a net behind the ship). I was introduced to what is called a Methot net, which is used for catching smaller organisms. I was able to look at Krill for the first time in my life the other day, a keystone organism for a lot of the Alaskan food web.
Also very cool was seeing the MACE scientists use a cool underwater camera. Ever wonder what is under 300 meters of water? With this camera that can be deployed in less than 5 minutes, scientists can get a picture of the sea floor on a live feed.
Meet the Crew:
Richardo Guevara. Richardo has been with NOAA for 7 years and is the Ship’s Electronics Technician. What does this mean? Richardo works on various systems on the ship that involve communications, such as radios, acoustics, data sensors, radar, telephones, televisions, navigation, and computer systems. Richardo is the IT guru and knows everything about the ship’s day to day mission with technology. Richardo works for NOAA because he enjoys the life at sea, its benefits, and the satisfaction of working side by side with scientists.
Richardo is a 23 year veteran of the United States Air Force. During his service he gained a plethora of knowledge suited towards his current position on board the Oscar Dyson. Richardo was born and raised in Pensacola, Florida, but now resides on the Oregon coast. Richardo says that this job requires a lot of flexibility, and his time in the military gave him this valuable life skill. According to Richardo: “A lot of times people seem to get the notion that you must have college to succeed, but I do not have a college degree. I cannot understate how important it is to get your high school diploma and to value that. Then it is up to you to go your own way and have success.”
Meet the crew:
Kirk Perry. Kirk is the lead fisherman aboard the Oscar Dyson and is acting Chief Boatswain for our research cruise. Kirk has been with NOAA since 2004, and is in charge of any activity which takes place on deck. His job includes, but is not limited to, using fishing equipment, deploying science equipment, anchoring, net maintenance, standing lookout on the bridge, being a helmsman, managing a deck crew of 6, and operating a crane. Kirk joined NOAA for the adventure of a lifetime, to fish in Alaska. He never intended to stay this long but absolutely loves his job and he says working with scientists is very rewarding.
Out of curiosity in the neighborhood, Kirk discovered the world of fishing and hunting from a Czechoslovakian neighbor in San Jose, California. Kirk started commercially fishing at age 10 in Monterey Bay, California and has not looked back since. He graduated from Cal Poly SLO with a degree in Natural Resources Management while on scholarship for college baseball. Kirk loves baseball and football and is a diehard San Francisco Giants and 49ers fan. He also isn’t too bad on the guitar either.
Kirk was my unofficial, but official Alaskan fishing guide. It was his handy work that set me up with rigs and a tackle for my Halibut at the beginning of my trip. Kirk and I have a lot in common and have had countless discussions about the outdoors. A fun fact about Kirk, he can identify any bird that flies by the ship, whether it’s out of necessity or because he has been hunting so long.
Before we get into detail about data and where all of it ends up, let’s talk acronyms. This trip has been a lot like working in the Special Education world with what we like to call “Alphabet Soup.” We use acronyms a lot and so does the NOAA Science world. Here are a few important acronyms…
AFSC – Alaska Fisheries Science Center (located in Seattle, WA)
MACE – Midwater Assessment and Conservation Engineering Program (also in Seattle)
CLAMS – Catch Logger for Acoustic Midwater Surveys
We recorded data in a program called CLAMS as we processed each haul. The CLAMS (see above: Catch Logger for Acoustic Midwater Surveys) software was written by two NOAA Scientists. Data can be entered for length, weight, sex and development stage. It also assigns a specimen number to each otolith vial so the otoliths can be traced back to a specific fish. This is the CLAMS screen from my very first haul on the Oscar Dyson.
From the Species List in the top left corner you can see I was measuring the length of Walleye Pollock- Adult. In that particular haul we also had Age 2 Pollock, a Chum Salmon and Chrysaora melanaster (a jellyfish or two). There is the graph in the lower left corner that plots the sizes in a bar graph and the summary tells me how many fish I measured – 462! When we finish in the Wet Lab we all exit out of CLAMS and Robert, a zooplankton ecologist working on our cruise, ducks into the Chem Lab to export our data. There were a total of 142 hauls processed during the 2014 Summer Walleye Pollock Survey (June 12 – August 13) so this process has happened 142 times in the last two months!
Next, it is time to export the data we collected onto a server known as MACEBASE. MACEBASE is the server that stores all the data collected on a Pollock survey. Not only will the data I helped collect live in infamy on MACEBASE, all the data collected over the last several years lives there, too. CLAMS data isn’t the only piece of data stored on MACEBASE. Information from the echosounding system, and SBE (Sea-bird Electronics temperature depth recorder) are uploaded as well.
We’ve reached the end of the summer survey. Now what? 142 hauls, two months of echosounder recordings, four Drop TS deployments and 57 CTD’s. There have also been 2660 sets of otoliths collected. Scientists who work for the MACE program will analyze all of this information and a biomass will be determined. What is a biomass? Some may think of it as biological material derived from living or recently living organisms. In this case, biomass refers to the total population of Walleye Pollock in the Bering Sea. In a few weeks our Chief Scientist Taina Honkalehto will present the findings of the survey to the Bering Sea Plan Team.
That team reviews the 2014 NOAA Fisheries survey results and Pollock fishing industry information and makes science-based recommendations to the North Pacific Fishery Management Council, who ultimately decide on Walleye Pollock quotas for 2015. Think about Ohio’s deer hunting season for a minute. Each hunter is given a limit on how many deer they can tag each year. In Pickaway & Ross counties we are limited to three deer – two either sex permits and one antlerless permit. If every deer hunter in Ohio was allowed to kill as many deer as they pleased the deer population could be depleted beyond recovery. The same goes for Pollock in the Bering Sea. Commercial fisheries are given quotas and that is the maximum amount of Pollock they are allowed to catch during a given year. The scientific research we are conducting helps ensure the Pollock population remains strong and healthy for years to come.
Earlier today I took a trip down to the Engine Room. I can’t believe I waited until we were almost back to Dutch Harbor to check out this part of the ship. The Oscar Dyson is pretty much a floating city! Put on some ear protection…it’s about to get loud!
Why must we wear ear protection? That large machine behind me! It is a 3512 Caterpillar diesel engine. The diesel engine powers an electric generator. The electric generator gives power to an electric motor which turns the shaft. There are four engine/generator set ups and one shaft on the Dyson. The shaft turns resulting in the propeller turning, thus making us move! When we are cruising along slowly we can get by with using one engine/generator to turn the shaft. Most of the time we are speeding along at 12 knots, which requires us to use multiple engines/generators to get the shaft going. Here is a shot of the shaft.
The EOS, or Engineering Operation Station, is the fifth location where the ship can be controlled. The other four locations are on the Bridge.
This screen provides Engineers with important info about the generators (four on board) and how hard they’re working. At the time of my tour the ship was running on two generators (#1 and #2) as shown on the right side of the screen. #3 and #4 were secured, or taking a break. The Officer of the Deck, who is on the Bridge, can also see this screen. You can see an Ordered Shaft RPM (revolutions per minute) and an Actual Shaft RPM boxes. The Ordered Shaft RPM is changed by the Officer on Deck depending on the situation. During normal underway conditions the shaft is running at 100-110 RPMs. During fishing operations the shaft is between 30 and 65 RPMs.
When I talked about the trawling process I mentioned that the Chief Boatswain is able to extend the opening of the net really far behind the stern (back) of the ship. This is the port side winch that is reeled out during trawling operations. There are around 4300 meters of cable on that reel! How many feet is that?
When Lt. Ostapenko and ENS Gilman were teaching me how to steer this ship they emphasized how sensitive the steering wheel is. Only a little fingertip push to the left can really make a huge difference in the ship’s course. This is the hydraulic system that controls the rudder, which steers the ship left or right. The actual rudder is hidden down below, under water. I’m told it is a large metal plate that stands twice as tall as me. This tour really opened my eyes to a whole city that operates below the deck I’ve been working on for the last 18 days. Without all of these pieces of equipment long missions would not be possible. Because the Oscar Dyson is well-equipped it is able to sail up to forty days at a time. What keeps it from sailing longer voyages? Food supply!
And just like that I remembered all good things must come to an end. This is the end of the road for the Summer Walleye Pollock Survey and my time with the Oscar Dyson. We have cleaned and packed the science areas of the ship. Next we’ll be packing our bags and cleaning our staterooms. In a matter of hours we’ll be docking and saying our goodbyes. There have been many times over the last 19 days where I’ve stood, staring out the windows of the Bridge and thinking about how lucky I am. I will never be able to express how thankful I am for this opportunity and how it will impact my life for many, many years. A huge THANK YOU goes to the staff of NOAA Teacher at Sea. My fellow shipmates have been beyond welcoming and patient with me. Thank you, thank you, THANK YOU to everyone on board the Dyson!! I wish you safe travels and happy fishing!
To Team Bluefin Tuna (night shift Science Crew), thank you for your guidance, ice cream eating habits, card game instruction, movie watching enthusiasm, many laughs and the phrase “It is time.” Thanks for the memories! I owe y’all big time!
Did you know? The ship also has a sewage treatment facility and water evaporation system onboard. The MSD is a septic tank/water treatment machine and the water evaporation system distills seawater into fresh potable (drinking and cooking) water.
Last night and afternoon was by far the craziest we’ve seen on the Oscar Dyson. The winds were up to 35 knots (about 40 miles an hour). The waves were averaging 12 feet in height, and sometimes reaching 15-18 feet in height. Right now I’m sitting on the bridge and waves are around 8 feet. With every rise the horizon disappears and I’m looking up at stark grey clouds. With every drop the window fills with views of the sea, with the horizon appearing just below the top of the window frames.
Ensign Gilman, a member of NOAA Corps, explains to me how the same thing that makes the Bering Sea good for fish makes things rough for fishermen.
“This part of the Bering Sea is shallow compared to the open ocean. That makes the water easier for the wind to pick up and create waves. When strong winds come off Russia and Alaska, it kicks up a lot of wave action,” Ensign Gilman says.
“It’s not so much about the swells (wave height),” he continues. “It’s about the steepness of the wave, and how much time you have to recover from the last wave.” He starts counting between the waves… “one… two… three… three seconds between wave heights… that’s a pretty high frequency. With no time to recover, the ship can get rocked around pretty rough.”
Rough is right! Last night I got shook around like the last jelly bean in the jar. I seriously considered finding some rope to tie myself into my bunk. There were moments when it seemed an angry giraffe was jumping on my bunk. I may or may not have shouted angrily at Sir Isaac Newton that night.
Which brings us to Sea Sickness.
Lt. Paul Hoffman, a Physician’s Assistant with the U.S. Public Health Service, explains how sea sickness works.
“The inner ears are made up of tubes that allow us to sense motion in three ways,” Hoffman explains. “Forward/back, left/right, and up/down. While that’s the main way our brain tells us where we are, we use other senses as well.” He goes on to explain that every point of contact… feet and hands, especially, tell the brain more information about where we are in the world.
“But another, very important piece, are your eyes. Your eyes are a way to confirm where you are in the world. Sea Sickness tends to happen when your ears are experiencing motion that your eyes can’t confirm,” Hoffman says.
For example, when you’re getting bounced around in your cabin (room), but nothing around you APPEARS to be moving (walls, chair, desk, etc) your brain, essentially, freaks out. It’s not connected to anything rational. It’s not enough to say “Duhh, brain, I’m on a boat. Of course this happens.” It happens in a part of the brain that’s not controlled by conscious thought. You can’t, as far as I can tell, think your way out of it.
Hoffman goes on to explain a very simple solution: Go look at the sea.
“When you get out on deck, the motion of the boat doesn’t stop, but your eyes can look at the horizon… they can confirm what your ears have been trying to tell you… that you really are going up and down. And while it won’t stop the boat from bouncing you around, your stomach will probably feel a lot better,” Hoffman says.
And he’s right. Being up on the bridge… watching the Oscar Dyson plow into those stout waves… my brain has settled into things. The world is back to normal. Well, as normal as things can get on a ship more than a third of the way around the world, that is.
Let’s meet a few of the good folks on the Oscar Dyson.
NOAA Crew Member Alyssa Pourmonir
Job Title: Survey Technician
Responsibilities on the Dyson: “I’m a liaison between crew and scientists, work with scientists in the wet lab, put sensors onto the trawling nets, focus on safety, maintaining all scientific data and equipment on board.” A liaison is someone who connects two people or groups of people.
Education Level Required: “A Bachelors degree in the sciences.” Alyssa has a BS in Marine and Environmental Science from SUNY Maritime with minors in oceanography and meteorology.
Job or career you’ve had before this: “I was a life guard/swim instructor in high school, then I was in the Coast Guard for three years. Life guarding is the BEST job in high school!”
Goal: “I strive to bring about positive change in the world through science.”
Weirdest thing you ever took out of the Sea: “Lump Sucker: They have big flappy eyebrows… they kinda look like a bowling ball.”
Dirtiest job you’ve ever had to do on a ship: “Sexing the fish (by cutting them open and looking at the fish’s gonads… sometimes they explode!) is pretty gross, but cleaning the PCO2 filter is nasty. There are these marine organisms that get in there and cling to the filter and you have to push them off with your hands… they get all slimy!”
NOAA Rotating Technician Ricardo Guevara
Job Title: Electronics Technician
Responsibilities on the Dyson: “I maintain and upkeep most of the low voltage electronics on the ship, like computer networking, radio, television systems, sensors, navigation systems. All the equipment that can “talk,” that can communicate with other devices, I take care of that.”
Education level Required: High school diploma and experience. “I have a high school diploma and some college. The majority of my knowledge comes from experience… 23 years in the military.”
Job or career you’ve had before this: “I was a telecommunications specialist with the United States Air Force… I managed encryption systems and associated keymat for secure communications.” This means he worked with secret codes.
Trickiest problem you’ve solved for NOAA: “There was a science station way out on the outer edge of the Hawaiian Islands that was running their internet off of dial-up via satellite phone when the whole thing shut down on them… ‘Blue Screen of Death’ style. We couldn’t just swap out the computer because of all the sensitive information on it. I figured out how to repair the disk without tearing the machine apart. Folks were extremely happy with the result… it was very important to the scientists’ work.”
What are you working on now? “I’m migrating most of the ship’s computers from windows xp to Windows 7. I’m also troubleshooting the DirecTV system. The problem with DirecTV is that the Multi-Switch for the receivers isn’t communicating directly with the satellite. Our antenna sees the satellite, but the satellite cannot ‘shake hands’ with our receiver system.” And that means no Red Sox games on TV! Having entertainment available for the crew is important when you’re out to sea for two to three weeks at a time!
What’s a challenging part of your job on the Dyson? “I don’t like it, but I do it when I have to… sometimes in this job you have to work pretty high up. Sometimes I have to climb the ship’s mast for antenna and wind sensor maintenance. It’s windy up there… and eagles aren’t afraid of you up there. That’s their place!”
Lt. Paul Hoffman
Job Title: Physician Assistant (or P.A.) with the U.S. Public Health Service
Responsibilities on the Dyson: He’s effectively the ship’s doctor. “Whenever a NOAA ship travels outside 200 miles of the U.S. coast, they need to be able to provide an increased level of medical care. That’s what I do,” says Hoffman.
Education required for this career: “Usually a Masters degree from a Physician’s Assistant school with certification.”
Job or career you’ve had before this: “Ten and a half years in the U.S. Army, I started off as an EMT. Then I went on to LPN (Licensed Practical Nurse) school, and then blessed with a chance to go on to PA school. I served in Iraq in 2007-2008, then returned for 2010-2011.”
Most satisfying thing you’ve seen or done in your career: “Knowing that you personally had an impact on somebody’s life… keeping somebody alive. We stabilized one of our soldiers and then had a helicopter evac (evacuation) under adverse situations. Situations like that are what make being a PA worthwhile.”
Could you explain what the Public Health Service is for folks that might not be familiar with it?
“The Public Health Service is one of the seven branches of the U.S. Military. It’s a non-weaponized, non-combative, all-officer corps that falls under the Department of Health and Human Services. We’re entirely medical related. Primary deployments (when they get sent into action) are related to national emergency situations… hurricanes, earth quakes… anywhere where state and local resources are overrun… they can request additional resources… that’s where we step in. Hurricane Katrina, the Earthquake in Haiti… a lot of officers saw deployment there. Personally, I’ve been employed in Indian Health Services in California and NOAA’s Aircraft Operations Center (AOC)… they’re the hurricane hunters,” Hoffman concludes.
Kids, when you’ve been around Lt. Hoffman for a while, you realize “adverse conditions” to him are a little tougher than a traffic jam or missing a homework assignment. I’ve decided to call him, and the rest of the Public Health Service, “The Batman of Health Care.” When somebody lights up the Bat Signal, they’re there to help people feel better.
Date: August 8, 2014 Weather information from the Bridge:
Air Temperature: 11° C
Wind Speed: 27 knots
Wind Direction: 30°
Weather Conditions: High winds and high seas
Latitude: 60° 35.97 N
Longitude: 178° 56.08 W Science and Technology Log:
If you recall from my last post we left off with fish on the table ready to be sorted and processed. Before we go into the Wet Lab/Fish Lab we need to get geared up. Go ahead and put on your boots, bibs, gloves and a jacket if you’re cold. You should look like this when you’re ready for work…
The first order of business is sorting the catch. We don’t have a magic net that only catches Pollock. Sometimes we pick up other treats along the way. Some of the cool things we’ve brought in are crabs, squid, many types of jellyfish and the occasional salmon. One person stands on each side of the conveyor belt and picks these other species out so they aren’t weighed in with our Pollock catch. It is very important that we only weigh Pollock as we sort so our data are valid. After all the Pollock have been weighed, we then weigh the other items from the haul. Here are some shots from the conveyor belt.
Not every single fish in our net is put into the sorting bin. Only random selection from the catch goes to the sorting bin. The remaining fish from the haul are returned back to the sea. Those fish who find themselves in the sorting bin are cut open to determine their sex. You can’t tell the sex of the fish just by looking at the outside. You have to cut them open, slide the liver to the side and look for the reproductive organs. Males have a rope-like strand as testes. Females have ovaries, which are sacs similar to the stomach but are a distinctly different color.
Okay, no more slicing open fish. For now! The next step is to measure the length of all the fish we just separated by sex. One of the scientists goes to the blokes side and another goes to the sheilas side. We have a handy-dandy tool used to measure and record the lengths called an Ichthystick. I can’t imagine processing fish without it!
That is the end of the line for those Pollock but we still have a basket waiting for us. A random sample is pulled off the conveyor belt and set to the side for another type of data collection. The Pollock in this special basket will be individually weighed, lengths will be taken and a scientist will determine if it is a male or female. Then we remove the otoliths. What are otoliths? They are small bones inside a fish’s skull that can tell us the age of the fish. Think of a tree and how we can count the rings of a tree to know how old it is. This is the same concept. For this special sample we remove the otoliths, which are labeled and given to a lab on land where a scientist will carefully examine them under a microscope. The scientist will be able to connect the vial containing the otoliths to the other data collected on that fish (length, weight, sex) because each fish in this sample is given a unique specimen number. This is all part of our mission, which is analyzing the health and population of Pollock in the Bering Sea!
At this point we have just about collected all the data we need for this haul. Each time we haul in a catch this process is completed. As of today, our survey has completed 28 hauls. Thank goodness we have a day shift and a night shift to share the responsibility. That would be a lot of fish for one crew to process! For our next topic we’ll take a look at how the data is recorded and what happens after we’ve completed our mission. By the way, “blokes” are males and “sheilas” are females. Now please excuse us while we go wash fish scales off of every surface in the Wet Lab, including ourselves!
Just so you know, we’re not starving out here. In fact, we’re stuffed to the gills – pun completely intended. Our Chief Steward Ava and her assistant Adam whip up some delicious meals. Since I am on night shift I do miss the traditional breakfast served each morning. Sometimes, like today, I am up for lunch. I’m really glad I was or I would have missed out on enchiladas. That would have been a terrible crisis! Most people who know me realize there is never enough Mexican food in my life! Tacos (hard and soft), rice and beans were served along with the enchiladas. Each meal is quite a spread! If I have missed lunch I’ll grab a bowl of cereal to hold me over until supper. I bet you’ll never guess we eat a lot of seafood on board. There is usually a fish dish at supper. We even had crab legs one night and fried shrimp another. Some other supper dishes include pork chops, BBQ ribs, baked steak, turkey, rice, mashed potatoes, and macaroni and cheese plus there are always a couple vegetable dishes to choose from. We can’t forget about dessert, either. Cookies, cakes, brownies or pies are served at nearly every meal. It didn’t take long for me to find the ice cream cooler, either. What else would one eat at midnight?!
Ava and Adam are always open to suggestions as well. Someone told Ava the night shift Science Crew was really missing breakfast foods so a few days ago we had breakfast for supper. Not only did they make a traditional supper meal, they made a complete breakfast meal, too! We had pancakes, waffles, bacon, eggs, and hashbrowns. It was so thoughtful of them to do that for us, especially on top of making a full meal for the rest of the crew. Thanks Ava and Adam!
