Andrea Schmuttermair, Pollock Processing Gone Wild, July 12, 2015

NOAA Teacher at Sea
Andrea Schmuttermair
Aboard NOAA Ship Oscar Dyson
July 6 – 25, 2015

Mission: Walleye Pollock Survey
Geographical area of cruise: Gulf of Alaska
Date: July 12, 2015

Weather Data from the Bridge:
Latitude: 55 25.5N
Longitude: 155 44.2W
Sea wave height: 2ft
Wind Speed: 17 knots
Wind Direction: 244 degrees
Visibility: 10nm
Air Temperature: 11.4 C
Barometric Pressure: 1002.4 mbar
Sky:  Overcast

Science and Technology Log

I’m sure you’re all wondering what the day-to-day life of a scientist is on this ship. As I said before, there are several projects going on, with the focus being on assessing the walleye pollock population. In my last post I talked about the transducers we have on the ship that help us detect fish and other ocean life beneath the surface of the ocean. So what happens with all these fish we are detecting?

The echogram that shows data from the transducers.

The echogram that shows data from the transducers.

The transducers are running constantly as the ship runs, and the information is received through the software on the computers we see in the acoustics lab. The officers running the ship, who are positioned on the bridge, also have access to this information. The scientists and officers are in constant  communication, as the officers are responsible for driving the ship to specific locations along a pre-determined track. The echograms (type of graph) that are displayed on the computers show scientists where the bottom of the ocean floor is, and also show them where there are various concentrations of fish.

This is a picture of pollock entering the net taken  from the CamTrawl.

This is a picture of pollock entering the net taken from the CamTrawl.

When there is a significant concentration of pollock, or when the data show something unique, scientists might decide to “go fishing”. Here they collect a sample in order to see if what they are seeing on the echogram matches what comes up in the catch. Typically we use the Aleutian wing trawl (AWT) to conduct a mid-water trawl. The AWT is 140 m long and can descend anywhere from 30-1,000 meters into the ocean. A net sounder is mounted at the top of the net opening. It transmits acoustic images of fish inside and outside of the net in real time and is displayed on a bridge computer to aide the fishing operation. At the entrance to the codend (at the end of the net) a CamTrawl takes images of what is entering the net.

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Once the AWT is deployed to the pre-determined depth, the scientists carefully monitor acoustic images to catch an appropriate sample. Deploying the net is quite a process, and requires careful communication between the bridge officers and the deck crew. It takes about an hour for the net to go from its home on deck to its desired depth, and sometimes longer if it is heading into deeper waters. They aim to collect roughly 500 fish in order to take a subsample of about 300 fish. Sometimes the trawl net will be down for less than 5 minutes, and other times it will be down longer. Scientists are very meticulous about monitoring the amount of fish that goes into the net because they do not want to take a larger sample than needed. Once they have determined they have the appropriate amount, the net is hauled back onto the back deck and lowered to a table that leads into the wet lab for processing.

Here the scientists, LT Rhodes, and ENS Kaiser assess the catch.

Here the scientists, LT Rhodes, and ENS Kaiser assess the catch.

We begin by sorting through the catch and pulling out anything that is not pollock. We don’t typically have too much variety in our catches, as pollock is the main fish that we are after. We have, however, pulled in a few squid, isopods, cod, and several jellies. All of the pollock in the catch gets weighed, and then a sub-sample of the catch is processed further. A subsample of 30 pollock is taken to measure, weigh, collect otoliths from, and occasionally we will also take ovaries from the females. There are some scientists back in the lab in Seattle that are working on special projects related to pollock, and we also help these scientists in the lab collect their data.

The rest of the sub-sample (roughly 300 pollock) is sexed and divided into a male (blokes) and female (sheilas) section of the table. From there, the males and females are measured for their length. The icthystick, the tool we use to measure the length of each fish, is pretty neat because it uses a magnet to send the length of the fish directly to the computer system we use to collect the data, CLAMS. CLAMS stands for Catch Logger for Acoustic Midwater Survey. In the CLAMS system, a histogram is made, and we post the graphs in the acoustics lab for review. The majority of our pollock so far have been year 3. Scientists know this based on the length of pollock in our catch. Once all of the fish have been processed, we have to make sure to clean up the lab too. This is a time I am definitely thankful we have foul weather gear, which consists of rubber boots, pants, jackets and gloves. Fish scales and guts can get everywhere!

