NOAA TEACHER AT SEA CATHRINE PRENOT FOX NOAA SHIP OSCAR DYSON JULY 24 – AUGUST 14, 2011
Personal Log:
I have not always had the best morals when it came to eating seafood. I discovered the joys of sushi in San Francisco after I graduated college. There was one place that I would frequent so often that the sushi chefs would would create something for me when I walked through the door. I later learned from Ruth Reichl in her book Garlic and Sapphires that the phrase I was looking for was “Omakase.” Literally: I am in your hands. In their capable hands I tried unagi (eel), hon maguro (bluefin tuna), and hamachi (yellowtail) for the first time. And I fell in love.
A few years later, a friend mentioned to me that I might want to moderate my adoration of some fish. Never one to take someone else’s word, I did my own research. I read, with growing horror, that my delicious eel farms were not sustainable, and that bluefin tuna was declining worldwide. Evidently, there were so many others that shared my love of the cool simple taste of hon maguro that we were loving these and other species to death. I know, you probably don’t want to take my word for it. Do your own research and then come back: FishWatch and SeaFoodWatch.
Back? Did you see that Yellowfin tuna are being sustainably harvested? Yes, me too. One order of hamachi sashimi, please.
What is my point with all of this? I want to show you what data are used to make these determinations about sustainability. I assure you, it is not random or haphazard. In fact, the purpose of my time in Alaska was to provide data to fisheries managers (composed of teams of fishermen, scientists, and officials) to let them make educated decisions on the health of walleye pollock populations in the Gulf of Alaska. What data do we collect? How do we know what the fish are doing, and how many there are? It isn’t an easy job… there is no Walleye Pollock Facebook Status Page that you can just check… (Cartoon citations 1, 2, and 3). You have to get dirty and do some real science.
Adventures in a Blue World, Issue 13
Until our next adventure,
Cat
Walleye Pollock age classes.
p.s. Although my “real job” has severely impacted the amount of time I have to cartoon, I am still working on at least two more (and up to seven, if I find a way to get a hold of a Time-Turnerlike Hermione Granger) cartoons. Thank you for being patient!
NOAA Teacher at Sea
Lindsay Knippenberg
Aboard NOAA Ship Oscar Dyson
September 4 – 16, 2011
Mission: Bering-Aleutian Salmon International Survey (BASIS) Geographical Area: Bering Sea Date: September 11, 2011
Weather Data from the Bridge Latitude: 58.00 N
Longitude: -166.91 W
Wind Speed: 23.91 kts with gusts over 30 kts
Wave Height: 10 – 13ft with some bigger swells rolling through
Surface Water Temperature: 6.3 C
Air Temperature: 8.0 C
Science and Technology Log
On a calm day letting out the CTD is easy.
Today Jeanette and Florence took me under their wing to teach me about the oceanographic research they are conducting onboard the Dyson. At every station there is a specific order to how we sample. First the transducer, then the CTD, then numerous types of plankton nets, and then we end with the fishing trawl. The majority of the oceanographic data that they collect comes from the CTD (Conductivity, Temperature, Depth). The CTD is lowered over the side of the ship and as it slowly descends to about 100 meters it takes conductivity, temperature, and depth readings. Those readings go to a computer inside the dry lab where Jeanette is watching to record where the pycnocline is located.
The results from the CTD. Can you spot where the pycnocline is?
The pycnocline is a sharp boundary layer where the density of the water rapidly changes. The density changes because cold water is more dense than warm water and water with a higher salinity is more dense than water that is lower in salinity. So as the CTD travels down towards the bottom it measures warmer, less salty water near the surface, a dramatic change of temperature and salinity at the pycnocline, and then colder, saltier water below the pycnocline. Once Jeanette knows where the pycnocline is, she tells the CTD to collect water at depths below, above, and at the pycnocline boundary. The water is collected in niskin bottles and when the CTD is back on deck Florence and Jeanette take samples of the water to examine in the wet lab.
Filtering out the chlorophyll from the CTD water samples.