There are situations where a crew member might not be able to make it to the Mess during our set serving schedule. Deck Crew could be putting a net in or taking it out or Science Crew could be processing a catch. We never have to worry, though. Another great thing about Ava and Adam is they will make you a plate, wrap it up and put it in the fridge so you have a meal for later.
Like I said, we’re not going hungry any time soon! Here are some shots from the Mess Deck (dining room).
Did you know?
Not only are otoliths useful to scientists during stock assessment, they help the fish with balance, movement and hearing.
Science and Technology Log: Abiotic Factors in the Bering Sea
Ecosystems are made up of biotic and abiotic factors. Biotic is just another word for “stuff that is, or was, alive.” In a forest, that would include everything from Owl to Oak Tree, from bear to bacteria, and from fish to fungi. It includes anything alive, or, for that matter, dead. Keep in mind that “dead” is not the same as “non-living.”
“Non-living” describes things that are not, cannot, and never will be “alive.” These things are referred to as “abiotic.” (The prefix a- basically means the same as non-). Rocks, water, wind, sunlight and temperature are all considered abiotic factors. And while the most obvious threat to a salmon swimming up river might be the slash of a bear’s mighty claw, warm water could be even more deadly. Warm water carries less dissolved oxygen for the fish to absorb through their gills. This means that a power plant or factory that releases warm water into a river could actually cause fish to suffocate and, well, drown.
Fish in the Bering Sea have the same kind of challenges. Like Goldilocks, Pollock are always looking for sea water that is just right. The Oscar Dyson has the tools for testing all sorts of Abiotic factors. This is the Conductivity Temperature Depth sensor (Also known as the CTD).
The CTD sends signals up to computers in the cave to explain all sorts of abiotic conditions in the water column. It can measure how salty the water is by testing how well the water conducts electricity. It can tell you how cloudy, or turbid, the water is with a turbidity sensor. It can even tell you things like the amount of oxygen dissolved in the ocean.
To see how abiotic factors drive biotic factors, take a look at this.
I know, you may want to turn the graph above on its side… but don’t. You’ll notice that depth is on the y-axis (left). That means that the further down you are on the graph, the deeper in the sea you are. The blue line represents the water temperature at that depth. Where do you see the temperature drop?
Right… The temperature drops rapidly between about 20 and 35 meters. This part of the water column is called the Thermocline, and you’ll find it in much of the world’s oceans. It’s essentially where the temperature between surface waters (which are heated by the sun) and the deeper waters (typically dark and cold) mix together.
OK, so you’re like “great. So what? Water gets colder. Big deal… let’s throw a parade for science.”
Well, look at the graph to the right. It was made from another kind of data recorded by the CTD.
The green line represents the amount of fluorescence. Fluorescence is a marker of phytoplankton. Phytoplankton are plant-like protists… the great producers of the sea! The more fluorescence, the more phytoplankton you have. Phytoplankton love to live right at the bottom of the thermocline. It gives them the best of both worlds: sunlight from above and nutrients from the bottom of the sea, which so many animals call home.
Now, if you’re a fish… especially a vegetarian fish, you just said: “Dinner? I’m listening…” But there’s an added bonus.
Look at this:
That orange line represents the amount of oxygen dissolved in the water. How does that compare to the other graphs?
Yup! The phytoplankton is hanging down there at the bottom of the thermocline cranking out oxygen! What a fine place to be a fish! Dinner and plenty of fresh air to breathe! So here, the abiotic (the temperature) drives the biotic (phytoplankton) which then drives the abiotic again (oxygen). This dance between biotic and abiotic plays out throughout earth’s ecosystems.
Another major abiotic factor is the depth of the ocean floor. Deep areas, also known as abyss, or abyssal plains, have food sources that are so far below the surface that phytoplankton can’t take advantage of the ground nutrients. Bad for phytoplankton is, of course, bad for fish. Look at this:
That sloping red line is the profile (side view of the shape of the land) of the ocean floor. Those blue dots on the slope are fish. As Dr. Mikhail Stepanenko, a visiting Pollock specialist from Vladivostok, Russia, puts it, “after this… no more Pollock. It’s too deep.”
He goes on to show me how Pollock in the Bering Sea are only found on the continental shelf between the Aleutian Islands and Northeastern Russia. Young Pollock start their lives down near the Aleutians to the southeast, then migrate Northwest towards Russia, where lots of food is waiting for them.
The purple line drawn in represents the drop-off you saw above… right before the deep zone. Pollock tend to stay in the shallow areas above it… where the eating is good!
Once again, the dance between the abiotic and the biotic create an ecosystem. Over the abyss, Phytoplankton can’t take advantage of nutrients from the deep, and fish can’t take advantage of the phytoplankton. Nonliving aspects have a MASSIVE impact on all the organisms in an ecosystem.
Next time we explore the Biotic side of things… the Sub-arctic food web!
Personal Log: The Order of the Monkey’s Fist.
Sweet William, a retired police officer turned ship’s engineer, tells the story of the order of the monkey’s fist.
The story goes that some island came up with a clever way to catch monkeys. They’d place a piece of fruit in a jar just barely big enough for the fruit to fit through and then leave the jar out for the monkeys. When a monkey saw it, they’d reach their hand in to grab the fruit, but couldn’t pull it out because their hands were too big now that they had the fruit in it. The monkey, so attached to the idea of an “easy” meal wouldn’t let go, making them easy pickings for the islanders. The Monkey’s Fist became a symbol for how clinging to our desires for some things can, in the end, do more harm than good. That sometimes letting go of something we want so badly is, in the end, what can grant us relief.
Another story of the origin of the monkey’s fist goes like this: A sea captain saw a sailor on the beach sharing his meal with a monkey. Without skipping a beat, the monkey went into the jungle and brought the sailor some of HIS meal… a piece of fruit.
Whatever the true origin of the Order is, the message is the same. Generosity beats selfishness at sea. It’s often better to let go of your own interests, sometimes, and think of someone else’s. Onboard the Oscar Dyson, when we see someone committing an act of kindness, we put their name in a box. Every now and then they pull a name from the box, and that person wins something at the ship store… a hat or a t-shirt or what have you. Of course, that’s not the point. The point is that NOAA sailors… scientists, corps, and crew… have each other’s backs. They look out for each other in a place where all they really have IS each other.
Now that we have chosen a location to fish, the real fun begins! With a flurry of action, the Bridge (control center of the ship) announces we are going to trawl (fish). This alerts the Deck Crew who has the responsibility of deploying a net. There are three different types of trawls, AWT (Aleutian Wing Trawl), 83-112 Bottom Trawl, and the Marinovich. The type of trawl chosen depends on the depth in the water column and proximity to the bottom of what we want to catch. The 83-112 Bottom Trawl pretty much does what it is called. It is drug along the bottom of the ocean floor and picks up all sorts of awesome sea creatures. The Marinovich is a smaller net that is trawled near the surface. For this Pollock survey, we have primarily used the AWT. It is a mid-water net and that is the area where Pollock primarily live.
As you can see in the diagram, the AWT is cone-shaped. When fully deployed it is 491 feet long! The opening of the net, similar to a mouth, is about 115 feet wide. The Chief Boatswain (pronounced bo-sun) controls the winches that let wire out which extends the opening of the net at least another 500 feet from the aft (rear) deck of the ship.
The Deck Crew begins to roll out the net and prepares it for deployment. There are several pieces of equipment attached along the way. A Camtrawl is attached first. Can you guess what it does? It is essentially a camera attached to the net that records what is being caught in the net. Near the Camtrawl, a pocket net is attached to the bottom side of the AWT. This pocket net can show scientists what, if any, fish are escaping the AWT. On a piece of net called the kite that is attached to the headrope (top of the mouth/opening), the FS70 and SBE are attached. The FS70 is a transducer that reports data to the Bridge showing the scientist what is coming into the net, similar to a fish finder. The SBE is bathythermograph that records water temperature and depth. Tomweights are added next. These heavy pieces of chain help weigh the footrope (bottom of the mouth/opening) down, pulling it deeper into the water. The net continues to be reeled out and is finally connected to lines on each side of the deck. The horizontal distance between the lines helps the net to fully open its mouth.
While the net is out the Bridge crew, the Chief Boatswain, the Survey Tech and at least one scientist are on the Bridge communicating. Each person has a role to ensure a successful catch. The Bridge crew controls the speed and direction of the boat. The Chief Boatswain controls the net; changing the distance it is deployed. The Survey Tech has information to report on one of the computers. Lastly, the scientist watches multiple screens, making the decision on how far out the net goes and when to haulback (brings the net in). Ultimately, the Bridge crew is the liaison between all of the other departments and has the final decision on each step of the process, keeping everyone’s safety in mind. This piece of the fishing puzzle quickly became my favorite part of the survey. It is so neat to listen to the chatter of all these groups coming together for one purpose.
Once we have reached haulback the Chief Boatswain alerts his deck crew and they begin reeling the net back in. They watch to make sure the lines are going back on the reel evenly. When the tomweights come back on deck they are removed. The next items to arrive are the FS70 and SBE. They are removed and the reeling in continues. The Camtrawl comes in and is removed and the pocket net is checked for fish. By that point we are almost to the end of the net where we’ll find our catch. Because the net is very heavy, the deck crew uses a crane to lift it and move it over the table. A member of the Deck Crew pulls a rope and all the fish are released onto the table. The table is a piece of equipment that holds the fish on the deck but feeds them into the Wet Lab by conveyor belt. Once the fish have been removed from the net it is finally rolled up onto the reel and awaits its next deployment. In my next blog we’ll get fishy as we explore the Wet Lab!
I have delayed writing about this next location on the ship because it is my favorite place and I want to make sure I do it justice. Plus, the Officers who stand watch on the Bridge are really awesome and I don’t want to disappoint them with my lack of understanding. Here are a few pictures showing some of the things I actually do understand…
This screen provides Officers with valuable information about the ship’s engine, among other things. This diagram shows multiple tanks located on the ship. Some tanks take in seawater as we use diesel fuel, drinking water, etc. to counter balance that usage and keep the Dyson in a state of equilibrium. Also, if they are expecting high seas they may take in some of the seawater to make our ship heavier, reducing the effects of the waves on the ship. I’ve been told this may be important in a couple of days because we’re expecting some “weather.” That makes me a little nervous!
The General Alarm is really important to the safety of all those on the ship but it is not my favorite thing every day at noon. The General Alarm is used to signal us in an emergency – Abandon Ship, Man Overboard, Fire, etc. It is tested every day at noon…while I’m sleeping!! “Attention on the Dyson, this is a test of the ship’s General Alarm.” BEEEP. “That concludes the test of the ship’s General Alarm. Please heed all further alarms.”
What would happen if all of our fancy technology failed on us? How would we know where to tell the Coast Guard to find us? NOAA Corps Officers maintain paper charts as a back up method. At the time this photo was taken the Officer was predicting our location in 30 minutes and in 60 minutes. This prediction is updated at regular intervals so that we have a general area to report in the case of an emergency. Officer Gilman completes this task during his shift.
Have I mentioned that the NOAA Corps Officers onboard the Dyson are awesome? They’re so great they let me steer the boat for a little while! In the photo Lt. Ostapenko teaches me how to maintain the ship in a constant direction. The wheel is very sensitive and it took some time to adjust to amount of effort it takes to turn left or right. We’re talking fingertip pushes! The rudder is so large that even just a little push left or right can make a huge difference in the ships course.
Since beginning our survey I’ve only missed being on the Bridge for one trawl. Because I have paid very close attention during those trawls Scientist Darin is now allowing me to record some data. I am entering information about the net in this photo. Survey Tech Allen is making sure I do it correctly!
There are so many other things on the Bridge that deserve to be showcased. The ship can be controlled from any one of four locations. Besides the main control center at the front of the Bridge, there are control stations on either side of the ship, port and starboard, as well as the aft (rear). There is the radar system, too. It is necessary so the Officers can determine the location of other vessels and the direction they are traveling. As I’ve been told, their #1 job responsibility is to look out the windows and make sure we don’t run into anything. They are self-proclaimed nerds about safety and that makes me feel very safe!
Did you know? The NOAA Commissioned Officers Corps is one of the seven uniformed services of the United States. There are currently 321 commissioned officers.
“Whatever,” you shrug.
“Just a fish,” you scorn.
“He’s slimy and has fish for brains,” you mock.
Well, what if I told you that guy there was worth almost one billion dollars in exports alone?
What if I told you that thousands of fishermen rely on this guy to provide for their families?
What if I told you that they were the heart of the Sub-Arctic food web, and that dozens of species would be threatened if they were to disappear?
What if I told you they were all secretly trained ninja fish? Ninja fish that carry ninja swords strapped to their dorsal fins?
Then I’d only be wrong about one thing.
Taina Honkalehto is the Chief Scientist onboard the Oscar Dyson. She has been studying Pollock for the last 22 years. I asked her what was so important about the fish.
“They’re the largest single species fishery in North America,” Taina says. That makes them top dog…err… fish… in the U.S. fishing industry.
“In the U.S. they are fish sticks and fish-wiches (like Filet-o-Fish from McDonalds). They’ve become, foodwise, what Cod used to be… inexpensive, whitefish protein,” Taina continues. They’re also the center of the sub-arctic food web. Seals, walruses, orca, sea lions, and lots of larger fish species rely on Pollock as an energy source.”
But they aren’t just important for America. Pollock plays an important role in the lives of people from all over the Pacific Rim. (Remember that the Pacific Rim is made up of all the countries that surround the Pacific Ocean… from the U.S. and Canada to Japan to Australia to Chile!)
“Pollock provide a lot of important fish products to many countries, including the U.S., Japan, China, Korea, and Russia,” Honkalehto says.
Making sure we protect Pollock is REALLY important. To know what can go wrong, we only have to look at the Atlantic Cod, the fish that Cape Cod was named after. In the last twenty years, the number of Atlantic Cod has shrunk dramatically. It’s cost a lot of fishermen their jobs and created stress in a number of families throughout New England as well as tensions between the U.S. and Canada. The U.S. and Canada share fish populations.
The primary job of the Oscar Dyson is to sample the Pollock population. Government officials use the results to tell fishermen what their quota should be. A quota is a limit on the number of fish you can catch. The way we gather that data, though, can be a little gross.
The Aleutian Wing Trawl (or AWT)
The fishermen guide the massive Aleutian Wing Trawl (or AWT) onto the deck of the ship. The AWT is a 150 meters long net (over one and a half football fields in length) that is shaped like an ice cream cone. The net gets more and more narrow until you get all the way down to the pointy tip. This is known as the “cod end,” and it’s where most of the fish end up. Here’s a diagram that XO (Executive Officer) Kris Mackie was kind enough to find for me.
The AWT is then hooked onto a crane which empties it on a giant mechanical table. The table has a hydraulic lift that lets us dump fish into the wet lab.
Kids, whenever you hear the term “wet lab,” I don’t want you to think of a water park. Wet lab is going to mean guts. Guts and fish parts.
In the wet lab, the contents of the net spills onto a conveyer belt… sort of like what you see at Shaw’s or Market Basket. First we sift through the Pollock and pull any odd things… jellyfish, skates, etc… and set them aside for measurement. Then it’s time to find out what sex the Pollock are.
Genitals on the Inside!
Pollock go through external fertilization (EF). That means that the female lays eggs, and the males come along and fertilize them with their sperm. Because of that, there’s no need for the outside part of the sex organs to look any different. In science, we often say that form follows function. In EF, there’s very little function needed other than a hole for the sperm or egg cells to leave the body.
Because of that, the only way to tell if a Pollock is male or female is to cut them open and look for ovaries and testes. This is a four step process.
Step 1: Slice open the belly of the fish.
Step 2: Push the pink, flippy floppy liver aside.
Step 3: Look for a pair of lobes (a bag like organ) that is either purple, pink, or orange-ish. These are the ovaries! If you find this, you’ve got a female.
Step 4: If you strike out on step 3, look for a thin black line that runs behind the stomach. These are the testes… As Tom Hanks and Meg Ryan might say, you’ve got male.
Then the gender and length of the fish is then recorded using CLAMS… a software program that NOAA computer scientists developed for just this purpose. With NOAA, like any good science program, it’s all about attention to detail. These folks take their data very seriously, because they know that so many people depend on them to keep the fish population safe.
On the first day aboard the Oscar Dyson, we were trained on all matters of safety. Safety on a ship is often driven by sirens sounded by the bridge. Here’s a list of calls, what they mean, and what you should do when you hear them:
What you hear…
What it means…
What you should do…
Three long blasts of the alarm:
Man Over Board
Report to safety station, be counted, and report in to the bridge (unless you’re the one that saw the person go overboard… then you throw them life rings (floaties) and keep pointing at them).
One long blast of general alarm or ship’s whistle:
Fire or Emergency onboard
Report to safety station, be counted, and report in to the bridge. Bring Immersion Suit just in case.
Six or more short blasts then one long blast of the alarm:
Grab your immersion suit, head to the aft (back) deck of the ship, be counted, and prepare to board a life raft.
The immersion suit (the thing that makes me look like lobster gumby, above) is made of thick red neoprene. It has two flashing lights also known as beacons… one of them automatically turns on when it hits water! This helps rescuers find you in case you’re lost in the dark. It also has an inflatable pillow behind your head to help keep your head above water. Mostly just wanted to wear it to Starbucks some day.
Another thing I can tell you about life aboard the Oscar Dyson is that there is plenty to eat!
kind of awesome. For one thing, there is a never ending supply of food in the galley (the ship’s cafeteria). Eva is the Chief Steward on the Oscar Dyson (though I call her the Head Chef!).
You’ll never go hungry on her ship. Dinner last night? barbeque ribs and mac and cheese. Yesterday’s lunch? Steak and chicken fajitas. And this morning? Breakfast burritos with ham and fruit. I know. You were worried that if I lost any weight at sea that I might just disappear. I can confirm for you that this is absolutely not going to happen.
Tune in next time when I take you on a tech tour of the Oscar Dyson!
If you’ve ever been fishing, be it on a lake, river or stream, you know it is not productive to fish all day in a spot where they aren’t biting. If the fish aren’t biting in one spot, you would most likely pack up and move to a different spot. Now imagine trying to fish in an area that is 885,000 square miles. The equivalent to trying to find a needle in a haystack! Luckily, the Oscar Dyson has sophisticated equipment to help us determine where the fish are hanging out. Allow me to introduce you to a very important location on the ship – The Acoustics Lab.
When you enter The Acoustics Lab, you’ll immediately see a wall of nine computer screens. The data shown on the screens help Chief Scientist Taina and Fishery Biologist Darin make the key decision of where we will deploy the nets and fish. What information is shown on the screens? Some show our location on the transect lines we are following, which is similar to a road map we would use to get from point A to point B on land. The transect lines are predetermined “roads” we are following. Another screen tells us which direction the boat is heading, barometric pressure, air temperature, surface temperature, and wind direction and wind speed. The most technical screens show the data collected from transducers attached to the bottom of the ship on what is referred to as the Center Board. There are five transducers broadcasting varying frequencies. Frequency is the number of sound waves emitted from a transducer each second. The Dyson transducers emit sound waves at 18kHz, 38kHz, 70kHz, 120kHz and 200kHz (kHz= kilohertz). Why would it be necessary to have five transducers? Certain organisms can be detected better with some frequencies compared to others. For example, tiny organisms like krill can be seen better with higher frequencies like the 120kHz compared to the lower frequencies. Also the lower frequencies penetrate farther into the water than the higher frequencies so they can be used in deeper water. Having this much data enables the scientists to make sound decisions when choosing where to fish.
Each time I share a blog post with you I am going to focus on one area of the ship so you can get acquainted with my new friend, Oscar Dyson. I’ll begin sharing about my stateroom and the lounge. I was very surprised by the size of my room when I arrived last Thursday. My roommate is Alyssa, a Survey Tech. You will learn more about her journey to the Dyson later. She has been on the ship for a while so she was already settled in to the top bunk which put me on the bottom bunk! The beds are very comfortable and the rocking motion of the ship is really relaxing. I’ve had no trouble sleeping, but then again, when have I ever had trouble sleeping?! We have our own private bathroom facilities, which is a definite bonus. Take a look at our room.
Alyssa and I are on opposite shifts. She works midnight to noon and I work 4:00pm to 4:00am. There is a little bit of overlap time where she’s off and I haven’t gone to work yet. This is quite common for all of the people on the ship. This is a twenty-four hours a day, seven days a week operation. Someone is always sleeping and someone is always working. Fortunately there is a place where we can hang out without bothering our roommates. The Lounge is a great place to kick back and relax. There are comfy chairs and a very large couch and a television with the ability to play dvd’s or video games. Over the years people have brought books with them and then left them on the ship so we have an enormous library. Sometimes there are people just reading in the Lounge and other times a group of us will watch a movie together. There is one important rule of showing movies…if you start a movie you have to let it play all the way out. Even if you get bored with it or need to leave you must let it play because someone may be watching it in their room. It would be rude of us to continually shut movies off an hour into them!
