Cristina Veresan, Sorting the Catch, August 5, 2015

NOAA Teacher at Sea
Cristina Veresan
Aboard NOAA Ship Oscar Dyson
July 28 – August 16, 2015 

Mission: Walleye Pollock Acoustic-Trawl Survey
Geographical area of cruise: Gulf of Alaska
Date: Wednesday, August 5, 2015

Data from the Bridge:
Latitude: 60° 46.4′ N
Longitude: 147° 41.0′ W
Sky: Clear
Visibility: 10 miles
Wind Direction: E
Wind speed: 5 knots
Sea Wave Height: 0-1 feet
Swell Wave: 0 feet
Sea Water Temperature: 16.8 °C
Dry Temperature: 16.0° C

Science and Technology Log

What about all those fish we bring onboard? Our Lab Lead Emily oversees the processing of the catch and determines which protocols or sampling strategies are most appropriate. She and I, along with the Survey Tech on duty, work together to identify, weigh, and measure the catch and collect any necessary biological samples such as otoliths or ovaries. The first job is to sort everything, and we continue sorting until the table is empty. We identify the creatures and organize them by species into different baskets. We end up with many baskets of pollock, usually hundreds of individuals. If distinct length groups of pollock are present we sort them by length (which is indicative of age class) and sample each group separately. All of the basket(s) are weighed to get a total weight per species (or length group) for the haul.

One of many baskets of pollock

One of many baskets of pollock

'Bloke' or 'Sheila' pollock? It's all sorted out here

‘Bloke’ or ‘Sheila’ pollock? It’s all sorted out here

For pollock estimated to be age two and older, we sex and length about 300 individuals per haul. When I say sex a pollock, I mean we must determine if the fish is male or female. Pollock do not have any external features to determine which sex they are so we must slice open the belly of the fish, pull back the liver and look for the gonads; females have a light pinkish to orange colored two-lobed ovary, while males have a whitish bubbled string of testes. The sex-sorting table has a large basin next to a partitioned bin cheekily labeled with a “blokes” section (for males) and a “sheila” section (for females). Once the sex of the fish is determined, we toss it in the proper bin. Each bin opens to a length board from which we measure all of the fish in the bin. For creatures other than our targeted pollock, we collect unsexed length and weight data from a smaller sample of individuals.

Pollock gonads: female ovaries

Pollock gonads: female ovaries

Pollock gonads: male testes

Pollock gonads: male testes


A spawning female! Note the ovaries, swollen with eggs.

Shipmate Spotlight: Interview with Darin Jones

Darin Jones, Scientist and Field Party Chief

Darin Jones, Research Fisheries Biologist, Field Party Chief (and my awesome blog editor)!

What is your position on the Oscar Dyson?
I am a Research Fisheries Biologist. I am also the field party chief in charge of the scientific team for leg 3 of our summer survey. I have been with the National Marine Fisheries Service for 8 years.

What training or education do you need for your position?
The ability to go to sea and not get seasick is key, and a solid marine biology education with plenty of math and statistics. I earned my undergraduate degree in marine biology from UNC at Wilmington, then a Masters in Fisheries Resources at the University of Idaho.

What do you enjoy the most about your work?
Being able to get out in the field and see the beautiful scenery of Alaska instead of being stuck behind a desk all the time. And, of course, meeting wonderful new people on each cruise.

Have you had much experience at sea?
After my undergraduate work, I was an observer for five years in Alaska on trawlers, longliners, and pot fishing boats and got lots of sea time. In New England I worked for about 4 years on a cod tagging program where we went out to Georges Bank and caught Atlantic Cod to tag and release.  I have also worked at fish hatcheries in California and South Carolina where we went to sea to collect brood stock. In my current position, I am at sea for about 3 months a year.

Where do you do most of your work aboard the ship? What do you do?
Most of my work is in “the Cave” (Acoustics Lab), where I monitor the acoustics equipment and analyze the data. When we are trawling, I go to the bridge to help guide the fishing operation. As field party chief, I direct all science operations, make daily decisions pertaining to the survey mission and its completion based on weather and time available, and I’m the liaison between the science party and the ship’s officers.

When did you know you wanted to pursue a marine career?
I have loved the ocean since I started surfing in high school. During college, I was looking for a career that would keep me near the ocean, and marine biology was a natural fit.

What are your hobbies?
I am a surfer and a woodworker, and I enjoy and playing the guitar.

What do you miss most while working at sea?
My family for sure. My own bed!

What is your favorite marine creature?
My porcupine pufferfish that I had during grad school; he had a personality and was always happy to see me.

Inside the Oscar Dyson: The Lounge

The lounge

The ship’s lounge

When you work hard at sea, you need a place to unwind and relax after a 12-hour shift. The lounge is right across the hall from my stateroom, and it is a great gathering place. It has comfy couches, a big bean bag chair, and a book library. The large television, like the televisions in the staterooms, has Direct TV with many channels. I have not watched television until this week when I began watching the last ever episodes of the Jon Stewart’s The Daily Show. The ship also has a large collection of DVDs.



Personal Log

We left Seward and headed up the coast to Prince William Sound. I can see why the region is known for its breathtaking wilderness scenery: mountains, islands, and fjords. The coast is lined with both dense spruce forest and tidewater glaciers. In fact, most of this area is part of the Chugach National Forest, the second largest National Forest in the United States. The sound’s largest port is Valdez, the terminus of the Trans-Alaska Oil Pipeline. In 1989, the oil tanker Exxon Valdez ran aground on Bligh Reef after it left Valdez, which resulted in a massive oil spill that caused environmental destruction and wildlife deaths.

Cruising through Prince William Sound

Cruising through Prince William Sound

My favorite part of working in the wet lab is when it’s time to sort the catch. We tilt the table, open the gate, and all the fish roll in on the conveyor belt. You never know what you will find among the pollock and rockfish. A lot of the time, there are krill and shrimp mixed in with the fish. Occasionally, there will be another big fish like a Pacific Cod (Gadus macrocephalus). A few times this week, there have been some very interesting baby creatures in our trawls. When sorting, you have to take care not to miss them!

My Alaskan fisheries adventure continues…


Here’s a big Pacific Cod…Photo by Emily Collins


And here’s some of the baby creatures found in our catches: (clockwise from top left) an Atka mackerel, an Alaska eelpout, Squid, and Snailfish.

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