Back in the lab, Jeanette and Florence run several tests on the water that they collected. The first test that I watched them do was for chlorophyll. They used a vacuum to draw the water through two filters that filtered out the chlorophyll from the water. As the water from the CTD passed through the filters, the different sizes of chlorophyll would get stuck on the filter paper. Jeanette and Florence then collected the filter paper, placed them in labeled tubes, and stored them in a cold, dark freezer where the chlorophyll would not degrade. In the next couple of days the chlorophyll samples that they collected will be ran through a fluorometer which will quantify how much chlorophyll is actually in their samples.
Jeanette collecting water from the CTD.
Besides chlorophyll, Jeanette and Florence also tested the water for dissolved oxygen and nutrients like nitrates and phosphates. All of these tests will give the scientists a snapshot of the physical and biological characteristics of the Eastern Bering Sea at this time of year. This is very important to the fisheries research because it can help to determine the health of the ecosystem and return of the fish in the following year.
Personal Log
One of the high points for me so far on the cruise has been seeing and learning about all the new fish that we catch in the net. We have caught lots of salmon, pollock, and capelin. The capelin are funny because they smell exactly like cucumbers. When we get a big catch of capelin the entire fish lab smells like cucumbers…it’s so weird. We have also caught wolffish, yellow fin sole, herring, and a lot of different types of jellyfish. The jellies are fun because they come in all different shapes and sizes. We had a catch today that had some hug ones and everyone was taking their pictures with them.
Now that is a big jelly fish.
Today we also caught three large Chinook or king salmon. Ellen taught me how to fillet a fish and I practiced on a smaller fish and then filleted the salmon for the cook. What is even cooler was that at dinner we had salmon and it was the fish that we had caught and I had filleted. Fresh salmon is so good and I think the crew was happy to get to enjoy our catch.
The catch of the day was a 8.5 kg Chinook salmon.Salmon for dinner, filleted by Lindsay.
NOAA Teacher at Sea
Lindsay Knippenberg
Aboard NOAA Ship Oscar Dyson
September 4 – 16, 2011
Mission: Bering-Aleutian Salmon International Survey (BASIS) Geographical Area: Bering Sea Date: September 8, 2011
Weather Data from the Bridge Latitude: 54.14 N
Longitude: -166.57 W
Wind Speed: 27.33kts
Wave Height: up to 17 ft
Surface Water Temperature: 8.4 °C
Air Temperature: 7.7 °C
While hiding from the storm in Dutch Harbor for the past two days, I had plenty of time to explore my new home onboard the Oscar Dyson. The Dyson is 209 ft in length and is like a small city. Everything that I would need during my two-week cruise, including a laundry room, would be available to me onboard. To show you what life is like onboard a ship, I decided to go on a little tour of the Dyson and take some pictures of the different areas of the ship. If you are interested in more in-depth specifications of the ship, check out the Oscar Dyson’s website.
Science and Technology Log
Let’s start in the scientific areas of the ship. I have been spending most of my time working with the fisheries team in the fish lab. When we are done trawling and the fishermen bring in the net, they dump our catch onto a large conveyor belt. As the conveyor belt slowly moves, we sort our catch by species. Once we are done sorting, we also process the catch by weighing, measuring, and taking samples of the organisms. To learn more about this process, see my blog post from September 4th.
The Fish Lab. This is where the fish are brought in and processed.
Next to the fish lab is a wet lab. A lot goes on in the wet lab. Some scientists are identifying plankton under microscopes, other scientists are dissecting fish stomachs to see what the fish are eating, and some scientists are filtering water from different depths of the ocean looking for chlorophyll.
The Wet Lab. Scientists study the ocean water, use microscopes, and dissect fish stomachs in this lab.
When you pass through yet another door, you end up in another lab called the dry lab. There are several computers and other pieces of machinery that control the instruments that are lowered over the side of the ship at our sampling stations. This room is where a lot of the oceanography data is collected. I will talk about what they do and the data that they are collecting in another blog.
The Dry Lab. Jeanette is watching the data come in from one of the instruments.
The last lab is across the hall and it is called the acoustics lab. This room is mostly composed of computers and lots of large screens to track where the fish are underneath the boat. Stay tuned for more on acoustics later.
The Acoustics Lab. Paul is using acoustics to watch the fish swim under the boat.