Career Connections: ST Alyssa Pourmonir
Alyssa hails from Pennsylvania. During her senior year of high school she chose to further her education at the Coast Guard Academy. She spent three years studying with the Coast Guard, but ultimately graduated from SUNY Maritime this past January. Alyssa landed a 10 week internship with a NASA facility in Mississippi. During the course of her internship she learned of an opportunity with NOAA. This position would be a Survey Tech, traveling on one of NOAA’s many ships. She arrived at the Dyson only a few weeks before I did.
Alyssa has many responsibilities as a Survey Tech. She assists with the deploying and recovery of the CTD instrument, helps process fish in the wet lab, completes water tests, and serves as a liaison between the ship’s crew and its scientists. When a trawling net is deployed or recovered, Alyssa is on the deck to attach or detach sensors onto the net. She also looks for safety hazards during that time.
When asked what the best part of her job is she quickly responds learning so much science is the best! As a Survey Tech, she gets the chance to see how all the different departments on the ship come together for one mission. She works closely with the scientists and is able to learn about fish and other ocean life. On the other hand, she also works side-by-side with the ship’s crew. This allows her to learn more about the ship’s equipment. Being the positive person she is, Alyssa turned the hardest part of her job into a benefit for her future self. Adjusting to 12 hour shifts has been a challenge but she noted this can also be helpful. When she is super busy she is learning the most and it also makes the time go faster.
Looking ahead to her future, Alyssa sees herself getting a Master’s Degree in a science related field. Some areas of interest are oceanography, remote sensing or even meteorology. Alyssa’s advice for all high school students: STUDY SCIENCE!
Did you know?
Lewis Richardson, an English meteorologist, patented an underwater echo ranging device two months after the Titanic sunk in 1912.
It’s 4 in the morning. I make my way into the cave. The cave is the computer lab. On one wall the size of my classroom whiteboard, there are nine computer monitors, each one regularly updating with information about the fish under the boat. We’ll talk more about the tech on another day. Today is my first trawl. A trawl is when we drop a net and haul up whatever we can catch.
I’m still getting my head around a cup of coffee when Alyssa comes in wearing a hard hat and life vest.
“In about 20 minutes, I’m going to need another hand on deck wearing this.” She points to her gear.
I nod. “Where do I find that?”
Alyssa politely tells me where the gear is. I remember that I’m not supposed to go out on deck when they’re hauling up the net… at least not yet. “Who do you want me to tell?” I say.
“Nate would be great! Nate or Darin!” she says, referring to a pair of scientists… one of whom is going off duty (and probably going to sleep) and another who is coming on (and likely just waking up). She grabs some large tool that I can’t name and heads off. Alyssa, like a lot of the crew, is friendly and upbeat in the mess hall (the cafeteria), but is completely focused and efficient on the job, with an eye towards safety and getting the job done.
Our first trawl is the Marinovich Net. It’s a smaller net, but still takes several fishermen and a winch to bring up. It’s a fairly fine net, with holes about the size of a ping pong ball. In our first trawl of the trip, we mostly catch jellyfish. These aren’t your typical, East Coast jellies, though. Some of them are the size of basketballs, and you can see the fish THEY’VE caught through their see-through membrane (their skin!).
We ended up hauling in over 500 pounds of Jellyfish!
It’s not a bad first catch, but NOAA scientists aren’t content with that. Hanging on the side of the Marinovich are smaller “pocket” nets. This is where we find out what the Marinovich missed. Nate explains to me that, while we are mainly studying Pollock, there’s other valuable data that can be gleaned (collected) in the process. Other scientists studying Krill populations will be grateful for the data.
The pocket nets are labeled, and each net is placed in a labeled bucket. Then I grab a pair of tweezers and start sorting. It’s mostly krill… skinny shrimp-like organisms with beady black eyes. These tiny invertebrates, altogether, make up millions of metric tons of biomass, according to Misha, our resident Russian scientist on board. Biomass is the amount, by weight, of living things in an ecosystem.
Nate asks me to count out 100 krill with my tweezers, which is kind of like counting out 100 tiny pieces of wet spaghetti. Nate places the 100 on a scale and comes up with a mass of 5 grams. He then measures the rest of the krill, and uses the mass of the original 100 as a way to gauge the total number of krill caught in the pocket net.
What stands out to me about this whole process is the attention to detail. That each pocket is carefully sorted, measured, and entered into a computer base. There’s no “-ish” here. I’m not asked to sort “about a hundred.” Not only are the contents of each pocket net measured, but we make sure to note which pocket had exactly how much.
Some of the catch isn’t Krill, however. Sandi calls me over to see how she measures a tiny rock fish. Sandi is a marine biologist who studies reproduction in Pollock. With a gleam in her eyes she explains what’s so great about getting different size young in the net.
“What it means is that it’s possible that some of these fish might be from further away… and we don’t know how they got here, when they got here, or where they came from. And that’s exciting! We weren’t expecting that and it gives us a whole new set of questions!”
I get asked by a lot of kids “how do scientists know that?” My long answer is exactly this. That good scientists DO sweat the small stuff, they make sure that every little variable is accounted for, and collect massive amounts of data. They look for any possible error that might throw off their results or call their conclusions into question. They do the hard work of truly understanding.
So when I hear folks say they don’t believe something simply because it’s inconvenient for them… maybe it challenges a belief that they’ve clung to for no better reason than not wanting to be wrong… I just want to say “Did you do the work? Because I know some people who did.”
And this holds true for all the scientists I’ve been lucky enough to know. Whether they were counting krill, measuring background radiation, or looking for Dark Matter.
By the way, my short answer on “How do scientists know that?” They did their homework.;)
It’s the morning of our third day at sea. It’s taken some getting used to… the first piece is the motion of the boat. Any 8th graders that went on “Untamed!” with me at Canobie Lake Park know that I’ve got some limits as to how I handle a lot of “movement.” The first 8 hours onboard the Oscar Dyson were rough. I thought I might get sick at any moment! But over time, the body figures it out… It’s like your body just says “Oh, this is just what we’re doing now…” and gets OK with it. Now going to bed is like being rocked to sleep by mother earth. 🙂
The next, very different thing about life on the Bering Sea is time. My schedule is from 4 a.m. to 4 p.m… which in some ways is good. 4 a.m. in Alaska is 8 a.m. Eastern Time (Boston Time). So coming home won’t be that tough. The weird thing is going to sleep. This is the view out my window at 11:00 at night.
This is, of course, because the earth has that big old tilt of 23.4 degrees. This is why Alaska is known as “The Land of the Midnight Sun.” Well, we’re a little more than a month past the summer solstice, and we’re not currently above the Arctic Circle. So the sun DOES eventually go down… around Midnight! That means that I need to go to sleep during the daylight. Sometimes as early as 8 p.m.! And that means I need a lot of shades… Shades for my window, shades for my bed, even shades for my head!
We live in an amazing time, where we can travel about the planet, see the extremes that are possible under the physics of this world, and communicate that experience in the same day. Tune in next time when I tell you how to tell the gender of a Pollock. Hint: You can’t just lift their tail!
Before we get into detail about the mission, let’s think about the Oscar Dyson’s geographical location. It is important for us to understand this background knowledge so that we may appreciate the scientific research conducted by NOAA. Most of you have gathered that I am aboard the Dyson somewhere off the coast of Alaska. Our survey began and will end at port in Dutch Harbor, Alaska. Where is Dutch Harbor? Let’s take a look at a map…
Dutch Harbor is on the island of Unalaska in the Aleutian Islands. We will take a scientific look at the Aleutian Islands before we learn about the Bering Sea. The Aleutian Islands separate the Bering Sea from the Pacific Ocean. How did this chain of islands come to be? Continental drift and volcanoes! The Pacific Plate moves northward and has been pushing against the North American Plate, which moves southward, for millions of years. The North American Plate is much less dense than the Pacific Plate and has been riding up onto the Pacific Plate. Here is an image that shows this action.
As you can see in the diagram, the Aleutian Islands are formed by volcanic eruptions along the area where these two plates collide. As I read in the book The Bering Sea and Aleutian Islands: Region of Wonders, “During an eruption, lava, cinders, and ash burst through the earth’s surface at points of weakness in the globe’s mantle, caused by the collision of the plates, and each volcano leaves a telltale conical peak. Many of those eruptions have occurred below the surface of the sea, and only the tops of the mountains poke out of the water, making up many of the Aleutian Islands.” This is how the island of Unalaska came to be, thus Dutch Harbor was established!
Now we need to investigate the Bering Sea. What are some words we use to describe the Bering Sea? Cold, stormy, bleak, productive. If you have ever watched an episode of the Discovery Channel’s The Deadliest Catch, you’ve been given a peek at the “cold, stormy and bleak” aspect of the Bering Sea.
What about the “productive” side of this great sea? Three facts: 1. Alaska supplies about half of the total U.S. fishery. 2. The majority of this contribution comes from the Bering Sea. 3. The nation’s largest fishery is the Pollock fishery. NOAA has estimated that the 2012 Pollock catch value is more than $343 billion. Are you beginning to understand how valuable the Bering Sea is to our world?
In order to maintain or increase the value of the sea, management practices must be in place. The North Pacific Fishery Management Council provides advice to NOAA Fisheries. Also, NOAA conducts research cruises in the Bering Sea perform biological and physical surveys to ensure sustainable fisheries and healthy marine habitats. This is the ultimate purpose of the survey I’m joining. We are performing the third leg of the biannual Walleye Pollock Survey in the Bering Sea. In my upcoming blogs, we’ll dive into the technical aspects of the survey. Are you ready to see some sea life? I definitely can’t wait to get my hands on some critters! Prepare for sea selfies!
As I type my blog, I’m sitting on the deck at a picnic table with the cool, crisp air blowing by. We are in transit to our first survey location. We got underway yesterday afternoon and I won’t see land again for many, many days. That is both exciting and scary at the same time! How do you think you’d feel knowing you are miles away from land? Would you worry about your safety? I am fully confident in the crew of the Oscar Dyson. They have been a great group of people to get to know and I’m sure they will take great care of everyone on board the cruise.
Backing up a couple of days, I want to share with you about my journey across North America and my first two days with the Dyson. After taking off from Columbus I made stops in Minneapolis and Anchorage before landing at the airport in Dutch Harbor. All three flights were smooth and I was thankful for a very calm landing in Dutch. The airport there is a real treat! Our pilot had everything under control though. From the airport we came straight to the ship. I was shown to my room and then we took off for supper at The Grand Aleutian Inn’s dining room. I was able to see a few bald eagles that night and we also took a scenic cruise around the two towns, Dutch Harbor and Unalaska. The next morning the other Teacher at Sea, Greg, and I hitched a ride to the Museum of the Aleutians. It was a great place to learn about the history of the Aleutian Islands. We also made stops at Alaska Ship Supply and Safeway. We had to make sure we were stocked up with the essentials (soda and some candy) to get us through the next three weeks!
Our departure from Dutch Harbor was a beautiful one. Many of the crew members commented on what a beautiful day we were having and how extraordinarily warm it was. The deck crew allowed me to stand on one of the front decks to watch the process of undocking and cruising out of the harbor. They wasted no time as we had our first three drills right away. I’m going to save myself some embarrassment and not share the photo of me donning the survival suit. Let’s just say I’m a little too short for it! Later on that evening we received a call in the lounge that the bridge crew was spotting some whales just west of the ship. I was able to reach the bridge just in time to see a few humpback whales breeching and a few dolphins playing in front of us. That short experience made me really look forward to sorting our first catch. What is one critter from the sea you would like to see in person?
Did you know?
There are nearly 40 active volcanoes that mark the line where the Pacific Plate and North American Plate meet.
Welcome to the Seablog! This is where I’ll be posting about my adventures aboard the NOAA Ship Oscar Dyson, as we study the fisheries off the coast of Alaska.
First allow me to introduce myself. My name is Gregory Cook, and I am, as far as I can tell, in the running for Luckiest Guy on the Planet! I teach middle school science and math at the East Somerville Community School to some of the coolest kids I know, and work with some of the best teachers in the country. Go Phoenix!
On top of that, I received acceptance this year with the National Oceanic and Atmospheric Administration’s (NOAA) Teacher at Sea program! NOAA is part of the Department of Commerce, and does research on everything from fish and whale populations to climate change to mapping the ocean floor and coastline!
In their Teacher at Sea program, I get to work with world class scientists, be a part of real-world research, learn about amazing careers, and share that knowledge with my students. In a small way, I get to share with you the exploration and study of this great planet. What else do you want out of life? A pony? I think not, good sir!
The Oscar Dyson is a ship built by the U.S. Government (Your tax dollars doing great work!) to study the Earth’s oceans. It’s over two-thirds of a football field long and almost fifty feet wide. It can deploy (or send out) over five kilometers (more than three miles!) of cable, It has two massive winches for launching scientific study packages. It can use something akin to Doppler Radar to tell you about what’s in the water beneath us and what the sea floor beneath THAT looks like.
Wanna see how they built it? Of course you do!
See Video Credits for Source Material
The first thing you need to know about Alaska is its name. It comes from the Aleutian word Alakshak, which means Great Lands or Peninsula… the entire state, in the end, seems to be named after the great Alaskan Peninsula that juts out into the Pacific Ocean.
If you’re one of my students, you’re probably asking “How…?”
Well, The Alaskan Peninsula forms in a Subduction Zone. That means that the Pacific Plate is diving underneath the North American Plate. This creates some beautiful upthrusts that you and I know as mountains… or, in the case of the Aleutians,… Islands! Geologists think The Aleutians are about 37 Million Years Old, formed by volcanic activity.
As a matter of fact, the Island I’ll be sailing from, Unalaska, was created this very way. You might remember (from 6th grade if you’re a Somerville kid!) Oceanic crustal plates are more dense than crustal plates, so they dive under them, pushing the mountains and islands up.
When I first heard I was sailing out of Unalaska, I wondered what was so “Unalaska” about it… like… were they Yankees fans or something?
It turns out that in the Aleutian language (the language of the Aleuts… the native people of the area) placing “Un-” in front of a word means “near.” So Unalaska means “Near the Peninsula.” You could say that I live “Undunkindonuts.” (Though, yeah, I’m a Starbucks guy).
OK, back to Geology…
So it turns out that a great deal of the Bering Sea is over the continental shelf of North America. What that means is that the sea is more shallow than the Pacific.
What THAT means is that all the good nutrients that run off of the land… from the rains and rivers… can support a huge amount of sea life. The Bering sea is one of the most productive fisheries in the world… It is teeming with life!
If you’ve ever had Fish Sticks or McDonald’s Fillet o’ Fish, you’ve probably had some form of Pollock. They grow quickly, they die young, and have a lot of offspring. They also represent almost 2/3 of all the groundfish (fish that live near the bottom of the sea) caught in Alaska 2012.
So to say Pollock are important is kind of like saying bread is important… They have a huge impact on our lives here in the United States. So it’s important we look in on them every now and then, and make sure they’re doing ok… So we can eat them. 😀
That’s what I’ll be doing up there in Alaska. Exploring the Bering Sea, and looking in on our good friend, Mr. Pollock. I hope you can come along for the ride. 😀
Hello from beautiful Southern Ohio! My name is Kacey Shaffer and it is an honor to be an NOAA Teacher at Sea for the 2014 Field Season. I am thrilled to be sharing this once-in-a-lifetime opportunity with you. In a few days I’ll be flying across North America to spend nineteen days aboard the NOAA ship Oscar Dyson. Our mission will be to assess the abundance and distribution of Walleye Pollock along the Bering Sea shelf.
Next month I’ll begin my eighth year as an Intervention Specialist at Logan Elm High School in Circleville, Ohio. I teach Biology and Physical Science resource room classes and also co-teach in a Biology 101 class and Physical Science 101 class. Three summers ago I was able to participate in Honeywell’s Educators at Space Academy, held at the U.S. Space and Rocket Center in Huntsville, Alabama. That experience enabled me to bring a wealth of information and activities back to my students and colleagues. Because I had such a wonderful experience at Space Academy, I knew I would soon be seeking out other opportunities to perform hands-on work and gain knowledge not available in my geographic area. I was very excited when I found the NOAA Teacher at Sea program and applied immediately. When the congratulatory email arrived I acted like a little girl on Christmas morning, jumping up and down and squealing!
Not only do I love adventure that is related to my teaching career, I love adventure in general! Two summers ago I had the privilege of joining one of Logan Elm’s Spanish teachers and four of her recent Spanish 4 graduates on a nine day tour of Spain. We were immersed in culture and history in several cities from Madrid to Barcelona. It was a wonderful experience and I really hope to travel abroad again. Last month the same Spanish teacher escorted four more recent graduates to Puerto Rico for a five day stay. Thankfully she felt I had behaved well enough in Spain to be invited on this trip! Our trip to Puerto Rico was very different from our travel in Spain. We were able to go ziplining in La Marquesa, hiking in El Yunque (which happens to be the U.S. National Park Service’s only tropical rain forest), and kayaking in Laguna Grande near Fajardo. The most amazing experience was kayaking at night in Laguna Grande. Why would you kayak at night? Because that is the home of a bioluminescent bay! You can learn more about this ocean phenomena here. I am very thankful to be able to travel as much as I do!
If I were driving to the Oscar Dyson, it would be about a 5,000 mile trip one way! I’m really glad the journey will be via airplane. I’ll be meeting the ship in Dutch Harbor, Alaska. Does that name sound familiar? Dutch Harbor is the home base of the Discovery Channel’s “The Deadliest Catch.” It is a very small town on one of the many islands that are collectively called the Aleutian Islands. From Dutch Harbor we will sail into the Bering Sea and begin our work. From the information I’ve read, we’ll spend our days gathering information about Walleye Pollock. Through my preparations I’ve gathered this is important because Walleye Pollock is one of the largest fisheries in the world. Why would Walleye Pollock be important to me or my students? This fish is often used in imitation crab or fried fish fillets. We could be eating this species the next time we have fish sticks for supper! For greater detail on Alaskan Walleye Pollock check out the NOAA’s FishWatch page here.
The next time I write to you I’ll be aboard the mighty Oscar Dyson. In the mean time I’ll continue to gather warm clothes and search for a box of seasickness medicine. As I’m packing I may need some advice. If you were leaving home for three weeks, what is the one item you wouldn’t leave without? Remember, I’ll be at sea. My cell phone will be rendered useless and my access to the internet will be limited.
Geographical Area of Cruise: Bering Sea South of Russia
Date: July 15, 2014
Weather Data from the Bridge
Wind Speed: 10.84 kt
Air Temperature: 10.2 degrees Celsius
Barometric Pressure: 1023.0
Latitude: 5822.3417 N
Longitude: 17253.5563 W
Science and Technology Log:
Deploying a CTD
I learn new operations each day I am aboard the Oscar Dyson. There are numerous people aboard the ship that make the whole operation of working on a research vessel possible. Survey technicians, Alyssa Pourmonir and Walter (Bill) Potts, help the scientists with the survey process and communicate between the bridge, deck crew, and the science team during a trawl. Each day, sometimes twice daily, the survey techs, will deploy a CTD (conductivity temperature depth) device to the bottom of the ocean floor. The device measures salinity (how much salt is in the water), temperature, fluorescence (chlorophyll content of plankton), oxygen, and turbidity (how clear or murky the water is) of the ocean water. The CTD sends this information electronically to a computer program which then displays the data and graph for scientists to evaluate.
As with trawling for fish, this process requires collaboration among crew members. The NOAA Corps Officers control the position of the ship from the bridge, and members of the Deck Department control the winch that lifts the CTD device off the deck and into the sea. It takes two deck hands to help the survey tech navigate the device attached to the winch (the two deck hands are firmly attached to the boat by a rope attached to a belt) off the side of the boat and into the sea, and one deckhand to run the winch from the deck above.
Once the device has been deployed into the sea, the survey tech, using a computer program, will record the data as the CTD is lowered and raised. When the device surfaces and is returned to the side deck of the ship, the survey tech takes a sample of the water, which is collected in one of the bottles attached to the CTD device. This water is then sealed and brought back to the lab in Seattle, Washington for further testing. Although the device reports the salinity of the water while deployed in the ocean, the scientists want to calibrate the salinity of the water sample to check for accuracy. They can perform more detailed tests on the water in their labs.
So why does NOAA want to collect this data? Analyzing and comparing the data against previous year’s data will assist in checking the health and welfare of the ocean. It also helps scientists discover more information about the different layers (depths) of the oceans. It lets us know how the ocean is changing over time and gives us more information about how our climate changing.
How do scientists organize their data?
You probably deduce that scientists mainly use a computer to organize their data and you would be correct. However, they also record data in a journal. Journals are extremely essential and include appropriate headings, such as what the scientists are working on, the date and the time. Time and dates are imperative to keeping accurate records and some scientists draw pictures with labels to help describe their findings. This journal does not leave the Acoustics Lab during time at sea. My experience, working with the scientists, aboard the Oscar Dyson, allows me to easily relate “real world applications” into my daily curriculum and lesson planning. I have my students journal in both their math and science classes. And now I can show my students, proof that scientists actually do the same thing. Thanks NOAA and the crew of Oscar Dyson!