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Personal Log

Here is one of many jellies that we caught. .

Here is one of many jellies that we caught. .

I am finally adjusting to my nighttime shift schedule, which took a few days to get used to. Luckily, we do have a few hours of darkness (from about midnight until 6am), which makes it easier to fall asleep. My shift runs from 4pm-4am, and I usually head to bed not long after my shift is over, and get up around noontime to begin my day. It’s a little strange to be waking up so late in the day, and while it is clearly afternoon time when I emerge from my room, I still greet everyone with a good morning. The eating schedule has taken some getting used to- I find that I still want to have breakfast when I get up. Dinner is served at 5pm, but since I eat breakfast around 1 or 2pm, I typically make myself a plate and set it aside for later in the evening when I’m hungry again. I’ll admit it’s a little strange to be eating dinner at midnight. There is no shortage of food on board, and our stewards make sure there are plenty of snacks available around the clock. Salad and fruit are always options, as well as some less healthy but equally tasty snacks. It’s hard to resist some of the goodies we have!

Luckily, we are equipped with some exercise equipment on board to battle those snacks, which is helpful as you can only walk so far around the ship. I’m a fan of the rowing machine, and you feel like you’re on the water when the boat is rocking heavily. We have some free weights, an exercise bike and even a punching bag. I typically work out during some of my free time, which keeps me from going too crazy when we’re sitting for long periods of time in the lab.

Up on the bridge making the turn for our next transect.

Up on the bridge making the turn for our next transect.

During the rest of my free time, you might find me hanging out in the lounge watching a movie (occasionally), but most of the time you’ll find me up on the bridge watching for whales or other sea life. The bridge is probably one of my favorite places on the ship, as it is equipped with windows all around, and binoculars for checking out the wildlife. When the weather is nice, it is a great place to sit outside and soak in a little vitamin D. I love the fact that even the crew members that have been on this ship for several years love seeing the wildlife, and never tire of looking out for whales. So far, we’ve seen orcas, humpbacks, fin whales, and Dall’s porpoises.

 

 

 

Did you know? Otoliths, which are made of calcium carbonate, are unique to each species of fish.

Where on the ship is Wilson?

Wilson the ring tail camo shark is at it again! He has been exploring the ship even more and made his way here. Can you guess where he is now?

Where's Wilson?

Where’s Wilson?

Where's Wilson?

Where’s Wilson?

Kacey Shaffer: All Good Things… August 13, 2014

NOAA Teacher at Sea

Kacey Shaffer

Aboard NOAA Ship Oscar Dyson

July 26 – August 13, 2014

Mission: Walleye Pollock Survey

Geographical Location: Bering Sea

Date: August 13, 2014

Weather information from the Bridge:

Air Temperature: 12º C

Wind Speed: 10 knots

Wind Direction: 306.62 º

Weather Conditions: Clear

Latitude: 53º 51.38 N

Longitude: 166º 34.85 W

Science and Technology Log:

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

Drop TS – Dropped Target Strength System

CTD – Conductivity, Temperature and Depth System

SBE – Sea-bird Electronics Temperature-Depth Recorder

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.

Kacey's first haul on the Oscar Dyson.

Kacey’s 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.

Personal Log:

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!

Kacey stands by one of four diesel engines on the Oscar Dyson.

Kacey stands by one of four diesel engines on the Oscar Dyson. (Photo credit: Sweet William)

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 shaft of the Oscar Dyson.

The shaft of the Oscar Dyson.

 

Engineering Operation Station

Engineering Operation Station

The EOS, or Engineering Operation Station, is the fifth location where the ship can be controlled. The other four locations are on the Bridge.

Engine Data Screen provides information about the engines, generators and shaft.

Engine Data Screen provides information about the engines, generators and shaft.

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.

The port side winch of the Oscar Dyson.

The port side winch of the Oscar Dyson.

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.