Personal Log
I know that many of you have been wondering…Where do I sleep? What do I eat? What do I do when I am not playing with fish? And do I get to take a shower after playing with fish all day? Hopefully these pictures will help you to get a better idea of what life is like on the ship. It is no cruise ship, but I’m not “roughing it” by any means.
Let’s start with my room. The rooms are actually a lot larger than I thought that they would be. Everyone has a roommate and I am sharing a room with the Chief Scientist, Ellen Martinson. Each room has two bunks, a desk with an internet connection, two lockers for storing gear, a refrigerator, drawers for more storage, and a bathroom.
Mine and Ellen's room.
Ahh…the bathroom. Each room has its own bathroom with a sink, shower, and toilet. Before I got here I had imagined having one large bathroom for each floor or group of rooms, so this was a pleasant surprise. Even better was that it was much larger than any bathroom I have ever seen on a boat. The shower even has a bar to hold onto when you are trying to shower in rough seas, which I have found quite useful.
My Bathroom...it's so huge for a boat.
So what do I eat? It is more like what have I not eaten. The food has been excellent and there is always a variety of choices to choose from. Breakfast is from 07:00 – 8:00 and consists of eggs, bacon, sausage, pancakes or french toast, oatmeal, and today there was even quiche. I’m not a big breakfast person so I have been eating cereal and fruit for most breakfasts. Lunch is from 11:00 – 12:00 and is my favorite meal of the day. The cook makes amazing soups and there is usually a good sandwich to pair it with. If you don’t want soup and sandwich, there is usually burgers, quesadillas, or chicken fingers to choose from. If you don’t think that you can make it until 17:00 (or 5pm) when dinner is served again, don’t worry. There are usually fresh-baked cookies in the galley at around 15:00. If you still are hungry at dinner time, then you are in for a treat. So far for dinner I have had pork chops, spaghetti, leg of lamb, steak, and chicken ala king. Of course you would have to finish dinner with dessert and coffee. How about homemade chocolate cake and a scoop of ice cream? And you can’t just serve a regular cup of coffee. How about a mocha latte made from the espresso machine in the galley?
The Galley. Lots of good food can be found here.
What happens if you eat too much and get sick? Don’t worry, the ship has a medical officer and infirmary if you need medicine. We have had some pretty rough seas during our cruise so it is nice to know that there is somewhere that I can go if I am feeling sick or if I need more medicine.
Not feeling well? Don't worry, the ship has a medical officer and infirmary.
What do I do when I’m not playing with fish in the fish lab? Well, there are lots of things to do to keep yourself busy. You could workout in one of two workout rooms. You could choose from over 500 movies to watch in the lounge. You could clean your fish-smelling clothes in the laundry room. My personal favorite is to go up to the bridge and check out what is going on outside. From here you can see for miles and there are usually lots of seabirds to see and if you are lucky you can even see a whale or porpoise passing by.
Wash your dirty clothes at the ship's laundry room.
Relax in the lounge and watch a movie.Eat too many cookies today? Work off those extra calories in one of the ships two workout rooms.
Check out the bridge to look for sea birds and whales.
NOAA Teacher at Sea
Lindsay Knippenberg
Aboard NOAA Ship Oscar Dyson
September 4 – 16, 2011
Mission: Bering-Aleutian Salmon International Survey (BASIS) Geographical Area: Bering Sea Date: September 4, 2011
Weather Data from the Bridge
Latitude: 54.13
Longitude: -166.41
Wind Speed: 24.10kts
Wave Height: 4-6 ft
Surface Water Temperature: 9.0°C
Air Temperature: 8.8°C
Science and Technology Log
The station grid for all of the proposed sampling sites.
Yeah! Today we left Dutch Harbor and began the second leg of the Bering-Aleutian Salmon International Survey (BASIS). The purpose of the BASIS Study is to assess the status of marine species in the Eastern Bering Sea and support the decision making process for commercially important fisheries. The scientists on my team are accomplishing this goal by combining their knowledge of fisheries, oceanography, and acoustics. While I am onboard I will be helping out the scientists in all these different areas to get a broad view of all the science going on during our cruise.