I finally experienced a day with little cloud coverage. The sunrise is breathtaking. It has been rising around 6:40 am each morning. The crew does not see the sun very much on the Bering Sea as it is mostly cloudy in this area. The sea has been relatively calm. Thankfully, I have not felt any signs of sea sickness. The boat has a gentle rocking motion that, if I sit still long enough, can lull me to sleep. I miss my family, friends, and my dog, however, I know I will be home soon. I empathize with the crew whom work on the boat full-time and seldom see their loved ones. Three weeks is plenty of time for me, although this is truly a voyage of a lifetime. Twelve hour shifts are not bad as long as I keep busy. After my shift is over, I have been playing cards or Farkel with some of the science crew, mostly Nate, Emily, and Alyssa. I even learned how to play Cribbage. Dinner is at 5:00 pm and then I will watch a movie, visit the bridge, or work on my next blog. My self-appointed bed time is 7:30 pm, as the morning comes quickly.
Each day while at sea, the ship continues to trawl the Bering Sea, as the scientists search for pollock using the sonar screens. Trawling is like mowing the yard; we cover the ocean in the same manner, moving north and south covering a large expanse of the Bering Sea starting at Dutch Harbor and by the end of the third leg, possibly ending in Russia territory. When the ship trawls north, I cannot access the internet due to the position of the receiver on top of the ship. When the ship trawls south, the internet is available. The crew, myself included, looks forward to southbound trawling across the Bering Sea. Internet access opens up communication with both family and friends, not to mention the World Cup standings. Maybe next time, USA!
Each day, “News for the day” is posted in the hallway on the galley level. It includes weather, happenings aboard the ship, and usually a funny cartoon or riddle. The following is a riddle I thought you would enjoy:
Each morning I appear to lie at your feet. All day I follow no matter how fast you run. Yet I nearly perish in the midday sun. What am I?
Scroll to the bottom of my blog for the answer!
Getting to know the Crew:
Over the past week and a half, I had the opportunity to talk to several crew members aboard the Oscar Dyson, including the NOAA Corps Officers. Recently, I talked with the Commanding Officer and the Chief Bosun .
The Commanding Officer (CO), CDR Arthur Stark, is in charge of everyone and everything on the boat. He and his family currently live in Port Angeles, Washington. During college he worked on the Coho Ferry, which ferries from Port Angeles, WA to Victoria, Canada, a 22 mile trip each way. A year after graduating from college, with a degree in Fish and Wildlife Management, he secured a job as a deck hand aboard the NOAA Rainier. While working at sea, he learned about the NOAA Corps, and their officer training program. He applied, was accepted, and completed the 90 day program. He started out as a junior officer and worked his way up to the Commanding Officer position. He has been with NOAA for over 17 years. All NOAA Corps Officers rotate two years at sea and three years on land. He had the opportunity to help with the aftermath of the Deep Water Horizon incident, which occurred in 2010, in the Gulf of Mexico. He remembers that day, since it was the same day his daughter was born. He offered some good advice to students that want to pursue a career with the NOAA Corps or ocean related careers; look for volunteer opportunities and summer camps that deal with marine life. He said to make sure to spend time outdoors and be involved.
The Chief Bosun or head fisherman is Kirk Perry. He lives in California and has been with NOAA for over ten years. Before his work with NOAA, he worked on fishing boats, with the fire department, and worked in construction. He has a lot of interesting stories about his adventures at sea. If you need help on deck, he is the man to ask. Recently, we caught about three dozen Pacific Ocean Perch otherwise known as Rockfish. Kirk entered the wet lab, while we where processing the catch, took out a large cutting board and his personal, very sharp, filet knife, and started filleting the rockfish like a professional. He told me he has been fishing and filleting fish since he was 10 years-old. When finished, Kirk delivered the rockfish filets to the head galley chef, Kimrie Zentemeyer, to use for dinner. She is going to make fish and chips. Scrumptious, fresh fish, from the sea—to my table!
More to come, in my next blog, about other crew members and NOAA Corps Officers I spoke with during my journey aboard the Oscar Dyson. Thank you for following me!
Meet the Scientist: Nate Lauffenburger
Title: Scientist III—Contracted by Ocean Associates (working with NOAA)
Job Responsibilities: Help develop software to automatically process images from Cam-Trawl, a camera that gets hooked to the trawl net and takes pictures of fish as they are being caught. Completes acoustic analysis of fish near bottom of the sea and participates in fishing surveys.
Education: Bachelor’s Degree in Math & Physics, State University of New York (SUNY) at Geneseo; Master’s Degree in Oceanography, University of Washington
Hometown: Buffalo, New York
Current Residence: Seattle, Washington
Why pursue this career? Math and science always came easy to him; he participated in an internship at the University of Rhode Island in oceanography and thoroughly enjoyed the experience and wanted to continue on that path.
Long term goals: He is 27 years-old and is just starting his career. He wants to continue to learn his trade and work in the field of ocean and fisheries.
Did you know?
Did you know the Smooth Lumpsucker is a different family from the Pufferfish but uses a similar defense mechanism?It fills itself up with water so that it cannot be easily swallowed by a predator.
Did you know that the Pacific Ocean Perch is not a perch? Perch are freshwater fish. The Pacific Ocean Perch is a type of Rockfish.
Stern-back of the boat
Bow-front of the boat
Port-left of the boat (red light flashing)
Starboard-right of boat (green light flashing)
Mess Hall- Eating area for crew
Bridge-control room where NOAA Corps Officers navigate the ship
Geographical area of cruise: Bering Sea and Gulf of Alaska
Date: July 1, 2014
Greetings from Dover, Delaware, the first state to ratify the United States Constitution! My name is Mary Murrian and I teach math and science to a wonderful group of fifth grade students at William Henry Middle School. My journey will begin early in the morning on Wednesday, July 2, 2014. My son, Robert–an upcoming junior at the University of Delaware, is driving me to the Philadelphia airport at 3:00 am in the morning. After transferring planes in Chicago, Illinois and then again in Anchorage, Alaska, I will finally make land at my final destination, Dutch Harbor, Alaska.
If you are a Deadliest Catch fan you will recognize Dutch Harbor as the home base for the popular television show on the Discovery Channel. I will be aboard NOAA Ship Oscar Dyson, a NOAA (National Oceanic and Atmospheric Administration) ship. I have the wonderful opportunity to work with the crew and scientists aboard the Oscar Dyson to research and determine the abundance and health of walleye pollock, one of the largest fisheries in the world. If you have ever eaten fish sticks or imitation seafood, most likely you have tried pollock!
Thanks to the NOAA Teacher at Sea program, I am afforded this wonderful opportunity to work hands-on, learning the science involved in research aboard a NOAA ship. I currently teach a unit on ecosystems, where my students learn about the ecosystem around them and the interrelationships between organisms in an environment focusing on food chains, food webs, and environmental factors that play a role in an ecosystem. This experience will enhance my knowledge of marine ecosystems and the important role the fish play in supporting a healthy and sustainable environment. I look forward to learning and growing through my participation with experts in their field. I want to gather as much information as possible, in order to bring it back to my classroom and share my real life experience with my students this upcoming school year and years to come. What a wonderful way to bring real-life data and experiences to my students.
I have been asked numerous times if I am scared or nervous to be aboard a ship sailing on the Bering Sea. My response, NO! I am thrilled. I cannot wait for my journey to begin. I have cruised to Alaska before, however not as far north as the Dutch Harbor area and I was on a recreational cruise ship. It was beautiful and the scenery was amazing. I never saw ice as blue as I did when we crossed Tracy Arm fjord. A fjord is a typically long, narrow valley with steep sides that are created by advancing glaciers (http://oceanservice.noaa.gov/education/kits/estuaries/media/supp_estuar04_fjord.html). The trip, although freezing, was amazing. I also found out that glacial ice often appears blue because of years of compression gradually making the ice denser over time, forcing out the tiny air pockets between the crystals. When glacier ice becomes extremely dense, the ice absorbs a small amount of red light, leaving a bluish tint in the reflected light (http://nsidc.org/cryosphere/glaciers/quickfacts.html). Super cool!
I look forward to my upcoming experience, a trip of a lifetime. There is more to come, I hope you will continue with me on my journey across the Gulf of Alaska and the Bering Sea! Watch out Alaska, here I come!
NOAA Teacher at Sea
Sailing Aboard NOAA Ship Oscar Dyson
June 8 — 26, 2013
Mission: Pollock Survey Geographical area of cruise: Gulf of Alaska Date: May 21, 2013 – Upcoming cruise dates June 6 – 26, 2013 Weather Data from the Bridge: as of 0500 Wind Speed 20.97 kts Air Temperature 5.40°C Relative Humidity 91.00% Barometric Pressure 1,031.50 mb Latitude: 55.72 Longitude:-157.36 Hi, I’m Marla Crouch I live in Issaquah, WA, about 17 miles east of Seattle. I teach Earth Sciences and I am the Robotics Club Adviser at Maywood Middle School, in the Issaquah School District. On June 6, 2013 I will head north to Alaska to begin my adventure as a NOAA Teacher At Sea. I’ll be updating this blog about three times a week, so check back often. Let me know if you have answers to the questions I’ve posted. Science and Technology Log While I am aboard the Oscar Dyson I will be working with the Scientist Team doing a Pollock Survey. The Alaskan Pollock or Walleye is member of the cod family and is the most valuable fish crop in the world. Products made from Pollock were valued at $1 billion in 2010.
During the survey we will be checking population size and characteristics including age and gender. The Science team will calibrate and monitor equipment used to find the schools of pollock that swim in the mid-water depths of the ocean (330 – 985 feet). Samples of the population will be caught using cone-shaped nets.
Personal Log The last time I cruised Alaska’s water, I was on a cruise ship gliding through the Inland Passage along Alaska’s southeast shores. This time I’m headed about 900 miles west to the island of Unalaska, in the Aleutian Islands and the open waters of the Bering Sea and the Gulf of Alaska. My Teacher At Sea experience embarks from Dutch Harbor, AK. Here I will meet the NOAA ship Oscar Dyson; I’ll introduce myself to the ship’s crew and science team and settle in for the 19 day fishery cruise.
Have you ever wondered why ships/boats are referred to as “she?” Answer, no one knows for sure as the origins have been lost in oral history. I’ll be interested in finding out how the Oscar Dyson crew refers to her. The NOAA ship Oscar Dyson is 63.8m long, 15m wide and displaces 2479 metric tons when fully loaded. The Dyson can be at sea up to 40 days and travel 12,000 nmi before replenishing supplies. Okay, Ladies and Gentlemen, your turn to do the math. Tell me what are the dimensions of the Dyson in feet? I’ll help; here is the conversion ratio, 1m: 3.28ft. Next question: convert nautical miles to statue miles 1mi: 1.15nmi.
The Oscar Dyson was launched in Pascagoula, MS in October 2003 and commissioned in 2005 in Kodiak, AK. The mission of the Dyson is to protect, restore and manage the use of living marine, coastal, and ocean resources through ecosystem-based management. The ship observes weather, sea state and environmental conditions, studies and monitors fisheries, and both marine birds and mammals. Check out the video below of the launching of the Dyson. Video courtesy of http://www.moc.noaa.gov/od/ (animation 6) In preparation for my trip I did a little research on Dutch Harbor and the island of Unalaska. Unalaska is one of approximately 100 stratovolcanic islands spanning 1250 miles in Aleutian Islands chain. The Port of Dutch Harbor is the only deep draft, ice-fee port from Unimak Pass west to Adak and north to the headwaters of the Bering Straits. Annually, more than 1.7 billion pounds of seafood are shipped from Dutch Harbor. Island history includes settlements by the Unangan (Aleut) people roughly 9,000 years ago, architectural and cultural influences from Russia, the invasion by Japanese forces and the internment of American civilians in WWII. The WWII Aleutian Campaign is one of the deadliest battles in the Pacific theater. A note for our students studying WWII: check out the National Park Service web site for the Aleutian World War II.
Did You Know? I’ve learned a new word, Williwaw. I think I’ll add this word to our study of Catastrophic Events. What is a Williwaw? You tell me. Here is a hint, if the ship encounters a Williwaw I may be searching for the Dramamine.
Geographical Area of Cruise: Gulf of Alaska and the Bering Sea
Date: May 10, 2013
Weather Data from the Bridge (0200):
W wind 10 kt. Chance of light snow.
Air Temperature 2.6C
Relative Humidity 82%
Barometer 1025.5 mb
Surface Water Temperature 4.30 C
Surface Water Salinity 32.91 PSU
Seas up to 3 ft
Science and Technology Log
As we continue to complete CTD sampling on our last full day at sea, the major change from previous days is that the depth of the Bering Sea has increased dramatically. For the past couple of days we have been riding along the 70 m depth line. We are now casting down to 1,500 m with the ocean bottom currently at 2,298 m.
My previous blogs have focused on the instrumentation and sampling methods used on the cruise. I would now like to introduce you to the members of the science team on board the Oscar Dyson for this cruise.
William (Bill) Floering, Chief Scientist
Education: BS Biology, University of Washington; BS Wildlife Biology, Oregon State University.
Position/Affiliation: Chief Scientist on Cruise, Field Operations Specialist/ NOAA/PMEL/OERD (30+yrs)
Duties on cruise: Oversee the entire cruise operations, objectives, staffing, and mooring deployment. He is constantly “on duty” and serves as liaison between ship personnel and the science team.
Data: Data collected will be used to better understand the physical and biological properties of the ocean water in the Gulf of Alaska and the Bering Sea. PMEL makes this data readily accessible to scientist of many disciplines to use.
Carol DeWitt, NOAA/PMEL/FOCI
Education: BS Biological Oceanography, Florida Institute of Technology
Position/Affiliation: Field Operations Specialist/PMEL/FOCI (25+yrs)
Duties on cruise: Ensures that all of FOCI’s instruments are prepped, shipped to the Oscar Dyson prior to departure, and in working order once the cruise begins. Join in with all other team members in helping to complete onboard operations.
Data: Data collected will be used to better understand the physical and biological properties of the ocean water in the Gulf of Alaska and the Bering Sea. PMEL makes this data readily accessible to scientist of many disciplines to use.
Education: BS Atmospheric Science, University of Washington
Position/Affiliation: Research Scientist, Physical Oceanography Technician (2+ yrs)/ NOAA/PMEL/OERD
Duties on cruise: Mooring deployment and recovery along with CTD water sampling. Join in with all other team members in helping to complete onboard operations.
Data: Data collected will be used to better understand and monitor the physical properties of the ocean water in the Gulf of Alaska and the Bering Sea.
Education: MS Statistics, University of Louisiana, Lafayette
Position/Affiliation: Statistician (19+ yrs)/ NOAA/Alaska Fisheries Science Center (AFSC)
Duties on cruise: Complete CTD water sampling as well as oversee Bongo tows and preservation of tow samples. Join in with all other team members in helping to complete onboard operations.
Data: Some of the data collected by her group will be analyzed by scientist in Poland. Kathy offers her statistical expertise to researchers reviewing collected data. Once data is analyzed it will be used to better understand and monitor the physical properties of the ocean water in the Gulf of Alaska and the Bering Sea.
Education: BS Geology, University of Alaska, Fairbanks
Position/Affiliation: Research, Mooring Technician (5+ yrs)/ UAF Institute of Marine Science
Duties on cruise: Prepare various monitoring instruments for deployment on moorings. Water sampling for nutrients, dissolved inorganic carbon, and dissolved oxygen. Join in with all other team members in helping to complete onboard operations.
Data: Data collected will be used to better understand and monitor the physical properties, including monitoring ocean acidification, of the ocean water in the Gulf of Alaska and the Bering Sea.
Education: Ph.D., Case Western Reserve University
Position/Affiliation: Research Scientist/ Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington (11+ yrs)
Duties on cruise: Oversee the operation and data collection of CTD casts. Additionally, collect nutrient, salinity, DO samples from CTD drops. Join in with all other team members in helping to complete onboard operations.
Data: Data collected will be used to better understand and monitor the physical properties of the ocean water in the Gulf of Alaska and the Bering Sea. Data will also be used collaboratively in fisheries assessment within this geographical region.
Education: MS Fisheries, Oregon State University
Position/Affiliation: Fisheries Research Biologist (25+ yrs)/ NOAA/Alaska Fisheries Science Center (AFSC)
Duties on cruise: Oversee Bongo tows and preservation of tow samples as well as ensure proper collection of chlorophyll samples. Join in with all other team members in helping to complete onboard operations.
Data: Chlorophyll samples will be used to standardize instrumentation used on board. Once data is analyzed it will be used to better understand and monitor the physical properties of the ocean water in the Gulf of Alaska and the Bering Sea. Matt’s research in helping to better understand Pollock fisheries will soon be published in the Journal of Marine Science.
If you are interested in pursuing a career in “marine science”, broadly defined, the collective advice from the science team is as follows: let your passion for studying the Ocean be your drive; experience this field firsthand through internships and volunteer opportunities aboard cruises; diversify your studies so that you have a broad background in several disciplines; through all of these experiences make certain that you truly do have a desire to pursue this field of science.
I would like to take this opportunity to thank Peter Proctor for his time, expertise, and willingness to share his knowledge of the ocean with me. I also appreciated his patience in teaching me the techniques of CTD nutrient sampling, my “job” on the cruise. His humor and wit helped to make the downtime on our cruise enjoyable and always a learning experience.
Finally, I continue to be impressed with the leadership that Bill exhibits on board ship. His efforts ensured that valid “science” research was conducted during the cruise. The data collected, once analyzed, will add to our knowledge base of the ocean waters of the Gulf of Alaska and the Bering Sea. I would like to personally thank Bill for allowing me to have the opportunity to actively work alongside the science research team on this cruise.
In my “science and technology” log above I introduced you to the science crew. In this section, I would like to introduce you to someone who works very hard to keep “everybody happy” on board ship. Frank Ford is Chief Steward aboard the Oscar Dyson for this cruise.
Frank is an experienced chef providing us with nutritional, well balanced, food 24 hours per day. On a ship, meals are served at specific times but everyone works different shifts and therefore is not always able to be at a serving. Therefore, Frank needs to ensure that all of our dietary needs are met regardless of our personal work schedule. As I have indicated in previous blogs, I never went hungry. There is always a wide range of fruit, yogurt, snacks, leftovers, etc. available. Frank also closely monitors the temperament of the crew as we eat our meals in the galley, via his open kitchen, and is always there to chat with us. Thanks Frank for your multiple and varied menu offerings! I know that my students would be very pleased to have Frank Ford as our head chef on campus.
On this cruise I have had the opportunity to not only work with the science team but to also meet and work with members of the NOAA Officers Corp as well as the NOAA deck crew. I have discovered that they come from a variety of backgrounds as well as from all over the United States. However, they all have in common a love for being on the open sea. I am impressed with their candor, openness, and their professionalism. I have made many new friends! Thank you for the opportunity to sail on your ship!
Since leaving Seward, Alaska on April 29th, we have steamed over 2,000 nautical miles (2,300 miles) and traversed from the Gulf of Alaska (North Pacific) into the Bering Sea. This journey has truly been a rewarding and phenomenal educational opportunity for me. I am truly honored to have had the opportunity to be a NOAA Teacher at Sea “student” and truly hope that other teachers, from across the United States, will continue to have this opportunity. Recognizing and understanding the role that the “Ocean” plays in the overall health of our Planet is critical. It is imperative that we provide our students with a robust education along with an understanding and appreciation for the discipline of Ocean science research.
Did You Know?
Seniors, not to worry , I will be back on campus to attend your graduation!
Geographical Area of Cruise: Gulf of Alaska and the Bering Sea
Date: May 5, 2013
Weather Data from the Bridge (0300):
Partly cloudy, S Winds, variable, currently 3.71 knots
Air Temperature 2.8C
Relative Humidity 73%
Barometer 1025.1 mb
Surface Water Temperature 0.10 C
Surface Water Salinity 31.66 PSU
Seas up to 5 ft
Science and Technology Log
Once we completed our mooring work from Gore Point through to Pavlof Bay, we sailed on to Unimak Pass, nearly 400 miles away, and then entered into the Bering Sea. Unimak Pass is a strait (wide gap) between the Bering Sea and the North Pacific Ocean in the Aleutian Island chain of Alaska. Upon arrival at our first station, we started the process of deploying our CTD sampling unit at predetermined points as well as MARMap Bongo casts(discussed in my next blog) when specified, within a region forming a rectangular “box” north of the pass. If you have been following my voyage using NOAA ship tracker, hopefully you now understand why we appeared to have been “boxed in” (I can hear the groans from my students even out here in the Bering Sea). It is important to understand the ocean waters of this region given that it is a major egress between the North Pacific Ocean and the Bering Sea. Therefore it serves as an important pathway between these two water bodies for commercially important fish stock as well as serving as a major commercial shipping route.