Kacey Shaffer: Fish Scales. Fish Tales. August 8, 2014

NOAA Teacher at Sea

Kacey Shaffer

Aboard NOAA Ship Oscar Dyson

July 26 – August 13, 2014

 

Mission: Walleye Pollock Survey

Geographical Location: Bering Sea

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…

 

This is the gear you'll need in the Wet Lab. It can get pretty slimy in there! (Photo Credit: Emily)

This is the gear you’ll need in the Wet Lab. It can get pretty slimy in there! (Photo Credit: Emily)

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.

 

Kacey lifts the door on the table so the fish will slide down onto the conveyor belt. This is when other species are pulled out. (Photo Credit: Sandi)

Kacey lifts the door on the table so the fish will slide down onto the conveyor belt. This is when other species are pulled out. (Photo Credit: Sandi)

At the end of the conveyor belt, Pollock are put into baskets, weighed and put into the sorting bin. (Photo Credit: Sandi)

At the end of the conveyor belt, Pollock are put into baskets, weighed and put into the sorting bin. (Photo Credit: Sandi)

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.

 

This is the sorting bin. Can you guess what Blokes and Sheilas means?

This is the sorting bin. Can you guess what Blokes and Sheilas means?

The white, rope-like structure is the male reproductive organ.

The white, rope-like structure is the male reproductive organ.

The pinkish colored sac is one of the female's ovaries. It contains thousands of eggs!

The pinkish colored sac is one of the female’s ovaries. It contains thousands of eggs!

Kacey uses a scalpel to cut the fish. She slides the liver out and looks for the reproductive organs. Is it a male or female? (Photo Credit: Darin)

Kacey uses a scalpel to cut the fish. She slides the liver out and looks for the reproductive organs. Is it a male or female? (Photo Credit: Darin)

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!

The Ichthystick is used to record the length of fish. A special tool held in the hand has a magnet inside that makes a connection with a magnet strip inside the board. It automatically registers a length and records it in a computer program called Clams

The Ichthystick is used to record the length of fish. A special tool held in the hand has a magnet inside that makes a connection with a magnet strip inside the board. It automatically registers a length and records it in a computer program called Clams

Kacey measures the length of a male with the Ichthystick. She holds the tool in her right hand and places it at the fork in the fish’s tail. A special sound alerts her when the data is recorded. (Photo Credit: Darin)

Kacey measures the length of a male with the Ichthystick. She holds the tool in her right hand and places it at the fork in the fish’s tail. A special sound alerts her when the data is recorded. (Photo Credit: Darin)

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!

Kacey scans a barcode placed on an otolith vial. Robert is removing the otoliths from each fish and Kacey places them in the vial. It is important to make sure the otoliths are placed in the vial that corresponds to the fish Robert measured. (Photo Credit: Emily)

Kacey scans a barcode placed on an otolith vial. Robert is removing the otoliths from each fish and Kacey places them in the vial. It is important to make sure the otoliths are placed in the vial that corresponds to the fish Robert measured. (Photo Credit: Emily)

 

Kacey removes an otolith from a fish Robert cut open. The otoliths are placed in the vial Kacey is holding. (Photo Credit: Emily)

Kacey removes an otolith from a fish Robert cut open. The otoliths are placed in the vial Kacey is holding. (Photo Credit: Emily)

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!

Personal Log:

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).

Mess Deck on the Oscar Dyson.

Mess Deck on the Oscar Dyson.

Mess Deck on the Oscar Dyson. Can you guess why there are tennis balls on the legs of the chairs?

Mess Deck on the Oscar Dyson. Can you guess why there are tennis balls on the legs of the chairs?

There are always multiple options for every meal. If you’re hungry on this ship you must be the pickiest eater on Earth!

There are always multiple options for every meal. If you’re hungry on this ship you must be the pickiest eater on Earth!

Did you know?

Not only are otoliths useful to scientists during stock assessment, they help the fish with balance, movement and hearing.

Allan Phipps: Fish heads, fish heads, rolly polly fish heads…. July 31, 2012

NOAA Teacher at Sea
Allan Phipps
Aboard NOAA Ship Oscar Dyson
July 23 – August 11, 2012

Mission: Alaskan Pollock Mid-water Acoustic Survey
Geographical Area: Bering Sea
Date: July 31, 2012

Location Data
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.