There are specific sampling locations called stations that we will be going to throughout the Eastern Bering Sea. The map on the left shows the locations of these stations. The green dots are the stations that we are sampling during leg 1 and leg 2 of the BASIS survey. Leg 1 is already complete and they sampled at all the stations east of Unalaska. We will be picking up where they left off and sampling at all of the remaining green stations. The black dots are stations that will be sampled by another vessel named the Bristol Explorer.
The trawl net being let out behind the ship.
For the first station I got to help out the fisheries team in the fish lab. We did a surface trawl by letting out a large net out the back of the boat with floats on it to keep it at the surface. By adjusting the floats and weights on the trawl, the fishermen can choose what depth they fish at. While the net is out, the OOD (Officer of the Deck) slowly motors the ship for about 30 minutes and the net catches the fish that are swimming in that area and depth. For this station we want to see the fish that are swimming within the top 30 meters of our sampling area. At later stations we might also do a mid level or deep trawl to see the fish that live at those depths.
We found some Salmon!
After the 30 minutes were up, the fishermen slowly brought in the net and we immediately saw salmon caught in the net. Yeah! We caught something! As more and more net was brought in the fish began to pile up on our sorting table. There were a lot more fish than I had expected and the majority of them were salmon. It was now our job to sort the fish by species and I will admit that I am pretty slow at identifying the species. They may all look like fish, but they each have identifiable features like the color of their gums (black for Chinook Salmon), type of gill rakers, or color patterns on their body or tails. At this station we were lucky enough to pull in four out of the five salmon species in Alaska. We caught Chinook, Sockeye, Chum, and Pink Salmon. We also caught several different species of jellyfish and some squid.
That is a lot of salmon to sort.
After we caught the fish, we had to process them. In order to learn about the fish and the health of their population, we took samples and collected data from the fish we caught. Here is a description of the data we collected and what the scientists can learn from that data.
Weight and Length – Weight and length are an index of fitness for the fish. The scientists multiply how fat the fish is by how long it is to determine its lipid (fat) content. In cold waters the fish tend to have a higher lipid content than in warmer waters where the fish have to use more energy to metabolize. Additionally, if a fish has a higher lipid content, it might also mean that it is healthy and finding prey easily.
Gill rakers (white hairs on top of the red gills) from two different salmon. Can you see the difference?
Axillary Process – We cut the axillary process off the fish we caught for genetic studies. The scientists know the baseline genetic sequence for the salmon that come from different regions of the world. By looking at the genetics of the fish we caught, we can tell where the fish came from and reconstruct their migration and distribution. For instance, the scientists have used the genetics from the axillary processes to determine that a large percentage of chum salmon caught in the Eastern Bering Sea are from Japan.
Sexual Maturity – By looking at the testes and ovaries of the fish, the scientists can determine if the fish were immature or mature and when they were going to spawn. Using this information along with the results from the axillary process genetics, the scientists can determine migration patterns and growth rates.
Determining the sex, stomach contents, and sexual maturity of the fish we caught.
Male vs. Female – The scientists also use the testes and ovaries to determine if the fish was a female or male. This is helpful in looking at the ratio of males to females in their population.
Stomach Contents – By removing the stomach of the fish and analyzing its stomach contents, the scientists can determine what the fish was eating. This is can be very helpful when comparing warm years to cold years and the effect that climate change can have on prey sources and the nutrition of the fish.
All of this information can then be extremely useful to fisheries managers who are assessing the stock of the fish that are important to commercial fishermen. One of the species that we hope to collect as we sample at other stations is Pollock. Pollock is the largest US fishery by volume. Each year around 2.9 Billion pounds of Pollock are harvested. To learn more about the Pollock fishery check out this link to NOAA FishWatch. The scientists on my team are assessing the health of the Pollock fishery by looking at the total lipid content of Age 0 Pollock in late summer. Their lipid content is important at this time of year because winter in coming and they will need lipids to survive the cold winter. By looking at the lipid content of the Age 0 Pollock that we collect, the scientists can predict how many Age 0 Pollock will survive to become Age 1 Pollock and eventually mature to become Age 3 or 4 Pollock that can be harvested.