A CTD (an acronym for conductivity, temperature, and depth) is an instrument used by oceanographers to measure essential physical properties of sea water. It provides a very comprehensive profile of the ocean water to help better understand the habitat of important marine species as well as charting the distribution and variation of water temperature, salinity, and density. This information also helps scientist to understand how variations in physical ocean properties change over time. The CTD is made up of a set of small probes attached to a large stainless steel wheel housing. The sensors that measure CTD are surrounded by a rosette of water sampling bottles (niskin bottles) that individually close shut by an electronic fired trigger mechanism initiated from the control room on-board the ship. The rosette is then lowered on a cable down to a depth just above the seafloor. The science team is able to observe many different water properties in real time via a conducting cable connecting the CTD to a computer on the ship. A remotely operated device allows the attached water sampling bottles to be closed (sample collected) at selective depths as the instrument ascends back to the surface.
On this cruise, our CTD was equipped to collect real-time water column measurements of conductivity, temperature, density, dissolved oxygen, salinity, chlorophyll levels, and light as the unit traveled down through to a set point just above the ocean floor. Additionally, water samples for determining concentrations of nutrients (nitrate (NO3-1), nitrite (NO2-1), ammonium (NH4+), phosphate (PO4-3), and silicates (SiO4-4), dissolved oxygen, dissolve inorganic carbon, and chlorophyll were measured at specified depths within the water column as the unit was raised back to the surface. Replicate measurements of some chemical constituents measured on the ascent are completed to help support the reliability of the dynamic measurements of these same species made on the drop. All of the nutrient samples are then frozen to -80C and brought back to the lab on shore for analysis. Dissolved oxygen, dissolved inorganic carbon, and chlorophyll samples are also treated according to unique methods for later detailed analysis.
Our first CTD cast from the “Unimak Box” began with my shift, a bit after midnight, on May 3rd and ended 32 hours later on May 4th. The science crew worked nonstop as they completed 17 different CTD casts. Again, it was impressive to see the cooperation among the scientists as each group helped one another complete CTD casts, launch and retrieve Bongo nets, and then collect the many different samples of water for testing as well as the samples of zooplankton caught in the bongo nets. My task was to collect nutrient water samples from each CTD cast. As the water depth increased so did the number of samples that were collected. During our sampling water depths ranged from approximately 50 meters (5 samples) up to 580 meters (11 samples). On our last cast the air temperature was -2.3o C with water temperature reading 2.90 C. Seas were relatively calm and we were able to see many different islands in the Aleutian chain.
It was rewarding to be able to help the team collect water samples for nutrient testing, especially given that we are able to sample many of these same nutrient species in our chemistry lab at Franklin Pierce. I want my students to know that I practiced “GLT” when collecting nutrient samples making certain to rinse each sample bottle and sampling syringe at least three times before each collection. Want to know what “GLT” references…ask one of my students!
My most “interesting” time on board ship happened during our first night of CTD testing along one of the lines of the Unimak Box. At 2:45 am Peter, Douglas, and I were recording flow meter values from the previous bongo net tow on the side quarter-deck. I was writing values down on a clip board as Peter read the values off to me. I happened to glance over the deck towards the sea when I noticed an unusually large wave about 2 meters out from the boat traveling towards us. Suddenly it crashed on top of us knocking us to the deck floor. Water flooded all around us and through the doors of our labs. I immediately grabbed onto one of the ship’s piping units and held on tight as the water poured back off the deck. In an instant the sea was calm again after the “rogue” wave released its energy on our ship. Because Peter and I fell onto the deck our clothes became completely soaked with icy cold seawater. Upon standing, we checked on each other and then immediately began retrieving empty sampling bottles and other lab paraphernalia as they floated by in the water emptying off the deck. Douglas was able to hold-on to the CTD and remained standing and dry under his rain suit. This is the first, and I hope the last, “rogue” wave that I ever experience. Fortunately, no one was lost or injured and we were able to retrieve all of our equipment with one exception…the clip board of data log entries that I was holding!
I must admit that I am disappointed at the limited internet access while on board ship. I find it somewhat disheartening that I have not been able to write the consistent blogs promised to you telling of my adventures. Hopefully this will improve as we change course and you will continue to follow along.
Partly cloudy, Winds 10 – 15 knots
Air temperature: 4.0 C
Water temperature: 5.3 C
Barometric Pressure: 1014.14 mB
Science and Technology Log
The primary mission of this cruise is to deploy and recover moorings in several locations in the Gulf of Alaska and the Bering Sea. These moorings collect data for a group of scientist under the auspices of the Ecosystems & Fisheries-Oceanography Coordinated Investigations (EcoFOCI) which is a joint venture between the NOAA Pacific Marine Environmental Laboratory (PMEL), and the NOAA Alaska Fisheries Science Center (AFSC). Participating institutions on this cruise include NOAA-PMEL, AFSC, Penn State, the National Marine Mammal Laboratory (NMML), and the University of Alaska (UAF). This interdisciplinary study helps scientist better understand the overall marine environment of the North Pacific. This understanding will lead to a better management of the fishery resources of the North Pacific Ocean and the Bering Sea.
To ensure that time at sea is maximized for data collection, a day or so before leaving Seward, Alaska, the science crew begins assembling their various monitoring instruments under the directions of Chief Scientist for this project, William (Bill) Floering, PMEL.
Some of the equipment that will be deployed includes an Acoustic Doppler Current Profiler (ADCP), which measure speed and direction of ocean current at various depths. This data helps physical oceanographers determine how organisms, nutrients and other biological and chemical constituents are transported throughout the ocean. Argos Drogue drifters will also be deployed to help map ocean currents. Conductivity, temperature, and depth (CTD) measurements will be conducted at multiple sites providing information on temperature and salinity data. Additionally, “Bongo” tows will also be made at multiple locations which will allow for the collection of zooplankton. The results of this sampling will be used to characterize the netted zooplankton and help to monitor changes from previous sampling events. In future blogs I will describe these instruments in greater detail.
The furthest extent of our mission into the Bering Sea is very much weather and ice dependent with much variation this time of the year in the North Pacific Ocean. Current ice map conditions can be found at http://pafc.arh.noaa.gov/ice.php.
As I rode in the shuttle bus from Anchorage to Seward, Alaska on Friday, April 27, and then onto the pier where the Oscar Dyson was docked, I was immediately impressed by its size and overall complexity.
Upon arrival I was met by Bill Floering, Chief Scientist on the cruise. He gave me a tour of the overall ship and then I settled into my room, a double. Just like being back in college myself, and being the first to the room, I had my choice of bunks and therefore selected the lower bunk (I did not want to fall out of the top bunk if the seas turned “rough”). Arriving early provided me time to become oriented on the vessel given that I have never been aboard such a large ship before. I also had the opportunity to walk into Seward, AK, with a member of the science team, for a dinner downtown with extraordinary views of the surrounding mountains.
On Saturday, April 27, the rest of the science crew arrived and my roommate, Matthew Wilson, moved in. Matt is from the Alaska Fisheries Science Center (AFSC) based in Seattle, Washington. That evening we traveled into town again for another great dining experience…halibut salad with views of Resurrection Bay.
Sunday, April 28, was a busy day of sorting and setting up various instruments for deployment. Winds were very strong, with snow blowing over the peaks of the mountains, glistening in the brilliant sunshine.
View of Seward Harbor.
Monday, April 29, our day began with a safety meeting followed by our science meeting. At that time we were assigned to our work shift. I will be working from 12 midnight to 12 noon each day during the cruise. Once the ship sets sail, the science crew is working 24 hours per day!
Greetings! My name is Frank Hubacz, and I teach General Chemistry and Environmental Chemistry at Franklin Pierce University where we are celebrating our 50th Anniversary. Our main campus is located in Rindge, New Hampshire near the base of Mount Monadnock; this 3,165-ft. mountain summit is the most frequently climbed mountain in North America. At Franklin Pierce, we encourage our student body of approximately 1400 students to embrace their education and to achieve academic success through the integration of liberal arts and our various professional programs.
I first started teaching biology in 1976; however my interests soon migrated into the study and teaching of chemistry. I have been teaching general chemistry at Franklin Pierce University since 1992. While attending the 2006 National Science Teachers Association (NSTA) Annual Convention in Anaheim, CA I had the good fortune to attend the headline presentation given by Jean-Michele Cousteau. His presentation, entitled “Responsible Living…Because Everything is Connected”, considered the vital relationship between the health of our planet, as monitored by way of the health of the Ocean, and our actions as residents of the Earth. Cousteau offered that, “When we think about our actions as teachers, students, tourists, parents, builders, farmers or name a profession, we must recognize all of our actions have environmental consequences…Because our health depends on the health of the planet, being aware of these connections can help us live responsibly” (NSTA Convention Program Itinerary, 2006). During his appearance, Cousteau impressed upon his audience the importance of understanding how the Ocean can help us to monitor the health of our Earth. Please note that I purposely use the term “Ocean” as opposed to “oceans” to emphasize the interconnectedness of this large body of water that covers over 70% of the Earth’s surface. I then began to reflect upon the fact that I did very little relative to incorporating ocean systems in our study of general chemistry. At this same conference, I was also introduced to the NOAA Teacher at Sea Program (TAS) and decided to apply during my next sabbatical leave in order to experience ongoing Ocean research with the hope of bringing this experience back into the classroom.
My goal as a TAS participant is to use this experience to help me explicitly incorporate Ocean related phenomena into the study of general chemistry topics such as density, conductivity, gas behavior, acid/base chemistry, solubility equilibrium, and kinetics. Additionally, I hope to develop new laboratory exercises that are Ocean related as well as to help students to realize the wealth of live NOAA data available to help them better understand the complexity of the Ocean. As a result I hope that students will gain a better understanding of “ocean chemistry” as well as to develop an appreciation of the interconnectedness among their actions, the health of our planet, and the health of the Ocean. Additionally, by actively participating in an ongoing ocean research project, I will develop a deeper understanding of the various career and research opportunities available for my students to pursue. I hope to convey to them the excitement of discovery as it relates to the Ocean thereby causing them to give serious consideration to following this line of study upon graduation.
A little bit about me…
I live with my wife of 38 years, Joan, in a rural community in central Massachusetts. Our daughter Jessica lives in Vermont and has provided us with three beautiful grandchildren. She currently leads their family’s home-school program and is expecting a new baby in June.
Our son Daniel is currently pursuing his Ph.D. program in Geology at the University of Delaware having completed his Master’s degree at this same institution. His studies focus on fluvial geomorphology.
Whenever possible my wife and I “escape to the Cape” to enjoy all that Outer Cape Cod has to offer. Our favorite activities include kayaking, freshwater, as well as saltwater fishing, dune riding, shell fishing, collecting mushrooms, collecting sea glass on long walks, and the peaceful views of the ocean beaches.
We also have a marine reef aquarium in our home, maintained steadfastly by my wife. The aquarium currently contains many varieties of soft corals that we are learning to propagate along with several types of reef “critters”.
During the winter months I enjoy downhill skiing and am a night-league NASTAR (NAtional STAndard Race) racer on a team known as the Sled Dogs. Our team’s motto, “strive for mediocrity” ensures that we focus on having fun and enjoying a winter’s evening of skiing at our local mountain.
In summary, I am eagerly looking forward to participating in the Teacher at Sea Program aboard the Oscar Dyson and all that this adventure has to offer! I will use this experience to help my students to better understand “ocean chemistry” as well as to develop an appreciation of the interconnectedness among their actions, the health of our planet, and the health of the Ocean.
Latitude: N 26° 03.476′
Longitude: W 080° 20.920′
Weather Data from home
Wind Speed: 7.8 knots (9 mph)
Wind Direction: East
Wave Height: 2 ft
Surface Water Temperature: 28.9°C (84°F)
Air Temperature: 30°C (86 °F)
Barometric Pressure: 1016 millibars ( 1 atm)
Science and Technology Log:
Below are the numbers that Johanna (my fellow Teacher at Sea) put together at the end of our mission.
We completed 44 hauls in our leg of the survey and caught approximately 118,474 pollock. All of those pollock weighed a collective 24,979.92 kg (= 25 tons)! Last year’s official total allowable catch (called a quota) for all commercial fishermen in Alaska was 1.17 million tons!
So, we only caught 25 tons/ 1,170,000 tons = 0.00002 = 0.002% of the yearly catch in our study.
The estimated population of pollock in the Bering Sea is 10 million tons (10,000,000 T). This means we caught only 0.00025% of the entire pollock population!
So, as you can see, in the big picture, our sampling for scientific analysis is quite TINY!
Continuing with more cool pollock data…
We identified 7,276 males and 7,145 females (and 2,219 were left unsexed)
We measured 16,640 pollock lengths on the Ichthystick!
Pollock lengths ranged from 9cm to 74cm
We measured 260 lengths of non-pollock species (mostly jellyfish, pacific herring, and pacific cod)
We collected 1,029 otoliths for analysis
After two full days of travel including a long red-eye flight across country, I am back in Ft Lauderdale, Florida. I had the most incredible experience as a NOAA Teacher at Sea on the Oscar Dyson! The trip was absolutely amazing! Here are some parting shots taken on my last day in Dutch Harbor, Alaska.
In closing, I would like to thank a few people. The NOAA Corps officers and deck crew are wonderful and do a great job running a tight ship. I would like to thank them all for keeping me safe, warm, dry, and well fed while out at sea. They all made me feel right at home.
The NOAA scientists Taina, Kresimir, Rick and Darin did a fabulous job patiently explaining the science occurring onboard and I appreciate them letting me become a part of the team! I loved immersing myself back in the practice of real scientific inquiry and research!
I would like to thank the NOAA Teacher at Sea program for allowing me to take part in this incredible research experience for teachers! Teachers and students in my district are very excited to hear about my experiences and I look forward to continuing to share with them about NOAA Teacher at Sea! Sign me up, and I’d be happy to “set sail” with NOAA again.
Finally, I would like to thank my readers. I truly enjoyed sharing my experiences with you and hope that, through my blog, you were able to experience a bit of the Bering Sea with me.
Latitude: 53°54’41” N
Longitude: 166°30’61” E
Ship speed: 0 knots (0 mph) In Captains Bay at Dutch Harbor during calibration.
Weather Data from the Bridge
Wind Speed: 17 knots (19.5 mph)
Wind Direction: 184°
Wave Height: 1-2 ft
Surface Water Temperature: 10.2°C (50.4°F)
Air Temperature: 12.5°C (54.5°F)
Barometric Pressure: 1005.9 millibars (0.99 atm)
Science and Technology Log:
Imagine a time when fish surveys could be done through remote sensing, thus eliminating the need to catch fish via trawling to verify fish school composition, length, weight, and age data. During our “Leg 3” of the Alaska Pollock Acoustic Midwater Trawl Survey, we caught, sorted, sexed, and measured 25 tons of pollock! While this amounts to only 0.002% of the entire pollock quota and 0.00025% of the pollock population, wouldn’t it be nice if we could determine the pollock population without killing as many fish?
Introducing the “Cam-Trawl,” a camera-in-net technology that NOAA scientists Kresimir and Rick are developing to eventually reduce, if not eliminate, the need to collect biological specimens to verify acoustic data. Cam-Trawl consists of a pair of calibrated cameras slightly offset so the result is a stereo-camera.
The importance of setting up a stereo-camera is so you can use the slightly different pictures taken at the same time from each camera to calculate length of the fish in the pictures. Eventually, a computer system might use complex algorithms to count and measure length of the fish that pass by the camera. If the kinks are worked out, the trawl net would be deployed with the codend open, allowing fish to enter the net and flow past the camera to have their picture taken before swimming out of the open end of the net. Some trawls would still require keeping the codend closed to determine gender ratios and weights for extrapolation calculations; however, the use of Cam-Trawl would significantly reduce the amount of pollock that see the fish lab of the Oscar Dyson. On this leg of the survey, the NOAA scientists installed the Cam-Trawl in a couple of different locations along the trawl net to determine where it might work best.
Below are some photos taken by Cam-Trawl of fish inside the AWT trawl net. Remember, there are two cameras installed as a stereo-camera that create two images that are taken at slightly different angles. In the photos below, I only picked one of the two images to show. In the video that follows, you can see how scientists use BOTH photos to calculate the lengths of the fish captured on camera.
Another NOAA innovation using stereo cameras is called “Trigger-Cam.” Trigger-Cam is installed into a crab pot to allow it to sit on the ocean floor. For this type of camera deployment, the NOAA scientists removed the crab pot net so they would not catch anything except pictures.
The real innovation in the Trigger-Cam is the ability to only take pictures when fish are present. Deep-water fish, in general, do not see red light. The Trigger-Cam leverages this by using a red LED to check for the presence of fish. If the fish come close enough, white LEDs are used as the flash to capture the image by the cameras.
The beauty of this system is that it uses existing fishing gear that crab fishermen are familiar with, so it will be easily deployable. Another stroke of brilliance is that the entire device will cost less than $3,000. This includes the two cameras, lights, onboard computer, nickel-metal hydride batteries, and a pressure housing capable of withstanding pressures of up to 50 atmospheres (500 meters) as tested on the Oscar Dyson! Here is a short animated PowerPoint that explains how Trigger-Cam works. Enjoy!
Here are a couple of picture captured by the Trigger-Cam during trials!
While these pictures were captured during tests in Dutch Harbor, they do provide proof-of-concept in this design. With a cheap, easily deployable and retrievable stereo-camera system that utilized fishing gear familiar to most deck hands, Trigger-Cams might contribute to NOAA’s future technology to passively survey fish populations.
A little fun at sea! We needed to do one last CTD (Conductivity, Temperature, Depth), and decided to lower the CTD over deep water down to 500 meters (1,640.42 ft)! Pressures increases 1 atmosphere for every 10 meters in depth. At 500 meters, the pressure is at 50 atmospheres!!! We wondered what would happen if… we took styrofoam cups down to that depth. We all decorated our cups and put them in a net mesh bag before they took the plunge. Here is a picture showing what 50 atmospheres of pressure will do to a styrofoam cup!
We missed the Summer Olympics while out on the Bering Sea. T-T We did get in the Olympic spirit and had a race or two. Here is a little video in the spirit of the Olympics…
All for now… We are back in Captains Bay, Dutch Harbor, but are calibrating the hydroacoustic equipment at anchor. Calibration involves suspending a solid copper sphere below the ship while the NOAA scientists check and fine-tune the different transducers. This process will take about 7 hours! We have been out at sea for 3 weeks, are currently surrounded by land, but must wait patiently to finish this last and very important scientific task. If the calibration is off, it could skew the data and result in an inaccurate population estimation and quotas that may not be sustainable! This Landlubber can’t wait to have his feet back on terra firma. The thought of swimming crossed my mind, but I think I’ll wait. Then we will see if I get Land Sickness from being out at sea for so long…
From those hauls, let me fill you in on some of the cool statistics:
We caught approximately 118,474 pollock and they weighed 24,979.92 kg (= 25 tons)!
COMPARE THAT TO:
Last year’s official total allowable catch (called a quota) for all commercial fishermen in Alaska was 1.17 million tons!
So, we only caught 25 tons/ 1,170,000 tons = 0.00002 = 0.002% of the yearly catch in our study.
COMPARE THAT to:
The estimated population of pollock in the Bering Sea is 10 million tons (10,000,000 T)!
This means we caught only 0.00025% of the entire pollock population!
So, as you can see, students, in the big picture, our sampling for scientific analysis is quite TINY!
Continuing with more cool pollock data…
We identified 7,276 males and 7,145 females (and 2,219 were left unsexed)
We measured 16,640 pollock lengths on the Ichthystick!
Pollock lengths ranged from 9cm to 74cm
We measured 260 lengths of non-pollock species (mostly jellyfish, pacific herring, and pacific cod)
We collected 1,029 otoliths for analysis
You will hear more about our results this fall— as well as the management decisions that will be made with this valuable data…
We have also had some exciting specimens on our bottom trawls. Remember, students, this simply means we drag the 83-112 net along the ocean floor. By sampling the bottom, we collect many non-pollock species that we would never see in the mid-water column.
Here are some of my favorites:
Next up, a very different sort: the Opilio Tanner Crab and the Bairdi Tanner Crab- both are known in the market as Snow Crabs!
Perhaps my favorite…
Followed by a slightly different type of lumpsucker!
These types of nets require a lot of hands to help sort the species as they come down the conveyor belt!
Onto… sea urchins!
And lastly, to those specimens you may have been waiting for if you are a fan of the “Deadliest Catch” TV show…
Interested in playing some online games from NOAA, students? Then visit the AFSC Activities Page here— I recommend “Age a Fish” and “Fish IQ Quiz” to get your started!
Lastly, students, as one final challenge, I would like you to take a look at the picture below and write back to me telling me a) what instrument/tool he is using and b) what it is used for:
Well, my time at sea has just about come to an end. This has been a wonderful experience, and I am very grateful to the NOAA science team (Taina, Darin, Kresimir, Rick, Anatoli, Kathy, and Dennis) for teaching me so much over these last three weeks. They have wonderful enthusiasm for their work and great dedication to doing great science! Not only do they work oh-so-very-hard, they are a really fun and personable group to be around! Many, many thanks to you all.
