Cristina Veresan, Lights, Camera, Ocean! August 13, 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 13, 2015

Data from the Bridge:
Latitude: 59° 18.31’N
Longitude: 141° 36.22’W
Sky: Overcast
Visibility: 10 miles
Wind Direction: 358
Wind speed: 8 knots
Sea Wave Height: < 1 feet
Swell Wave: 2-3 feet
Sea Water Temperature: 16.2°C
Dry Temperature: 15°C

Science and Technology Log

When my shift begins at 4am, I often get to participate in a few “camera drops” before the sun comes up and we begin sailing our transect lines looking for fish. We are conducting the “camera drops” on a grid of 5 km squares provided by the Alaska Fisheries Science Center bottom trawl survey that shows whether the seafloor across the Gulf of Alaska is “trawlable” or “untrawlable” based on several criteria to that survey. The DropCam footage, used in conjunction with a multi-beam echosounder, helps verify the “trawlability” designation and also helps identify and measure fish seen with the echosounder.


The Drop Camera being deployed

The DropCam is made up of strobe lights and two cameras, one color and one black and white, contained in a steel frame. The cameras shoot in stereo, calibrated so scientists can get measurements from rocks, fish, and anything else on the images. When the ship is stopped, the DropCam can be deployed on a hydrowire by the deck crew and Survey Tech. In the Chem Lab, the wire can be moved up and down by a joystick connected to a winch on deck while the DropCam images are being viewed on a computer monitor. The ship drifts with  the current so the camera moves over the seafloor at about a knot, but you still have to “drive” with the joystick to move it up and down, keeping close to the bottom while avoiding obstacles. The bottom time is 15 minutes for each drop. It’s fun to watch the footage in real-time, and often we see really cool creatures as we explore the ocean floor! The images from the DropCam are later analyzed to identify and length fish species, count number of individual fish, and classify substrate type.


Emily “drives” the camera from the Chem Lab as the sun begins to rise


DropCam images (clockwise from top left) a skate, brittle stars, a cruising halibut, two rockfish in rocky habitat

Technology enables scientists to collect physical oceanographic data as well. The Expendable Bathythermograph (XBT) is a probe that is dropped from a ship and measures the temperature as it falls through the water column. The depth is calculated by a known fall rate. A very thin copper wire transmits the data to the ship where it is recorded in real-time for later analysis. You launch the probe from a hand-held plastic launcher tube; after pulling out the pin, the probe slides out the tube. We also use a Conductivity Temperature Depth (CTD) aboard the Oscar Dyson; a CTD is an electronic device used by oceanographers to measure salinity through conductivity, as well as temperature and pressure. The CTD’s sensors are mounted on a steel frame and can also include sensors for oxygen, fluorescence and collecting bottles for water samples. However, to deploy a CTD, the ship must be stopped and the heavy CTD carousel lowered on a hydrowire. The hand-held XBT does not require the ship to slow down or otherwise interfere with normal operations. We launch XBT’s twice a day on our survey to monitor water temperatures for use with the multi beam echosounder.


Cristina launching the XBT probe Photo by Alyssa Pourmonir


Survey Tech Alyssa servicing the CTD carousel














Shipmate Spotlight: An Interview with Ensign Benjamin Kaiser


Ensign Benjamin Kaiser, NOAA Corps

Tell me a little more about the NOAA Corps?
We facilitate NOAA scientific operations aboard NOAA vessels like hydrographic work making charts, fisheries data collection, and oceanographic research.

What do you do up on the bridge?
I am a Junior Officer of the Deck (JOOD), so when I am on the bridge driving the ship, I am accompanied by an Officer of the Deck (OOD). I am on my way to becoming an OOD. For that you need 120 days at sea, a detailed workbook completed, and the Commanding Officer’s approval.

What education or training is required for your position?
I have an undergraduate degree in Marine Science from Boston University. My training for NOAA Corps was 19 weeks at the Coast Guard Academy in New London, Connecticut– essentially going through Coast Guard Officer Candidate School.

What motivated you to join the NOAA Corps?
A friend of mine was an observer on a fisheries boat, and she told me about the NOAA Corps. When I was in high school and college, I didn’t know it was an option. We’re a small service, so recruiting is limited; there’s approximately 320 officers in the NOAA Corps.

What do you enjoy the most about your work?
I love not being in an office all the time. In the NOAA Corps, the expectation is two years at sea and then a land assignment. The flexibility appeals to me because I don’t want to be pigeonholed into one thing. There are so many opportunities to learn new skills. Like, this year I got advanced dive training for Nitrox and dry suit. I don’t have any regrets about this career path.

What is the most challenging part of your work?
There’s a steep learning curve. At this stage, I have to be like a sponge and take everything in and there’s so much to learn. That, and just getting used to shipboard life. It is difficult to find time to work out and the days are long.