Personal Log
The fluke of a whale as it dives.
Whales! I was hanging out on the bridge getting my last look at land for a couple of weeks when I thought I saw a whale out of the corner of my eye. I couple of minutes later a huge Humpback Whale breached right next to the ship. I have seen whales before, but it was just their dorsal fin of flukes. This was crazy. An entire whale was out of the water and it kept on breaching over and over again like it was playing. I wanted to take a picture, but I was too mesmerized to even take my eyes away from it for a moment. Then as I started to look farther out to sea, I saw even more whales. There were about a dozen whales flapping their tails and rolling on to their sides. It looked like they were having a good time playing on a beautiful day.
The weather forecast for September 4 - 6. It doesn't look good...
That beautiful day, however, did not last very long. We managed to sample at two different stations when the wind started to pick up and the waves began to get a little larger. The forecast was calling for a Gale Warning with gusts of up to 50kts and 20-24 ft seas. Those conditions are far too dangerous to fish in, so we turned around and headed back to Dutch Harbor. Hopefully the storm will pass quickly and we will only have to hide out a couple of days until it is safe to fish again.
NOAA Teacher at Sea
Lindsay Knippenberg
Aboard NOAA Ship Oscar Dyson
September 4 – 16, 2011
Mission: Bering-Aleutian Salmon International Survey (BASIS) Geographical Area: Bering Sea Date: September 3, 2011
Weather/Location Data for Unalaska, AK Latitude: 53°54’0”N
Longitude: 166° 32′ 36″ W
Wind Speed: Calm
Air Temperature: mid 50’s°F
Personal Log
It was a long day of traveling. I flew from Washington DC to Seattle to Anchorage to Cold Bay to Dutch Harbor.
Whew…I made it to Unalaska. After an entire day of sitting on airplanes and running through airport terminals, I am finally here. I can’t believe how beautiful it is here. The surrounding mountains are a stunning green color and there have even been some sightings of blue sky between the normal grey clouds. I am also amazed at how warm it is. It almost got up to 60°F today, but I was told that the weather can change here pretty quickly. We have already heard of bad weather coming our way next week. The National Weather Service issued a Gale Warning with predictions of wind gusts of up to 50 knots and waves above 20 feet. I had better take my seasickness medications.
The beautiful town of Unalaska.
We don’t ship out until tomorrow, so we decided to take advantage of the nice weather and explore Unalaska. Unalaska is much bigger than I thought that it would be. It is a major international fishing port and is one of the larger cities in Alaska with about 4,000 residents. Life in Unalaska revolves around fishing. Most residents are either commercial fishermen, work in the processing facilities, support the fishermen through stores and other services, or work in the ship yards where the seafood is shipped to all parts of the world. The name of the harbor where all of this is going on might be familiar to you. It is called Dutch Harbor and is where the show “Deadliest Catch” is filmed about the commercial crab fishermen. Crab is not the only type of commercial seafood coming out of Dutch Harbor. Pollock, Cod, Halibut, Rock Sole, and Mackerel are just a few of the other commercial fisheries in Dutch Harbor.
A World War II bunker on top of Bunker Hill in Unalaska (Photo Credit: Jillian Worssam).
For those of you interested in history, Dutch Harbor also has historical significance from World War II. Dutch Harbor was the only land in North America, besides Pearl Harbor, that was bombed by Japanese Zeros during World War II. In our exploring around the island today, we saw evidence of Armed Forces’ bunkers, Quonset huts, and barracks still visible amongst the green hills of Unalaska. The National Park System opened a WWII National Historic Area and Visitor Center in 2002 in Unalaska and I hope to have time to visit it either before or after my cruise.
Enjoying the beach at Summer Bay in Humpy Cove. In 1997 this was the site of a 47,000 gallon oil spill
What’s the best place to go on a beautiful, sunny day in Unalaska? The beach, of course. We didn’t go to the beach to get sun tans or to go for a swim. We went to check out the tide pools. I love tide pools! It is amazing how resilient the little creatures are that live in the tide pools. When the tide is in they are completely submerged under water and then six hours later they are above the water level when the tide goes out. To make life even harder, they are also smashed by huge waves crashing on them as the tide goes in and out. It is a tough life, but there was such a diversity of life that they must be pretty tough and have some helpful adaptations. As I explored amongst the rocks, I found sea anemones, barnacles, mussels, and lots of different types of seaweeds. On our way back to the van, we also found a stream leading back to a brackish lake and the salmon were running. They are amazing creatures to watch too. The amount of energy that they exert and the sacrifice that they make to reproduce is incredible.