Thanks also go to my Teacher at Sea partner, Allan Phipps, for taking photos of me, brainstorming blog topics, helping out processing pollock during my shift, and other general good times. It was great to have another teacher on board to bounce ideas off of, and I learned a great deal about teaching in Southern Florida when we discussed our respective districts and schools.
I would also like to thank the NOAA officers and crew aboard the Oscar Dyson. I have really enjoyed learning about your roles on the ship over meals and snacks, as well as many chats on the bridge, deck, fish lab, lounge, and more. You are a very impressive and efficient group, with many fascinating stories to tell! I will look forward to monitoring the Dyson’s travels from Boston online, along with my students.
In the upcoming school year, students, you will learn how you can have a career working for NOAA, but you can start by reading about it here:
NOAA (the National Oceanic and Atmospheric Administration)
Alaskan Fisheries Science Center (the research branch of NOAA’s National Marine Fisheries Service dedicated to studying the North Pacific Ocean and East Bering Sea)
MACE (the Midwater Assessment and Conservation Engineering program- the NOAA group of scientists I worked with- based in Seattle)
Special thanks to our Commanding Officer (CO) Mark Boland and Chief Scientist Taina Honkalehto for supporting the Teacher at Sea program. I know I speak on behalf of many teachers when I say there are many, many ways I will be bringing your work into the classroom, and I hope, helping recruit some of the next generation of NOAA officers and scientists!
There are many pictures I could leave you with, but I decided to only choose two- one of a lovely afternoon on deck in the Bering Sea, and the other, of course, one more of me with a pollock head!
Latitude: 60°25’90” N
Longitude: 177°28’76” W
Ship speed: 3 knots (3.45 mph)
Weather Data from the Bridge
Wind Speed: 5 knots (5.75 mph)
Wind Direction: 45°
Wave Height: 2-4 ft with a 2 ft swell
Surface Water Temperature: 8.6°C (47.5 °F)
Air Temperature: 8°C (46.4 °F)
Barometric Pressure: 1019 millibars (1 atm)
Science and Technology Log:
In my last blog, we learned about how the scientists onboard the Oscar Dyson use some very sophisticated echo-location SONAR equipment to survey the Walleye pollock population.
Can the Walleye pollock hear the “pings” from the SONAR?
No. Unlike in the movies like “The Hunt for Red October” where submarines are using sound within the human audible range to “ping” their targets, the SONAR onboard the Oscar Dyson operates at frequencies higher than both the human and fish range of hearing. The frequency used for most data collection is 38 kHz. Human hearing ranges from 20 Hz to 20 kHz. Walleye pollock can hear up to 900 Hz. So, the pollock cannot hear the SONAR used to locate them…
Can the Walleye pollock hear the ship coming?
Normally, YES! Fish easily hear the low frequency noises emitted from ships.
If you are operating a research vessel trying to get an accurate estimate on how many fish are in a population, and those fish are avoiding you because they hear you coming, you will end up with artificially low populations estimates! The International Council for the Exploration of the Seas (ICES) established noise limits for research vessels that must be met in order to monitor fish populations without affecting their behavior. Fish normally react to a threat by diving, and that reduces their reflectivity or target strength, which reduces the total amount of backscatter and results in lower population estimates (see my last blog).
That is why NOAA has invested in noise-reducing technology for their fish survey fleet. The Oscar Dyson was the first of five ships build with noise-reducing technology. These high-tech ships have numerous strategies for reducing noise in the range that fish might hear.
There are two main sources of engine noise onboard a ship: machinery noise and propeller noise.
The best acoustic ship designs are going to address the following:
1) Address hydrodynamics with unique hull and propeller design.
2) Use inherently quiet equipment and choose rotating rather than reciprocating equipment.
3) Use dynamically stiff foundations for all equipment (vibration isolation).
4) Place noisier equipment toward the centerline of the ship.
5) Use double-hulls or place tanks (ballast and fuel tanks) outboard of the engine room to help isolate engine noise.
6) Use diesel electric motors (diesel motors operate as generators while electric motors run the driveshaft.
The U.S. Navy designed the Oscar Dyson’s hull and propeller for noise quieting. This propeller is designed to eliminate cavitation at or above the 11 knot survey speed. Not only does cavitation create noise, it can damage the propeller blades.
The Oscar Dyson’s hull has three distinguishing characteristics which increase its hydrodynamics and reduce noise by eliminating bubble sweep-down along the hull. The Oscar Dyson has no bulbous bow, has a raked keel line that descends bow to stern, and has streamlined hydrodynamic flow to the propeller.
To reduce a ship’s noise in the water, it is absolutely crucial to control vibration. The Oscar Dyson has four Caterpillar diesel gensets installed on double-stage vibration isolation systems. In fact, any reciprocating equipment onboard the Oscar Dyson is installed on a double-stage vibration isolation system using elastomeric marine-grade mounts.
Since the diesel engines are mounted on vibration isolation stages, it is necessary to also incorporate flexible couplings for all pipes and hoses connecting to these engines.
Any equipment with rotating parts is isolated with a single-stage vibration system. This includes equipment like the HVAC, the electric generators for the hydraulic pumps, and the fuel centrifuges that remove any water and/or particles from the fuel before the fuel is pumped to the diesel generators.
Low Noise Equipment:
The only equipment that does not use vibration isolation stages are the two Italian-made ASIRobicon electric motors that are mounted in line with the prop shaft. Both are hard-mounted directly to the ship because they are inherently low-noise motors. This is one of the benefits of using a diesel-electric hybrid system. The diesel motors can be isolated in the center of the ship, near the centerline and away from the stern. The electric motors can be located wherever they are needed since they are low noise.
Even the propeller shaft bearings are special water-lubricated bearings chosen because they have a low coefficient of friction and superior hydrodynamic performance at lower shaft speeds resulting in very quiet operation. They use water as a lubricant instead of oil so there is a zero risk of any oil pollution from the stern tube.
Acoustic Insulation and Damping Tiles:
The Oscar Dyson uses an acoustic insulation on the perimeter of the engine room and other noisy spaces. This insulation has a base material of either fiberglass or mineral wool. The middle layer is made of a high transmission loss material of limp mass such as leaded vinyl.
The Oscar Dyson also has 16 tons of damping tiles applied to the hull and bulkheads to reduce noise.
All of these noise-reducing efforts results in a fully ICES compliant research vessel able to survey fish and marine mammal populations with minimal disturbance. This will help set new baselines for population estimates nationally and internationally.
As you can see from the graph above, The Oscar Dyson is much quieter than the Miller Freeman, the ship that it is replacing. You can see the differences in the hull design from the picture below.
Next blog, I will write about new, cutting edge technology that might reduce the need for biological trawling to verify species.
Special thanks to Chief Marine Engineer Brent Jones for the tour of the engineering deck and engine room, and for the conversations explaining some of the technology that keeps the Oscar Dyson going.
I found out drills aboard ships are serious business! Unlike a fire drill at school where students meander across the street and wait for an “all clear” bell to send them meandering back to class, fire drills on a ship are carefully executed scenarios where all crew members perform very specific tasks. When out at sea, you cannot call the fire department to rescue you and put out a fire. The crew must be self-reliant and trained to address any emergency that arises. When we had a fire drill, I received permission from Commanding Officer Boland to leave my post (after I checked in) and watch as the crew moved through the ship to locate and isolate the fire. They even used a canister of simulated smoke to reduce visibility in the halls similar to what would be experienced in a real fire!
Late last night, we finished running our transects! Our last trawl on transect was a bottom trawl which brought up some crazy creatures! Here are a couple of photos of some of the critters we found.
Next blog will probably be my last from Alaska. T-T
NOAA Teacher at Sea Johanna Mendillo Aboard NOAA ship Oscar Dyson July 23 – August 10
Mission: Pollock research cruise Geographical area of the cruise: Bering Sea Date: Tuesday, August 7, 2012
Location Data from the Bridge: Latitude: 59○ 52 ’ N
Longitude: 177○ 17’ W
Ship speed: 8.0 knots ( 9.2 mph)
Weather Data from the Bridge:
Air temperature: 7.3○C (45.1ºF)
Surface water temperature: 8.4○C (47.1ºF)
Wind speed: 4 knots ( 4.6 mph)
Wind direction: 75○T
Barometric pressure: 1018 millibar (1 atm)
Science and Technology Log:
We are wrapping up our final few sampling transects. Now that you are practically fisheries biologists yourselves from reading this blog, students, we must return to the fundamental question— how do we FIND the pollock out here in the vast Bering Sea? The answer, in one word, is through ACOUSTICS!
Hydroacoustics is the study of and application of sound in water. Scientists on the Oscar Dyson use hydroacoustics to detect, assess, and monitor pollock populations in the Bering Sea.
Now, you may have heard of SONAR before and wonder how it connects to the field of hydroacoustics. Well, SONAR (SOund Navigation and Ranging) is an acoustic technique in which scientists send out sound waves and measure the “echo characteristics” of targets in the water when the sound waves bounce back— in this case, the targets are, of course, the pollock! It was originally developed in WWI to help locate enemy submarines! It has been used for scientific research for over 60 years.
(PLEASE NOTE: The words sonar, fishfinders, and echosounders can all be used interchangeably.)
On the Dyson, there is, not one, but a collection of five transducers on our echosounder, and they are set at five different frequencies. It is lowered beneath the ship’s hull on a retractable centerboard. The transducers are the actual part of the echosounder that act like antennae, both transmitting and receiving return signals.
The transducers transmit (send out) a “pulse” down through the water, at five different speeds ranging from 18-200kHz, which equals 18,000-200,000 sound waves a second!
When the pulse strikes the swim bladders inside the pollock, it gets reflected (bounced back) to the transducer and translated into an image.
First of all, what is a swim bladder? It is simply an organ in fish that helps them stay buoyant, and, in some cases, is important for their hearing.
Now, whydo the pulses bounce off the swim bladders, you ask? Well, they are filled mostly with air and thus act as a great medium for the sound waves to register and bounce back.
Think of it this way: water and air are two very different types of materials, and they have very different densities. The speed of sound always depends on the material through which the sound waves are traveling through. Because water and air have very different densities, there is a significant difference in the speed of sound through each material, and that difference in speed is what is easy for the sonar to pick up as a signal!
It is the same idea when sound waves are used to hit the bottom of the ocean to measure its depth- it is easy to read that signal because the change in material, from water to solid ground, produces a large change in the speed of the sound waves!
Interestingly, different types of fish have different shaped and sized swim bladders, and scientists have learned that they give off different return echos from sonar signals! These show up as slightly different shapes on the computer screen, and are called a fish’s “echo signature”. We know, however, that we will not encounter many fish other than pollock in this area of the Bering Sea, so we do not spend significant time studying the echo signatures on this cruise.
So, what happens when these signals return to the Dyson? They are then processed and transmitted onto the computer screens in the hydroacoutsics lab on board. This place is affectionately known as “the cave” because it has no windows, and it is, in fact, the place where I spend the majority of my time when I am not processing fish! Here it is:
We spend a lot of time monitoring those computer screens, and when we see lots of “specks” on the screen, we know we have encountered large numbers of pollock!
When the scientists have discussed and confirmed the presence of pollock, they then call up to the Bridge and announce we are “ready to go fishing” at a certain location and a certain depth range! Then, the scientists will head upstairs to the Bridge to work with the officers and deck crew to supervise the release, trawling, and retrieval of the net.
Now, in addition to the SONAR under the ship, there are sensors attached to the top of the net itself, transmitting back data. All of the return echos get transmitted to different screens on the bridge, so not only can you watch the fish in the water before they are caught, you can also “see” them on a different screen when they are in the net! As I told you in the last post, we will trawl for anywhere from 5-60 minutes, depending on how many fish are in the area!
In these last few days, we have crossed back and forth from the Russian Exclusive Economic Zone (EEZ) and the U.S. several times. There were some nice views of Eastern Russia before the clouds and fog rolled in!
In addition, we crossed over the International Date Line! It turns out that everyone on board gets a special certificate called the “Domain of the Golden Dragon” to mark this event. This is just one of a set of unofficial certificates that began with the U.S. Navy! If you spend enough time at sea, you can amass quite a collection- there are also certificates for crossing the Equator, Antarctic Circle, Arctic Circle, transiting the Panama Canal, going around the world, and more…
I will award a prize to the first person who writes back to tell me what does it mean when one goes from a “pollywog” to a “shellback”, in Navy-speak!
Here is a picture of me with the largest pollock I have seen so far- 70cm!
Lastly, on to some, perhaps, cuter and more cuddly creatures than pollock- pets! Here in the hydroacoustics lab, there is a wall dedicated to pictures of pets owned by the officers, crew, and scientists:
Clearly, this is a dog crowd! I did learn, however, that our Chief Scientist, Taina, has her cat (Luna) up there! Students, do you remember the name of my cat and, what do you think, should I leave a picture of her up here at sea?
Latitude: 60°55’68” N
Longitude: 179°34’49” E
Ship speed: 11 knots (12.7 mph)
Weather Data from the Bridge
Wind Speed: 10 knots (11.5 mph)
Wind Direction: 300°
Wave Height: 2-4 ft with a 4-6 ft swell
Surface Water Temperature: 8.7°C (47.6°F)
Air Temperature: 8°C (46.4°F)
Barometric Pressure: 1013 millibars (1 atm)
Science and Technology Log
Previously, we learned how the biological trawl data onboard the NOAA Research Vessel Oscar Dyson are collected and analyzed to help calculate biomass of the entire Bering Sea Walleye pollock population. Last blog, I mentioned that the scientific method for estimating the total pollock biomass is not complete without acoustics data, more specifically hydroacoustics! In fact, hydroacoustic data are the real key to estimating how many pollock are in the Bering Sea! That is why our mission is called the Alaskan Pollock Midwater ACOUSTIC-trawl Survey.
The Oscar Dyson is using hydroacoustics to collect data on the schools of fish in the water below us, but we do not know the composition of those schools. Hydroacoustics give us a proxy for the quantity of fish, but we need a closer look. The trawl data provide a sample from each aggregation of schools and allow the NOAA scientists that closer look. The trawl data explain the composition of each school by age, gender and species distribution. Basically, the trawl data verifies and validates the hydroacoustic data. The hydroacoustics data collected over the entire Bering Sea in systematic transects combined with the validating biological data from the numerous individual trawls give scientists a very good estimate for the entire Walleye pollock population in the Bering Sea.
So what is hydroacoustics and how does it work???
Hydroacoustics (“hydro” = water, “acoustics” = sound) is the field of study that deals with underwater sound. Remember, sound is a form of energy that travels in pressure waves. Sound travels roughly 4.3 times faster in water than in air (depending on temperature and salinity of the water). Here is a link with an interactive animation comparing the speed of sound in water, air, and steel! This change in speed will become very important later… keep reading!
Lower sound frequencies travel farther. This is how humpback whales can communicate over great distances with their whale songs! Click on whale songs to hear one!
Whales are not the only aquatic organisms to use sound! Much like dolphins use sound to echo-locate, people use technology to “see” under water using sound energy. We call this technology SONAR (Sound Navigation And Ranging).
On a typical recreational watercraft, this technology can be found in the form of a “fish-finder.”
In commercial fishing, this technology is used in much the same way, just on a larger scale. Here is an animation showing a commercial trawler using SONAR to locate fish.
The Oscar Dyson has a much more powerful, extremely sensitive, carefully calibrated, scientific version of what many people have on their bass boats. These are mounted on the pod, which is on the bottom of the centerboard, the lowest part of the ship. The Oscar Dyson has an entire suite of SONAR instrumentation including the five SIMRAD EK60 transducers located on the bottom of the centerboard that operate at different Khertz, the SIMRAD ME70 multibeam transducer located on the hull, and a pair of SIMRAD ITI transducers on the trailing edge of the centerboard (one pointed toward the starboard side, the other toward port).
This “fish-finder” technology works by emitting a sound wave at a particular frequency and waiting for the sound wave to bounce back (the echo) at the same frequency. The time between sending and receiving the sound wave determines how far away an object is, whether it be the bottom or fish. When the sound waves return from a school of fish, the strength of the returning echo helps determine the fish density (how many fish are there).
Another piece of the puzzle… how reflective an individual fish is to sound waves. This is called target strength. Each fish reflects sound energy sent from the transducers, but why? For fish, we rely on the swim bladder, the organ that fish use to stay buoyant in the water column. Since it is filled with air, it reflects sound very well. When the sound energy goes from one medium to another, there is a stronger reflection of that sound energy. The bigger the fish, the bigger the swim bladder; the bigger the swim bladder, the more sound is reflected and received by the transducer. We call this backscatter, or target strength, and use it to estimate the size of the fish we are detecting. This is why fish that have air-filled swim bladders show up nicely on hydroacoustic data while fish that lack swim bladders (like sharks), or that have oil or wax filled swim bladders (like Orange Roughy) have weak signals.
Target strength is how we determine how dense the fish are in a particular school. Scientists take the backscatter that we measure from the transducers and divide that by the target strength for an individual and that gives you the number of individuals that must be there to produce that amount of backscatter. 100 fish produce 100x more echo than a single fish. We extrapolate this information to all the area of the Bering Sea to estimate the pollock population.
So the goal is to measure the hydroacoustic density along each transect and extrapolate that data to represent the entire survey area between transects (the area not sampled because the Oscar Dyson can’t cover every square meter of the Bering Sea). When you combine the hydroacoustic data for all of the 30 transects (a total of ~5,000 nautical miles in an area of 100,000 square nautical miles) and the lengths collected in the biological trawl data, you can convert the length data into target strength data to create a distribution of target strengths and find the average target strength for the population. In doing so, you get a complete picture of the Walleye pollock population in the Bering Sea.
But there’s more!!! Scientists ALSO use hydroacoustic data when trawling to determine if they have caught a large enough sample size to collect fish length data to validate their target strength data. If you recall reading my first blog from sea that taught about the parts of the net, I wrote about and had a drawing of the “kite” on which the “turtle” was attached. The “turtle” is a SIMRAD FS70 trawl SONAR. It has a downward facing transponder that shows a digital “picture” of the size of the net opening. You can also see individual fish and/or schools of fish enter the net by watching this display. Since the scientists only need about 300 fish for a statistically significant sample, they watch this screen carefully so that they do not take more fish than they need. When the lead scientist thinks there are enough fish in the net, she gives the request to the Officer on Deck to “haul back.” Unlike commercial trawlers, a typical trawl on the Oscar Dyson only lasts 25 minutes. Sometimes, we are only officially fishing for 5 minutes if we pull through a large school.
What are the data telling us?
The Walleye pollock data suggest that the population is currently stable; however, there is some evidence of pollock in waters that have traditionally been north of their uppermost documented population range. Are warmer waters due to climate change to blame for this possible shift? Here is an interesting article that addresses this issue and raises several other trends regarding pollock population response to changes in food source and predation due to climate change. Click on the picture to open the article!
The economic and ecological implications of a shifting pollock population range are a bit unsettling. Fish do not know political boundaries. As the pollock population range possibly shifts north, more of that range will lie within Russian waters than in previous years. This may hurt the U.S. commercial fishing industry as they settle for less of a resource that was once abundant. Since quotas are set based on last year’s numbers, there is a time lag which may result in overfishing in U.S. waters that might lead to a collapse in the Alaskan Walleye pollock fishing industry. The U.S. has invested a tremendous amount of research into maintaining a sustainable pollock fishery. Other countries may be responding to a variety of factors in which sustainability is just one when they are managing pollock stocks and setting catch quotas. Since pollock is a trans-boundary stock, this could lead to greater uncertainty in management of the entire population if pollock increasingly colonize more northern Bering Sea waters as influenced by climate change.
Food for thought…
Next blog, we will learn about cutting edge technology that may eventually make hauling back fish and collecting biological fish data on board the acoustic survey missions obsolete.
It’s tomorrow, TODAY! This morning at 6am Alaska Time, we crossed the International Date Line (IDL). The IDL is at 180° longitude. General Vessel Assistant Brian Kibler and I went out to the bow of the ship so we would be the first onboard to cross the line!
Over the next two days, our transects take us back and forth over the IDL 3 more times. Fortunately, onboard our Oscar Dyson time warp machine we simply observe the Alaska Time Zone (the time zone from our port of call). With everyone onboard operating different shifts, and with 24/7 operations, it would be quite confusing if we kept changing our clocks to observe the local time zone.
Mariners who cross the IDL when at sea are inducted into the “Order of the Golden Dragon” and receive a certificate with the details of this momentous crossing. There are several other notorious crossing that receive special recognition. They are:
▪ The Order of the Blue Nose for sailors who have crossed the Arctic Circle.
▪ The Order of the Red Nose for sailors who have crossed the Antarctic Circle.
▪ The Order of the Ditch for sailors who have passed through the Panama Canal.
▪ The Order of the Rock for sailors who have transited the Strait of Gibraltar.