Walleye pollock on the sorting table. Various age groups are seen here, including one that is 70cm long and may be over 12 years old! Most are 2 to 4 year olds.

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.

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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 CLAMS display showing that I am “today’s scientist.”

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.”

Making incision to determine gender on pollock sample.

Hopper for female pollock ready to be measured with the Ichthystick and entered into CLAMS.

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.

The Ichthystick with fingertip magnet used to quickly measure and enter length data into CLAMS.

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.

Incision across the skull revealing the otoliths on either side of the brain stem.

One otolith from a Walleye pollock.

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!

Personal Log:

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.

Sunny skies and calm seas on the Oscar Dyson.

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…

Jessie Soder: Steamin’ and Swimmin’, August 10, 2011

NOAA Teacher at Sea
Jessie Soder
Aboard NOAA Ship Delaware II
August 8 – 19, 2011 

Mission: Atlantic Surfclam and Ocean Quahog Survey
Geographical Area of Cruise:  Northern Atlantic
Date: Wednesday, August 10, 2011 

Weather Data
Time:  16:00
Location:  40°41.716N, 67°36.233W
Air temp: 20.6° C (69° F)
Water temp: 17° C (63° F)
Wind direction: West
Wind speed: 11 knots
Sea wave height: 3 feet
Sea swell:  5-6 feet 

Science and Technology Log

View from the flying bridge departing Woods Hole

Our departure from Woods Hole has been delayed a number of times due to several factors.  We were scheduled to leave the dock on Monday at 2pm, but due to rough seas (8ft on Georges Bank—which was where we were planning to go first) and a crane that needed to be fixed our departure was rescheduled for Tuesday at 10am.  On Tuesday, the crane was fixed, but then it was discovered that the ship’s engineering alarm system was not working properly, so our departure was delayed again for a few hours.  The crew worked hard to get the ship off the dock and we departed at 1:15 on Tuesday.  Yay!  We were on our way to Georges Bank, which was about a 15 hour “steam,” or, trip.

The purpose of the NOAA Fisheries Atlantic surfclam and ocean quahog survey is to determine and keep track of the population of both species.  This particular survey is done every three years.  NOAA Fisheries surveys other species too, such as ground fish (cod, haddock, pollock, fluke), sea scallops, and northern shrimp.  These species are surveyed more often—usually a couple of times each year.  Atlantic surfclams and ocean quahogs are surveyed less often than other fished species because they do not grow as fast as other species.  In fact, the ocean quahog can live for more than 150 years, but it only reaches about 6  inches across!  In comparison, the sea scallop lives for only 10 to 15 years and reaches a size of 8 inches.

There are 27 people on board this cruise.  Each person is assigned a watch, or shift, so that there are people working 24 hours a day. The work never stops!  Seventeen people on board are members of the crew that are responsible for the operation and navigation of the ship, machinery operation and upkeep (crane, dredge, etc.), food preparation, general maintenance, and electronics operations and repair.  There are a lot of things that need to happen to make things on a research ship run smoothly in order for the scientific work to happen!

NOAA Ship Delaware II docked in Woods Hole

Twelve people on board are part of the science team, including me, who collect the samples and record the data.  We are split into two watches, the noon-midnight watch and the midnight-noon watch.  We sort through the material in the dredge for the clams and the quahogs.  We measure and weigh them as well as document the location where they are collected.  Several members of the science team are volunteers.

Personal Log

A swimming beach near Nobska Lighthouse

Our delayed departure has given me a lot of time to talk to crew and to explore Woods Hole—which I have really enjoyed.  I have learned a lot about the responsibilities of the different members of the crew and about the maritime industry, which is something that has always interested me.  I was also able to visit the Woods Hole aquarium (twice!) and attend a talk given by crew from the R/V Knorr. The Woods Hole Oceanographic Institute operates the R/V Knorr and it was on this ship that the location of the wreck of the Titanic was located for the first time in 1985.  Additionally,  in 1977 scientists aboard this ship discovered  hydrothermal vents  on the ocean floor.  And, lastly, I had time to go swimming in the Atlantic Ocean!  The water was a bit warmer off the coast of Massachusetts than it is off the coast of Alaska…

Questions to Ponder

What is the difference between an ocean quahog and an Atlantic surfclam?