I am now a member of the female dominated science team onboard the Oscar Dyson.
Unfortunately we couldn’t spend our entire day exploring. The plan for the rest of the day is to get settled onboard the Dyson, have a science team meeting to discuss the science that we will be doing and the logistics associated with the different stations and sample sites, and have a safety meeting with the crew of Dyson to discuss life onboard the ship and emergency situations. I am so excited to go out to sea tomorrow and actually start fishing.
Leg 1 has concluded. Oscar Dyson is currently at port in Dutch Harbor. Please use link (NOAA Ship locator) to follow ship in future research cruises and current location/conditions.
Science and Technology Log
I am back home and my expedition aboard the Oscar Dyson has come to a conclusion. My travels home had me leaving Dutch Harbor at 7:30 PM and arriving into Newark, NJ the following day at 2:30 pm EST, an incredibly long, red-eye flight back home. Although my involvement aboard the ship has come and gone, the ship is currently in port at Dutch Harbor taking on more fuel and supplies and readying to do a “turnaround trip”. For Leg II they will be heading back out into the Bering Sea to obtain further data. The following is a map that depicts the stations for Leg 1 and 2. For Leg 1, all of the green stations (40#) represents the areas where we conducted our research. For Leg II, they will be focusing on the black circle stations. When all of this field work is complete, and the numbers are “crunched” they can be extrapolated out to get a better idea of the overall health of the Bering Sea ecosystem as detailed in prior blogs.
BASIS 2011 Station Grid
So, before I left Alaska, I was discussing a bloom and readying the blog platform for a discussion of zooplankton and other higher-ordered interactions of the Bering. Ok, so moving on…the next feeding level in the marine world would be the primary consumers….the zooplankton. Zooplankton, although a very simplified explanation, are essentially animals that drift (planktonic) while consuming phytoplankton (for the most part). These zooplankton in turn, are a resource for consumers on higher trophic levels such as the Pacific Cod, salmon, and Walleye Pollock (which are a primary focus on this survey). Zooplankton are typically small and in order to obtain samples from the sea, we have been utilizing specialized nets (information and pictures to follow) to extract, analyze and collect them for further investigations back at the lab.
The following picture is a good visual to represent this flow of energy that we have been discussing since the first Blog Entry. An important observation is that the sun is the “engine” that initiates all of these interactions. The exchange of carbon dioxide compliments of Photosynthesis and respiration, the abundance of phytoplankton in the photic zone (see last blog entry), which are food for the zooplankton, which in turn, become food for higher-order carnivores.
Marine Food Chain
One of the more important zooplankton species out in the Bering are the euphasiids. These are small invertebrates found in all of worlds oceans. The common name is Krill. These species are considered a huge part of the trophic level connection, feeding on the phytoplankton and converting this energy into a form suitable for the larger animals. In the last blog, I put in some pictures of euphasiids that we caught. These euphasiids have a very high lipid content (fat) and in turn, are what is responsible for getting salmon their richness in oily flesh, the Omega Fatty acids, and there natural, pink-fleshed color. I have read before about the differences between farm-raised vs. wild salmon from a nutritional standpoint. Farm-raised salmon often lack the abundant Omega oils that are found in the wild species. Also, it is true that in order for the farm-raised salmon to get their pinkish color to the flesh, they are fed a nutritional supplement to give the color….essentially, like adding a food dye. So, in class this year, we will have to be very careful when analyzing the pros and cons of aquaculture/fish-farming.