▪ The Safari to Suez for sailors who have passed through the Suez Canal.
▪ The Order of the Shellback for sailors who have crossed the Equator.
▪ The Golden Shellback for sailors who have crossed the point where the Equator crosses the International Date Line.
▪ The Emerald Shellback or Royal Diamond Shellback for sailors who cross at 0 degrees off the coast of West Africa (where the Equator crosses the Prime Meridian)
▪ The Realm of the Czars for sailors who crossed into the Black Sea.
▪ The Order of Magellan for sailors who circumnavigated the earth.
▪ The Order of the Lakes for sailors who have sailed on all five Great Lakes.
NOAA Teacher at Sea
Aboard NOAA ship Oscar Dyson July 23 – August 10
Mission: Pollock research cruise
Geographical area of the cruise: Bering Sea
Date: Sunday, August 5, 2012
Latitude: 61º 10′ N
Longitude: 179º 28’W
Ship speed: 4.3 knots ( 4.9 mph)
Weather Data from the Bridge
Air temperature: 11.1ºC (52ºF)
Surface water temperature: 8.1ºC (46.6ºF)
Wind speed: 5.4 knots ( 6.2 mph)
Wind direction: 270ºT
Barometric pressure: 1013 millibar ( 1.0 atm)
Science and Technology Log:
So far, you have learned a lot about the pollock research we conduct on board. You have learned:
How to age fish (with otoliths)
How to measure fish (with the Ichthystick)
How to identify fish gender (with your eyes!)
Now, we are going to backtrack a bit to the two big-picture topics that remain:
How do we CATCH the pollock (hint hint, that is today’s topics… NETS!)
How do we even find pollock in the Bering Sea (that is the next blog’s focus: acoustics!)
So, to begin, there are several types of nets we are carrying on board. Remember, when a net is dragged behind a ship in the water it is called trawling, and the net can be considered a trawl. The most-used is the Aleutian Wing Trawl, or AWT, which we use to sample the mid-water column (called a midwater trawl). We are also using a net called the 83-112, which is designed to be dragged along the ocean floor as a bottom trawl, but we are testing it for midwater fishing instead. In fact, sometimes during my shift we do one AWT trawl, and immediately turn around and go over the same area again with the 83-112 to see differences in the fish sizes we catch!
If the 83-112, which is a smaller net, proves to be adequate for midwater sampling, NOAA hopes it can be used off of smaller vessels for more frequent sampling, especially in the years the NOAA does not conduct the AWT (NOAA currently does AWT surveys biennially).
Now, for each type of net, there is some new vocabulary you should know:
The codend is the bottom of the net. A closed codend keeps the fish inside the net and an open cod end allows them to swim through. It may seem odd, but yes, sometimes scientists do keep the codend open on purpose! They do this with a camera attached to the net, and they simply record the numbers of fish traveling through a certain area in a certain time period, without actually collecting them! Here on the Dyson, the NOAA team is testing that exact type of technology with a new underwater camera called the Cam-Trawl, and you will learn about it in a later post.
The headrope is the top of the opening of the net.
The footrope is the bottom of the opening of the net.
(The 83-112 is called such because it has an 83 ft headrope and an 112 ft footrope.)
The trawl doors are in front of the headrope and help keep the net open. Water pressure against the trawl doors pushes them apart in the water column during both setting of the net and while trawling, and this helps spread out the net so it maintains a wide mouth opening to catch fish.
There are floats on the top of the net and there can be weights on the bottom of the net to also help keep it open.
Lastly, the mesh size of the net changes: the size at the mouth of the net is 3 meters (128in.), and it decreases to 64in., 32in., 16in.., 8in., etc. until it is only ½ inch by the time you are holding the codend!
Here is a diagram to put it all together:
If you think about the opening of the net in terms of school buses, it will help! It turns out that the AWT’s opening height, from footrope to headrope, is 25m, which is 2 school buses high! The AWT’s opening width, is 40m across, about 3.5 school buses across! Now, you can see why positioning and maneuvering the net takes so much care– and how we can catch a lot of pollock!
Now, when the scientists decide it is “time to go fishing” (from acoustic data, which will be the topic of the next blog) they call the officers up on the Bridge, who orient the ship into its optimal position and slow it down for the upcoming trawl. Meanwhile, the deck crew is preparing the net. The scientists then move from their lab up to the Bridge to join the officers– and they work together to monitor the location and size of the nearby pollock population and oversee the release and retrieval of the net.
Along the headrope, there are sensors to relay information to the Bridge, such as:
The depth of the net
The shape of the net
If the net is tangled or not
How far the net is off the bottom and
If fish are actually swimming into the net!
The fish and the net are tracked on this array of computer screens. As the officers and scientists view them, adjustments to the net and its depth can be made:
The start of the trawl is called “EQ” – Equilibrium and the end of the trawl is called “HB” – haul back. The net can be in the water anywhere from 5-60 minutes, depending on how many fish are in the area.
Now, sometimes an AWT catches so many fish that there are simply too many for us to measure and process in a timely fashion, so it is deemed a “splitter”! In a splitter, there’s an extra step between hauling in the net from the ocean and emptying it to be sorted and processed. The codend of the AWT is opened over a splitting crate, and half of the pollock go into a new net (that we will keep and sort through) and the rest of the pollock are returned to the water.
Let’s continue our tour aboard the Oscar Dyson! Follow me, back to the bridge, where the OOD (Officer on Duty) is at the helm. As you already know, the first thing you notice on the bridge is the vast collection of computer screens at their disposal, ready to track information of all kinds. You will learn more about these in an upcoming blog.
In addition to these high-tech instruments, I was very happy to see good old-fashioned plotting on a nautical chart. In class, students, you will have a special project where you get to track the changing position of the Oscar Dyson!
Here is a sample of the hour-by-hour plotting, done by divider, triangle, and pencil:
I will end here with a sea specimen VERY different from pollock, but always a fan favorite— jellyfish! Interestingly, there are a large number of jellyfish in the Bering Sea- something I never would have assumed. The one that we catch in almost every net is the Northern Sea Nettle (Chrysaora melanaster). In one net, we collected 22 individuals!
When we collect non-pollock species such as these, we count, weigh, and record them in the computerized database and then release them back into the ocean. Here they are coming down the conveyor belt after the net has been emptied:
The so-called bell, or the medusa, can be quite large- some are the diameter of large dinner plates (45cm)! Their tentacles can extend to over 3m in length. They consume mostly zooplankton, small fish (including juvenile pollock), and other jellies. How so, exactly? Well, when the tentacles touch prey, the nematocysts (stinging cells) paralyze it. From there, the prey is moved to the mouth-arms and finally to the mouth, where it’s digested.
This same mechanism is used by sea nettle when it encounters danger like a large predator. It stings the predator with its nematocysts and injects its toxins into its flesh. In the case of smaller predators, this venom is strong enough to cause death. In larger animals, however, it usually produces a paralyzing effect, which gives the sea nettle enough time to escape.
Now in the case of me handling them… and other humans…their sting is considered moderate to severe. In most cases, it produces a rash, and in some cases, an allergic reaction. However, we wear gloves on board and none of the scientists have ever had an issue holding them. In fact, they offered to put one on my head and take a picture… but I declined! If a few students email me, begging for such a picture, maybe I will oblige…
NOAA Teacher at Sea Johanna Mendillo Aboard NOAA Ship Oscar Dyson July 23 – August 10, 2012
Mission: Pollock Survey Geographical area of the cruise: Bering Sea
Date: Saturday, August 4, 2012
Location Data from the Bridge: Latitude: 62○ 20’ N
Longitude: 179○ 38’ W
Ship speed: 0.8 knots (0.9 mph)
Weather Data from the Bridge:
Air temperature: 7.1○C (44.8ºF)
Surface water temperature: 8.3○C (46.9ºF)
Wind speed: 22.7 knots (26.1 mph)
Wind direction: 205○T
Barometric pressure: 1009 millibar (1.0 atm)
Science and Technology Log:
Out of the 30,000+ species of fish on earth, I would now like to introduce you to the fish we follow morning, noon, and night: pollock.
It is time for some fish biology 101! The scientific name for pollock, also called walleye pollock, is Theragra chalcogramma. This is a different species from its East Coast relative, Atlantic Pollock. They are in the same family as cod and haddock.
AGE & SIZE: Pollock are a fast-growing species that typically live to approximately 12yrs, but some live longer. They are torpedo shaped (long, narrow, and with a streamlined body) and have speckled coloring that help them camouflage with the seafloor to avoid predators. They generally range from 10-60cm in size; we have been collecting pollock generally in the 20-40cm range so far on this cruise. Here I am holding one of the larger specimens I have seen so far:
WHERE THEY LIVE: Younger pollock live in the mid-water region of the ocean; older pollock (age 5 and up) typically dwell near the ocean floor. In order to sample both of these groups, we conduct trawls throughout the water column so we can get representative biological information from all habitats.
PREDATORS & PREY:
Juvenile pollock eat a type of zooplankton called euphausids, otherwise known as krill, copepods, and small fish. Older pollock feed on other fish…. including juvenile pollock, making them a cannibalistic species! Pollock play an integral role in the Bering Sea food web and you will help construct that web back at school!
REPRODUCTION: Pollock are able to reproduce by the age of 3 or 4. In our work, we have to determine the sex of each fish by slicing it open because no reproductive organs are visible on the outside! So, in addition to seeing the insides of many, many fish heads, I have now seen many, many fish gonads. Here is a poster we use in the lab to learn how to identify the ovaries and testes at five different developmental stages (immature, developing, pre-spawning, spawning, and spent).
So, how do you tell, exactly? On the females, we go by the following guidelines:
Immature female pollock contain small ovaries tucked inside the body cavity, the ovary looks transparent, and there are no eggs visible.
Developing females have more visible and pink-ish ovaries, generally transparent to opaque.
Pre-spawning females contain large bright orange ovaries and eggs are easily discernible inside them
Spawning females have large ovaries bursting with hydrated eggs (the fish has absorbed large amounts of water at this point), so the eggs look translucent or even transparent!
Spent females have empty flaccid ovaries.
It can sometimes be difficult to identify a female maturity stage by this simple visual scale (this is called macroscopic inspection), due to subjective interpretations of color, ovary size, and visibility of eggs, so fisheries biologists can also collect cell samples to look at gamete stages under the microscope (this is called histological analysis). For example, a female’s ovaries can be slightly different colors based on her diet. We are not collecting those types of samples on this cruise, however, but those are often collected during wintertime pollock cruises in the Gulf of Alaska.
Regardless of the method used, determining the ratio of different maturity stages in the female pollock population has very important implications for how scientists calculate spawning biomass estimates, which in turn, are entered into statistical models to determine age class structures, overall population sizes, and, finally, catch quotas for the fishing industry.
On the males, we go by the following guidelines:
Immature male pollock have threadlike testes with a transparent membrane (that can be very hard to see).
Developing males have testes which look like smooth, uniformly textured ribbons.
Pre-spawning male testes appear as larger thicker ribbons.
Spawning males exhibit large testes that extrude sperm when pressed.
Spent males have large, flaccid, bloodshot, and watery testes.
As for how they reproduce, pollock, like most fish, do external fertilization, which means they release eggs and sperm into the water, where they come together and fertilize. For pollock in the northern Bering Sea, this tends to happen in the winter, from January-early April. It appears that sub-populations in other areas of the Bering Sea and the Gulf of Alaska spawn during shorter time windows throughout the late winter and early spring.
Fish gather in large groups to spawn, and an individual female pollock can release anywhere from 10,000s – 100,000s of eggs in a single season! They could also be released at one time or in several batches, called batch spawning. Interestingly, if conditions are not optimal, such as low water temperatures or poor nutrition, females can reabsorb eggs, in a process called atresia.
After spawning and fertilization, the resulting larvae grow into juveniles, the juveniles grow into adults, and the process starts anew! Overall, scientists still have much to learn about the timing and mechanisms behind the pollock reproductive process— and I have enjoyed learning about it from the NOAA team!
First, the answer was… 75 dozen eggs! Those were some pretty close guesses, good job!
Let’s continue our tour aboard the Oscar Dyson! Now, as you can imagine, safety and training are very important parts of life at sea. I feel very confident in the crew and officers’ careful preparedness. Each week, we conduct safety drills. There are three types: man overboard, fire, and abandon ship. For each drill, each member of the ship has to report to a certain station to check in. In addition, you may be assigned to bring something, such as a radio, first aid kit, etc.
The drill I was most interested in was abandon ship, because not only do you carry your emergency survival (also known as an immersion) suit with you, but sometimes you practice putting it on! I had seen many pictures of other Teachers at Sea wearing them and wanted the chance to try it on myself!
So, without further ado, here are Allan and I in our suits:
What do you think, do we look like Gumby???
So, how exactly does it work? Well, it is a special type of waterproof dry suit that protects the wearer from hypothermia in cold water after abandoning a sinking or capsized vessel. It is made of stretchable flame retardant neoprene, and contains insulated gloves, reflective tape, whistle, and a face shield for spray protection. The neoprene material is a synthetic rubber with closed-cell foam, which contains many tiny air bubbles, making the suit sufficiently buoyant to also be a personal flotation device.
There are various types of immersion suits. Some contain:
An emergency strobe light beacon with a water-activated battery
An inflatable air bladder to lift the wearer’s head up out of the water
An emergency radio beacon locator
A “buddy line” to attach to others’ suits to keep a group together
Sea dye markers to increase visibility in water
We keep them in our rooms and there are many others placed throughout the ship in case we are not able to return to our rooms in a real emergency.
I hope that gives you a good feel for life onboard here in week two. Please post a comment below, students, with any questions at all.
Latitude: 61°12’61” N
Longitude: 178°27’175″ W
Ship speed: 11.6 knots (13.3 mph)
Weather Data from the Bridge
Wind Speed: 11 knots (12.7 mph)
Wind Direction: 193°
Wave Height: 2-4 ft (0.6 – 1.2 m)
Surface Water Temperature: 8.3°C ( 47°F)
Air Temperature: 8.5°C (47.3°F)
Barometric Pressure: 999.98 millibars (0.99 atm)
Science and Technology Log
At the end of last blog, I asked the question, “What do you do with all these fish data?”
The easy answer is… try and determine how many fish are in the sea. That way, you can establish sustainable fishing limits. But there is a little more to the story…
Historically, all fisheries data were based on length. It is a lot easier to measure the length of a fish than to accurately determine its weight on a ship at sea. To accurately measure weight on a ship, you have to have special scales that account for the changes in weight due to the up and down motion of the ship. Similar to riding a roller coaster, at the crest of a wave (or top of a hill on a roller coaster), the fish would appear to weigh less as it experiences less gravitational force. At the trough of a wave (or bottom of a hill on a roller coaster), the fish would experience more gravitational force and appear to weigh more. Motion compensating scales are a more recent invention, so, historically, it was easier to just measure lengths.
For fisheries management purposes, however, you want to be able to determine the mass of each fish in your sample and inevitably the biomass of the entire fishery in order to decide on quotas to determine a sustainable fishing rate. So, you need to be able to use length data to estimate mass. Here is where science and math come to the rescue! By taking a random sample that is large enough to be statistically significant, and by using the actual length and weight data from that sample, you can create a model to represent the entire population. In doing so, you can use the model for estimating weights even if all you know is the lengths of the fish that you sample. Then you can extrapolate that data (using the analysis of your acoustic data – more on this later) to determine the entire size of the pollock biomass in the Bering Sea.
How do they do that? First, you analyze and plot the actual lengths vs. weights of your random sample and your result is a scatter-plot diagram that appears to be an exponential curve.
Then you create a linear model by log-transforming the data. This gives you a straight line.
Next, you back-transform the data into linear space (instead of log space) and you will have created a model for estimating weight of pollock if all you know are the lengths of the fish. This is close to a cubic expansion which makes sense because you are going from a one-dimensional measurement (length) to a 3-dimensional measurement (volume).
Scientists can now use this line to predict weights from all of their fish samples and then extrapolate to determine the entire biomass of Walleye pollock population in the Bering Sea (when combined with acoustic data… coming up in the next blog!) when the majority of the data collected is only fish lengths.
Another interesting question… How does length change with age? Fish get bigger as they get older, all the way until they die, which is different from mammals and birds. However, some individual fish grow faster than others, so the relationship between age and length gets a little complicated. How do you determine the age distribution of an entire population when all you are collecting are lengths?
Just like weight, you can determine the age from a subset of fish and apply your results to the rest. This works great with young fish that are one year old. The problem is… once you get beyond a one-year-old fish, using lengths alone to determine age becomes a little sketchy. Different fish may have had a better life than others (environmental/ecological effects) and had plenty to eat, great growing conditions, etc and be big for their age relative to the rest of the population. Some may have had less to eat and/or unfavorable conditions such as high parasite loads leading them to be smaller… There are also other things to consider such as genetics that affect length and growth rate of individuals. Here is where the collection of otoliths becomes important. By collecting the otoliths with the lengths, weights, and gender data, the scientists can look at the age distributions within the population. The graph below shows that if a pollock is 15 cm long, it is clearly a 1 year old fish. If a pollock is 30 cm long, it might be a 2 year old, a 3 year old, or a 4 year old fish, but about 90% of fish at this length will be 3 years old. If a fish is 55 cm long, it could be anywhere from 6 to 10+ years old!
Collection of otoliths is the only way to accurately determine the age of the fish in the random sample and be able to extrapolate that data to determine the estimated age of all the pollock in the fishery. Here is a photo comparing otolith size of Walleye pollock with their lengths.
If we wanted to find out exactly how old each of these fish were, we would need to break the otoliths in half to look at a cross section. Below is what a prepared otolith looks like (courtesy of Alaska Fisheries Science Center). You can try counting rings yourself at their interactive otolith activity found here.
All of these data go into a much more complicated model (including the acoustic-trawl survey walleye pollock population estimates) to accurately estimate the total size of the fishery and set the quotas for the pollock fishing industry so that the fishery is maintained in a sustainable manner.
Next blog, we will learn about how the various ways acoustic data fit into this equation to create the pollock fishery model!
Ok, so here is a long overdue look at the NOAA Ship Oscar Dyson that I am calling home for three weeks. I was pleasantly surprised when I saw my state room. It is bigger than I thought it would be and came with its own bathroom. I was also pleasantly surprised to learn I would be sharing my state room with Kresimir Williams, one of the NOAA scientists and an old college friend of mine! Here is a picture of our room.
The room has a set of bunk beds. Thankfully, my bed is on the bottom. I do not know how I would have gotten in and out of bed in the rough seas we had over the last couple of days. If I do fall out of bed, at least I will not have far to fall. Last year, the ship rocked so hard in rough seas that one of the scientists fell head first out of the top bunk! The room also had two lockers that serve as closets, a desk and chair, and our immersion suits (the red gumby suits). The bathroom is small and the shower is tiny! Notice the handles on the wall. These are really handy when trying to shower in rough seas!
Next, we have the Galley or Mess Hall. This is where we have all of our meals prepared by Tim and Adam. Notice that all of the chairs have tennis balls on the legs and that each chair has a bungee cord securing it to the floor! There are also bungee cords over the plates and bowls. Everything has to be secured for rough seas.
The Mess Hall also has a salad bar, cereal bar, sandwich fixings, soup, snacks like cookies, and ice cream available 24 hours a day. No one on board is going hungry. The food has been excellent! We have had steaks, ribs, hamburgers and fish that Tim has grilled right out on deck. Here is a picture of my “surf and turf” with a double-baked potato.
Most of my work here on board (other than processing fish) has been in the acoustics lab, also known as “The Cave” since it has no windows. This is where the NOAA scientists are collecting acoustic data on the schools of fish and comparing the acoustic data with the biological samples we process in the fish lab.
I also spend some time up on the Bridge. From the Bridge, you can see 10 to 12+ nautical miles on a clear day. This morning, we saw a couple of humpback whales blowing (surfacing to breathe) about 1/4 mile off our starboard side! A couple of days ago (before the weather turned foul), we spotted an American trawler.
Today, we got close enough to see the Russian coastline! Here is a picture of a small tanker ship with the Russian coastline in the background!
Here are some pictures of the helm and some of the technology we have onboard to help navigate the ship.
I have also spent some time in the lounge. This is where you can go to watch movies, play darts (yea, right! on a ship in rough weather???), or just relax. The couch and chairs are so very comfy!
When you have 30 people on board and in close quarters, you better have a place to do laundry! Here is a picture of our very own laundromat.
All for now. Next time, I will share more about life at sea!