What are your duties aboard the Oscar Dyson?
I am on duty 12pm to midnight, rotating between working on the bridge and other duties. I am the ship’s Safety Officer, so I help make sure the vessel is safely operating and coordinate drills with the Commanding Officer. I am also the Training Officer, so I have to arrange the officers’ and crew members’ training schedules. I am also in charge of morale/wellness, ship’s store, keys, radios, and inspections, to name a few.

When did you know you wanted to pursue a marine career?
I grew up in Rhode Island and was an ocean kid. I loved sailing and swimming, and I always knew I would have an ocean-related career.

How would a student who wanted to join the NOAA Corps need to prepare?

Students would need an undergraduate degree from a college or university, preferably in a STEM field. Students could also graduate from a Maritime Academy. When they go to Officer Candidate School, they need to be prepared for a tough first week with people yelling at them. Then there’s long days of working out, nautical science class, drill work, homework, and lights out by 10pm!

What are your hobbies?
I enjoy rock climbing, competitive swimming, hiking, and sailing.

What do you miss most while working at sea?
There’s no rock climbing!

What is your favorite marine creature?
Sailfish because they are fast and cool.

Inside the Oscar Dyson: The Chem Lab


This lab is called the Chem Lab (short for Chemical). For our survey, we don’t have that many chemicals, but it is a dry lab with counters for workspace when needed. This room is adjacent to the wet lab through a watertight door, so in between trawls, Emily and I spend a lot of time here.  In the Chem Lab, we charge batteries for the CamTrawl and the DropCam. There are also two computer stations for downloading data, AutoLength analysis, and any other work (like blogging!). There is a window port to the Hero Deck, where the CTD and DropCam are deployed from. In the fume hood, we store Methot net samples in bottles of formalin. There is a microscope for viewing samples. Note the rolling chairs have their wheels removed and there are tie-downs on cases so they are safer at sea. Major cribbage tournaments are also played in this room!

Personal Log

It has been so calm on this cruise, but I have to say that I was looking forward to some bigger waves! Well, Sunday night to yesterday afternoon we experienced some rain and rough seas due to a nearby storm. For a while the ship would do big rolling motions and then a quick lurchy crash. Sea waves were about 2 feet in height, but the swell waves were over 5 feet at times. When I was moving about the ship, I’d have to keep a hand on a rail or something else secured. In the wet lab while I was working, I would lean against the counter and keep my feet spread apart for better balance.


Seas picked up and the ship was rocking and rolling!

Remember the Methot net? It is the smaller net used to catch macroplankton. We deployed one this week and once it came out of the water, it was rinsed and the codend was unscrewed. When we got the codend into the wet lab, we realized it was exclusively krill!


The Methot net is deployed by the Survey Tech and deck crew members



Krill are  small crustaceans that are found in all the world’s oceans. Krill eat plant plankton (phytoplankton), so they are near the bottom of many marine food chains and fed on by creatures varying from fish like pollock to baleen whales like humpbacks. They are not so small that you need a microscope to see them, but they are tiny. We took a subsample and preserved it and then another subsample to count individuals…there were over 800 krill in just that one scoop! Luckily, we had them spread out on a board and made piles of ten so we did not lose count. It was tedious work moving individual krill with the forceps! I much prefer counting big things.

I love it when there is diversity among the catch from the AWT trawls. And, we caught some very memorable and unique fish this week.  First was a beautiful Shortraker Rockfish (Sebastes borealis). Remember, like the Pacific Ocean Perch, its eyes bulge when its brought up from depth. The Shortraker Rockfish is an open-water, demersal species and can be one of the longest lived of all fish. There have  been huge individuals caught in Alaskan waters that are over 100 years old. This fish was not particularly big for a Shortraker, but I was impressed at its size. It was probably my age.


Holding a Shortraker Rockfish. Photo by Emily Collins


Smooth Lumpsucker fish: so ugly it’s cute?! Photo by Mackenzie Wilson

We also caught a Smooth Lumpsucker (Aptocyclus ventricosus). It was inflated because it was brought up from depth, a form of barotrauma. This scaleless fish got its name for being shaped like a “lump” and having an adhesive disc-shaped “sucker.” The “sucker,” modified pelvic fins, are located ventrally and used to adhere to substrate. These pelagic fish are exclusively found in cold waters of the Arctic, North Atlantic, and North Pacific. The lumpsucker fish, and its roe (eggs) are considered delicacies in Iceland and some other countries.


You can see the “sucker” on the bottom of its body. Photo by Mackenzie Wilson

Pollock are pretty slimy and they have tiny scales, so when we process them, everything gets covered with a kind of speckled grey ooze. However, when we trawled the other day and got a haul that was almost entirely Pacific herring (Clupea pallasii), I was amazed at their scales. For small fish, the herring had scales that were quite large and glistened like silvery sequins. The herring’s backs are an iridescent greenish-blue, and they have silver sides and bellies. The silver color comes from embedded guanine crystals, leading to an effective camouflage phenomenon in open water.

As this last week comes to a close, I am not ready to say goodbye…


Herring scales are nature’s sequins

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