Personal Log
Although my official involvement with the Oscar Dyson has come to an end, I will take with me the experiences and knowledge for a lifetime. It was everything I was hoping it would be and then so much more. These blogs, the pictures, the video…… all do the expedition no justice. However, I have pledged to make every effort possible to spread the word about NOAA and its mission and this is exactly what I will do. I have several more decades of career in front of me and I know that between now and that date, I will use this recent expedition countless times and will hopefully convince the general public about the overall importance of government agencies like NOAA and how common resources must be valued and protected to ensure the health of all of Earth’s inhabitants.
There are so many people who I would like to thank for providing and delivering such an extraordinary experience. All of the crew aboard the Oscar Dyson, from the engineers, to the chef, and captain……Thank You. Your professionalism and ability were truly inspiring.
To the Scientists, You were really the “teachers at sea”. May you always continue your motivated path to revealing the beautiful secrets this planet has to offer. Also, my hope that it continues to be done in a fashion that I saw while during my time on the water…..In a professional, unbiased, non-political fashion. You have reassured my passion for the sciences and have given me fuel to disprove any “non-believers” who claim that the sciences have become corrupted. In the end, you have shown me the most universal and balanced approach at reaching the truth.
Weather Data from the Bridge
Latitude: 56.95N
Longitude: 162.93 W
Wind Speed: 10 Knots
Surface Water Temperature: 10.5 C
Air Temperature: 55F
Relative Humidity: 97%
Science and Technology Log:
Well, at this time tomorrow, the Oscar Dyson will be tied up in port at Dutch Harbor. This is our end destination for Leg I of the BASIS survey. I will write-up a summary/conclusion either at that time or shortly after getting back into town. For now, I will fill you in on some material that I promised. As noted in earlier blogs…I have been intentionally writing in a trophic bottom up approach. That is, I started my first blog entries with descriptions of the primary producers, the Phytoplankton. I covered this extensively and correlated it to the oceanographic work that has been going on aboard this ship. It seemed logical to work from the base of the food chain and work my way up the trophic levels to the more complex consumers.
However, before I close the chapter on Phytoplankton take a look at the picture I took below. When I stepped outside and saw this, I thought I had been transported to the Caribbean. Clear skies, calm seas, tropical blue waters are not typical descriptions for the Bering Sea. If you look closely enough, you can even see the shadow of the clouds on the surface of the sea. Science is the field of making observations, forming hypothesis, designing and conducting experiments and drawing conclusions about the natural world we live in. So…what would you make of this observation? What has caused this temporary “mirage” of tropics? Clearly something is going on here.
Coccolithophores 08-28-11
Well, although not 100% certain, the most likely explanation is what would be called a Coccolithophore bloom. These are single-celled algae which are characterised by special calcium carbonate plates as seen in photo below under magnification.
Coccolithophore
Under certain conditions, (some speculate that wind pattern changes fail to mix the water column favoring cocolithophore blooms as opposed to other plankton) coccolithophores can create large blooms turning the water brilliant shades of blue pending on the species of coccolithophore blooming at the time. Ed (Chief Scientist) was telling me of a major bloom that had occurred back in the late 90’s. I researched it a bit and the following picture is of this bloom in the same general vicinity where we are now. Amazing to think of how microscopic plants can influence a region on the scale of an entire sea and be seen from space. *Note: this is not a false colored Image
Coccolithophore Bloom 98 Bering Sea
There is also some speculation that these types of blooms may be linked to sub-average runs of salmon (and even impact seabirds negatively in the area). Some hypothesize that this may be due to the idea that salmon prey heavily upon euphausiids (see picture I took below on 08-28-11 and the one centered beneath for a closer look taken from NOAA) and the euphausiids have difficulty subsiding on the extremely small coccolithophores. Remember what I was saying about visualizing the flow of energy as a pyramid and the effects of taking out a few or many blocks that make up the base of the food chain.
euphausiids 08-28-11Euphasiid
Ok, to make this easier for the reader, I am going to stop this blog here and start a new one dedicated to the zooplankton…..I got a little sidetracked with the whole coccolithophore bloom event…….
Personal Log
Earlier this morning we were greeted with some higher winds and consequently some larger seas. As my friend back East says conditions got “Sporty.” Here is a picture from where we launch the CTD. Winds were out of the SW gusting to 30 knots and seas were in the 10′ range with some larger swells thrown into the mix to keep things interesting.