NOAA Teacher at Sea Johanna Mendillo Aboard NOAA Ship Oscar Dyson July 23 – August 10, 2012
Mission: Pollock Survey Geographical area of the cruise: Bering Sea Date: Wednesday, August 1, 2012
Location Data from the Bridge: Latitude: 62○ 18’ N
Longitude: 178○ 51’ W
Ship speed: 2.5 knots (2.9 mph)
Weather Data from the Bridge:
Air temperature: 9.5○C (49.1ºF)
Surface water temperature: 8.5○C (47.3ºF)
Wind speed: 9.1 knots (10.5 mph)
Wind direction: 270○T
Barometric pressure: 1001 millibar (0.99 atm)
Science and Technology Log:
In the last few days, we have crossed into the Russian Exclusive Economic Zone, sampled, and are now back on the U.S. side! Unfortunately, students, there was no way for my passport to get stamped. There was no formal ceremony, and we will cross back and forth many times in the next two weeks as we do our science transects, collecting Pollock, but the science team took a moment to celebrate— and I snapped a quick picture of the computer screen.
I would now like to introduce you to one of the most simple and valuable tools we use on board to measure a sample of Pollock- the Ichthystick.
First, some background. Each day we “go fishing” 2-4 times with our mid-water and bottom trawls. “Trawling” simply means dragging a large net through the water to collect fish (and you will learn more about the different types of nets we use quite soon). After the trawl, we bring the net back on board and see what we have caught!
There are many types of data we collect from each catch- first and foremost, the total weight of the catch and the numbers and masses of any species we catch in addition to pollock. So far, we have collected salmon, herring, cod, lumpsuckers, rock sole, arrowtooth flounder, Greenland turbot, and jellyfish on my shifts! Our focus, though, of course, is pollock. For pollock-specific data, we keep a sub-sample of the catch, usually 300-500 fish, for further analysis, and we release the rest back into the ocean.
From this sub-sample, I help the scientists collect gender and length data. As I mentioned in my last post, we also collect otoliths from the sub-samples so that the age structure of the population can be studied back in Seattle. The most straightforward and obvious data, though, is simply measuring the length of the fish, which takes us back to the wonderful contraption known as the Ichthystick!
Now, scientists cannot determines the age of a pollock simply from measuring its length- there are many factors that determine how fast a fish can grow, such as access to food, space, its overall health, environmental conditions, etc. But, by collecting length data and combining it with age data from otoliths, scientists can begin to see the length ranges at each age class and the overall “big picture” for the population emerges.
And again, once the age structure and population size of pollock in the Bering Sea are determined for a certain year, management decisions can be made, commercial fish quotas are set for the upcoming fishing season, and there will still be a suitable population of fish left in the ocean to reproduce and keep the stocks at sustainable levels for upcoming years.
So, it clearly does not make much sense to measure pollock with a ruler, paper, and pencil. To measure hundreds of fish at a time, the NOAA team has developed a simple yet ingenious measuring tool, powered by magnets, and transmitted electronically back to their computers for easy analysis- the Ichthystick!
The Ichthystick may simply look like a large ruler, but it consists of a sensor and electronic processing board mounted in a protective (& waterproof!) container. Inside, the sensor processes, formats and transmits the measurement values of each fish to an external computer that collects and stores the data.
Interestingly, the board works with magnets and makes use of the property of magnetostriction.
With magnetostriction, magnetic materials change shape when exposed to a magnetic field. Magnetostrictive sensors can use this property to measure distances by calculating the “time of flight” for a sonic pulse generated in a magnetic filament when a measurement magnet is placed close to the sensor. Here, in the picture, I am placing the fish along the sensor and holding the measurement magnet in my right hand.
To determine the distance to the measurement magnet, the elapsed time between when I touch the magnet to the board to generate the ultrasonic pulse and when the pulse is detected by the sensor is recorded– and that time is converted to a distance (using the speed of sound in that material), which is equal to the fish’s length!
Now, the “measurement magnet” is referred to as the “stylus”, and it is a little white plastic piece, the size of a magic marker cap, which contains the magnet embedded into the bottom. You simply strap the stylus onto your index finger with velcro (so that the north pole of the magnet is facing down toward the sensor) and are ready to begin measuring! The magnet inside is a small neodymium magnet, chosen because it has a very strong magnetic field. Each time a measurement is recorded, a chime sounds, and I know I can go on to measuring my next fish! At this point, I have measured a few thousand fish!
Let’s continue our tour aboard the Oscar Dyson! I think it is fair to say that scientific research makes one hungry! I have enjoyed meeting Tim and Adam, the stewards (chefs) onboard the Dyson, devouring their delicious meals, and spending time talking with the officers and crew in the galley (kitchen) and mess (dining hall). As you can see from my picture, the first thing you notice are the tennis balls on the bottoms of the chairs! Why do you think they are there?
As in most things related to ship design, planning for rough seas is paramount! So, in addition to tennis balls, which stop the chairs from sliding around, there are bungee cords that attach the chairs to the floor. The dishes are also strapped down and most items are in boxes, bins, or behind closed doors. But do not let that fool you— there is a LOT of food in there! I have enjoyed many a midnight snack- fruit, yogurt, ice cream bars, cereal bars, cookies, and soup to name just a few. In addition, there is a salad bar and a selection of leftover dinner items available to reheat each night. Since I am on the 4pm-4am shift, I have been missing breakfast, and I have been told I must have at least one hot cooked-to-order meal before I depart!
I was a little surprised to see a mini-Starbucks on board too! It is quite a setup, complete with pictures and directions on how to make each concoction:
Dennis, one of the Survey Technicians who works on the overnight shift with me, promised to make me a hazelnut latte if I could correctly predict the number of pollock in a trawl, Price-Is-Right style. I finally won a few nights ago….
Interestingly, there are no mechanisms in place to help the stewards cook in rough seas, but Adam assured me that he has never had a dinner for thirty slide off the grill and onto the floor! Adam has been working in the NOAA fleet for over 10 yrs., including 7 yrs on the Miller Freeman, the precursor to the Oscar Dyson. He has been onboard the Dyson for almost a year. Tim has just joined the Dyson on this cruise and was previously in our home state— aboard the Delaware out of Woods Hole, Massachusetts! Before joining NOAA, he worked on several supply ships that sailed across the world. Each has been quite friendly and helpful as I learn to navigate my way around both the ship and my new schedule. One of our frequent conversations is menu planning and the all-important-dessert on the schedule for each night. So far, I have enjoyed apple cobbler, pineapple upside down cake, snickers cake, carrot cake, brownie sundaes, oatmeal raisin cookies, and… Boston cream pie!
One last Q: How many dozens of eggs do you think Tim and Adam will go through on our 19-day cruise with 30 people on board? Write your guess in the comment section and I will announce the answer in my next post…
Latitude: N 61°39’29”
Longitude: W 117°55’90”
Ship speed: 11.7 knots (13.5mph)
Weather Data from the Bridge
Wind Speed: 26 knots (30mph)
Wind Direction: 044°
Wave Height: 4 meters (12 ft)
Surface Water Temperature: 8.2°C ( 46.8°F)
Air Temperature: 7.4°C (45°F)
Barometric Pressure: 994 millibar (0.98 atm)
Science and Technology Log:
Last blog, we learned about the different trawl nets and how the NOAA scientists are comparing those nets while conducting the mid-water acoustic pollock survey. We left off with the fish being released from the codend onto the lift table and entering the fish lab. Here is where the biological data is collected.
The fish lab is where the catch is sorted, weighed, counted, measured, sexed, and biological samples such as the otoliths, or earbones, are taken (more about otoliths later in this post). First, the fish come down a conveyor belt where they are sorted by species (see video above). Typically, the most numerous species (in our case pollock) stay on the conveyor and any other species (jellyfish and/or herring, but sometimes a salmon or two, or maybe even something unique like a lumpsucker!), are put into separate baskets to weigh and include in the inventory count. In the commercial fishing industry, these species would be considered bycatch, but since we are doing an inventory survey, we document all species caught. Here are some pictures of others species caught and included in the midwater survey.
The goal of each trawl is to randomly select a sample of 300 pollock to measure as a good representation of the population (remember your statistics! Larger sample sizes will give you a better approximation of the real population). If more than 300 pollock are caught, the remainder are weighed in baskets and quickly sent back to sea. All of the catch is weighed so the scientists can use the length and gender data taken from the sample to extrapolate for the entire catch. This data is combined with the acoustics data to estimate the size of the entire fishery (more on acoustic data in a future post). Weights are entered via touch screen into a program (Catch Logger for Acoustic Midwater Surveys – CLAMS) developed by the NOAA scientists onboard.
The 300 pollock are sexed to determine the male/female ratio of this randomly selected portion of the population. Gender is determined by making an incision along the ventral side from posterior to anterior beginning near the vent. This exposes the internal organs so that either ovaries or testes can be seen. Sometimes determining gender is tricky since the gonads look very different as fish pass through pre-spawning, spawning, or post-spawning stages. When we determine gender, the fish are put into two separate hoppers, the one for females is labeled “Sheilas” and the hopper for males is labeled “Blokes.”
We use an Ichthystick to then measure the males and females separately to collect length data for this randomly selected sample. Designed by NOAA Scientists Rick and Kresimir, the Ichthystick very quickly measures lengths by using a magnet placed at the fork of the fish’s tail (when measuring fork-length). This sends a signal to the computer to record the individual fish’s length data immediately into a spreadsheet and the software creates a population length distribution histogram in real-time as you enter data.
A randomly selected subset of 40 pollock get individually weighed, length measured, sexed, evaluated for gonadal maturity and have the otoliths removed. Otoliths (oto = ear, lithos = bone) are calciferous bony structures in the fish’s inner ear. These are used to determine age when examined via cross-section under a dissecting scope. The number of rings corresponds to the age of the pollock, similar to rings seen in trees. The otoliths are taken by holding the fish at the operculum and making an incision across the top of the head to expose the brain and utricle of the inner ear. The otolith is found inside the utricle. Forceps are used to extract the otoliths, which are then washed and put in individual bar-coded vials with glycerol-thymol solution to preserve them for analysis back at the Alaska Fisheries Science Center.
Watch this short video to see what the entire process of data collection looks like.
So… why collect all of this data? How is this data analyzed and used? Stay tuned to my next blog!
Well, I can officially say… the honeymoon is over. The Bering Sea had been so extremely kind to us with several days of great weather while we had a high pressure system over us. We enjoyed spectacular sunrises and sunsets, cloudless days and calm seas.
Now… we have a low pressure system on top of us. Last night, we experienced 35 knot winds and 12 foot seas. I have spent a lot of time in my room in the past 24 hours… Late this morning, the sun came out and the winds calmed down, but the barometric pressure was still very low (around 990 mbars) which basically meant we were in the center of the low pressure system (similar to the eye of a hurricane, but not as strong… thank goodness!). We had a few hours relief, but we are back to pounding through the waves as the wind picks back up. It will be another long and sleepless night for this landlubber…
On a positive note, we did see two Laysan Albatrosses (Phoebastria immutabilis) from the Bridge as the winds began to kick up. They seemed to really enjoy the high winds as they soared effortlessly around the ship. The Officer on Deck (OOD) also said he saw a humpback breaching, but by the time I got up to the Bridge, it had moved on…
Next blog, I will share pictures of my room, the galley, “the cave,” the Bridge, etc. Right now, I am just trying to hold on to my mattress and my stomach…
Ship speed: 3.8 knots (4.4 mph) currently fishing
Weather Data from the Bridge
Wind Speed: 6.9 knots (7.9 mph)
Wind Direction: 30°T
Wave Height: 2ft with 2-4ft swells
Surface Water Temperature: 8.7°C ( 47.7°F)
Air Temperature: 7.9°C ( 46.2°F)
Barometric pressure: 1005.8 millibar (0.99 atm)
Science and Technology Log:
Since the main goal of this voyage is the acoustic-trawl survey of the mid-water portion of the Alaskan pollock population, I thought I would start by telling you how we go fishing to catch pollock! This isn’t the type of fishing I’m used to… Alaskan pollock is a semi-demersal species, which means it inhabits from the middle of the water column (mid-water) downward to the seafloor. This mid-water survey is typically carried out once every two years. Another NOAA Fisheries survey, the bottom trawl survey, surveys the bottom-dwelling or demersal portion of the pollock population every year. I will begin by describing how we are fishing for pollock on this acoustic-trawl survey.
The Oscar Dyson carries two different types of trawling nets for capturing fish as part of the mid-water survey, the AWT (Aleutian Wing Trawl which is a mid-water trawl net) and the 83-112 (a bottom-trawl net that is named for the length of its 83 foot long head rope that is at the top of the mouth of the net and the 112 foot long weighted foot rope at the bottom of the mouth of the net). One of the research projects on board the Oscar Dyson is a feasibility study that involves a comparison of the AWT and using the 83-112 bottom-trawl net as if it were a mid-water net. The 83-112 is much smaller than the AWT, so there is concern with the fish avoiding this net and thus causing a reduction in catch. While the bottom trawl survey acquires good information on the bottom-dwelling pollock using the 83-112 bottom trawl, if they also used this net to sample in mid-water they could help “fill in” estimates of mid-water dwelling pollock in years when the acoustic mid-water trawl survey does not occur.
When the net is deployed from the ship, the first part of the net in the water is called the cod end. This is where the caught fish end up. The mesh size of the net gets smaller and smaller until the mesh size at the cod end is only ½ inch (The mesh size at the mouth of the net is over 3 meters!).
The AWT is also outfitted with a Cam-Trawl, which is the next major part that hits the water. This is a pair of cameras that help scientists identify and measure the fish that are caught in the net. Eventually, this technology might be used to allow scientists to gather data on fish biomass without having to actually collect any fish (more on this technology later). This piece of equipment has to be “sewn” into the side of the net each time the crew is instructed to deploy the AWT. The crew uses a special type of knot called a “zipper” knot, which allows them to untie the entire length of knots with one pull on the end much like yarn from a sweater comes unraveled.
Along the head rope, there is a piece of net called the “kite” where a series of sensors are attached to help the scientists gather data about the depth of the net, the shape of the net underwater, how large the net opening is, determine if the net is tangled, how far the net is off the bottom, and see an acoustic signal if fish are actually going into the net (more on these sensors later, although the major acoustic sensor is affectionately called the “turtle”).
Once the kite is deployed, a pair of tom weights (each weighing 250 lbs), are attached to the bridal cables to help separate the head rope from the foot rope and ensure the mouth of the net will open. Then, after a good length of cable is let out, the crew transfers the net from the net reel to the two tuna towers and attach the doors. The doors act as hydrofoils and create drag to ensure the net mouth opens wide. Our AWT net usually has a 25 meter opening from head rope to foot rope and a 35 meter opening from side to side.
The scientists use acoustic data to determine at what depth they should fish, then the OOD (Officer on Deck) uses a scope table to determine how much cable to let out in order to reach our target depth. Adjustments to the depth of the head rope can be made by adjusting speed and/or adjusting the length of cable released.
The scientists use more acoustic data sent from the “turtle” to determine when enough fish are caught to have a scientifically viable sample size, then the entire net is hauled in. Once on board, the crew uses a crane to lift the cod end over to the lift-table. The lift-table then dumps the catch into the fish lab where the fish get sorted on a conveyor belt. More on acoustics and what happens in the fish lab in my next blog!
WOW! What an adventure!!! So I must get you caught up on some of the happenings thus far. After a mix-up where my reservation was cancelled on the Saturday afternoon flight from Anchorage to Dutch Harbor and the threat of being stranded in Anchorage for another day, I finally made it to Dutch. The weather cooperated (which is not the case more often than not), and we landed on Dutch Harbor after a quick refueling stop in King Salmon. Since we landed after 8pm, we went straight to one of the few restaurants in Dutch Harbor and had a late dinner before heading to the Oscar Dyson for the night.
Sunday morning, we went with several of the scientists out to Alaska Ship Supply to get some gear. I picked up my obligatory “Deadliest Catch” shirt and hat as all tourists do here in Dutch Harbor. We made three trips to the airport throughout the day to see if some of the science gear and luggage came, but came back disappointed. On one of our trips to the airport, we had lunch at the airport restaurant. I had Vietnamese Pho, which is a beef noodle soup, but it wasn’t nearly as good as the Pho my wife makes. 🙂 We also drove up the “Tsunami Evacuation Route” to an overlook where we could see all of Dutch Harbor and the town of Unalaska. Later, we drove around Unalaska and stopped to check out some tidal pools on our way back to the Oscar Dyson. In the afternoon, we checked out the World War II museum that was absolutely fascinating! I did not know Dutch Harbor was bombed by the Japanese and that so many American soldiers were stationed in the bunkers surrounding the harbor. For dinner, I had black cod (sablefish) at the Grand Aleutian Hotel. Yummy!
Monday we embarked on our adventure shortly after noon. We had to leave the dock because another ship was scheduled to offload there in the afternoon. The scientists’ equipment arrived on a late Monday morning cargo flight, but they didn’t make it to the ship on time!!! We couldn’t go to sea without them, so we deployed the “Peggy D” to go pick them up and bring them aboard!
Once we had our missing scientists, we left the safety of Dutch Harbor and ventured into open water. On our way, we saw dozens of humpback whales! None of the whales breached (jumped out of the water), but several of them fluked (dove and put their tail out of the water).
We started our day and a half journey to get to the starting point of our survey transects (the end point of last month’s survey). On our trip out, we experienced 6 to 10 ft seas and a 25 knot wind. It was a “gentle” welcome to the Bering Sea, but I struggled to get my sea legs underneath me. Meclizine is great motion sickness medication, but it sure knocked me out. I feel better now that I am not taking anything and am used to the rocking deck. While we made our way to our first transect, we had a couple of emergency drills. Here I am with fellow Teacher at Sea, Johanna, in our immersion suits as we completed our abandon ship drill.
On Wednesday morning, we began our first transect and did our first trawl along the transect (more on that later). I learned how to work in the fish lab collecting biological data on the catch we brought on board. I have been struggling to adjust to both my shift, which is 4am to 4pm, and the fact that the sun sets around 1am and rises at about 7am.
Thursday morning I woke on time and observed the survey scientists and crew deploying the CTD (Conductivity, Temperature, Depth) rosette from the hero deck (on the starboard side).
We also had beautiful clear skies and I was able to see Venus and Jupiter. At sunrise, I saw the GREEN FLASH!!! It was a beautiful start to the day.
We processed one mid-water AWT (Aleutian Wing Trawl) trawl that was all pollock, then switched to the 83-112 bottom trawl net (83 foot long head-rope and 112 foot long foot-rope) and pulled up a lot of jellyfish with our pollock.
Last night, I finally got a really good night sleep! This morning (Friday), I watched the CTD deployment again and learned more about the data being collected (more on this later). No spectacular sunrise this morning as it was the typical gray, foggy weather. I went up and spent some time on the bridge and Chelsea, our navigator/medic, taught me a lot about the instrumentation used for navigating the ship. There sure is a lot of technology on board!!!
From the bridge, we saw a pod of Dall’s Porpoise feeding, splashing around, and moving fast! We processed another AWT trawl of pollock that had quite a few herring mixed in. We traveled further into Russian waters than originally anticipated as we tried to identify the northern boundaries of the pollock population to get the best picture of the entire pollock range. We spotted a huge Russian trawler from the bridge!
We then headed south again towards American waters, but needed to do a quick water column profile test. Since we did not want to stop to drop the CTD again, I got to deploy a XBT (Expendable Bathythermograph)! After all the talk about safety briefings, the use of ballistics, and outfitting me with every piece of safety gear we could muster, I got ready to fire the XBT!!! Turns out, when you pull the firing pin, the XBT just slides out of the tube… no fireworks, no big bang… just a small kurplunk as the XBT enters the water. We all had a good laugh at my expense. See, scientists know how to have fun!
WOW! So I have just scratched the surface of our voyage thus far! Next time, I will give you a snapshot of what life was like aboard the ship.
NOAA Teacher at Sea Johanna Mendillo Aboard NOAA Ship Oscar Dyson July 23 – August 10, 2012
Mission: Pollock Survey Geographical area of the cruise: Bering Sea Date: Friday, July 27, 2012
Location Data from the Bridge: Latitude: 63○ 12’ N
Longitude: 177○ 47’ W
Ship speed: 11.7 knots (13.5 mph)
Weather Data from the Bridge:
Air temperature: 7.2○C (44.9ºF)
Surface water temperature: 7.2○C (44.9ºF)
Wind speed: 13.3 knots (15.3 mph)
Wind direction: 299○T
Barometric pressure: 1001 millibar (0.99 atm)
Science and Technology Log:
Greeting from the Bering Sea! It was a long journey to get here, complete with bad weather, aborted landings on the Aleutians, a return and overnight in Anchorage, and lost luggage, but it was a good introduction to the whims of nature and a good reminder that the best laid intentions can often go awry. As O’Bryant students know, our motto is PRIDE and the “P” stands for perseverance, so I simply stayed the course and made it to Dutch Harbor and NOAA Ship Oscar Dyson… only 29hrs late!
In upcoming posts, you will learn a lot about the acoustic technology, statistics, and the engineering know-how behind the trawling process and how it is used to find, collect, and study Pollock populations. But first, let’s start with splitting open some fish heads!
Now that I have your attention, let me explain. There are many steps involved in “processing” a net full of Pollock, and I will show you each soon, step-by-step. I think it would be more fun, though, to jump ahead and show you one little project I helped with that literally had me slicing open fish heads…