NOAA Teacher At Sea: Thomas Ward Aboard NOAA Ship Miller Freeman
Mission: Fisheries Surveys Geographical Area of Cruise: Eastern Bering Sea Date: September 16, 2010
Question and Answer for the Teacher at Sea (NOAA)
Let’s jump right in, and not into the Bering Sea, it is too cold.
We have not seen any NOAA buoys, or at least I have not. NOAA does maintain numerous buoys but our mission aboard the Miller Freeman is strictly biological, juvenile flat fish to be specific. The types of little fish that we have caught and persevered for further study (remember the freezer) are; Yellowfin Sole, Pacific Halibut, Northern Rock Sole, Flathead Sole, Alaska Plaice, Arrowtooth Flounder, Kamchatka Flounder Greenland Turbot, and larvae of Long Head Dab. These fish that are being saved are relatively small, about 1-3 inches long, they are juveniles. The scientists are trying to determine the mechanism that controls the development of these juveniles into adults. I was also happy to learn that the scientists that are doing the sampling are also the same scientists that are going to be doing the work back in the lab. The identification of these youngsters seems to be effortless by the group of scientists I am working with, they really know their stuff. I have not seen too many ships here while we are out to sea. Last night I did see a light in the distance and assumed it was another ship but did not confirm it with the bridge. We do not fish to catch food for us on board. In fact there are so many regulations regarding fishing that we just focus on the mission and let the cooks in the galley do what they do, and let me tell you it is good. We often do get a glimpse of land, the pictures of the volcanoes on previous blogs are taken from our ship.
This video shows me measuring flat fish on the magnetic measuring board that I mentioned in an earlier blog. After imputing the species and other pertinent data, on a touch screen monitor, the fish is laid on the board and a device is touched to the board where the tail is. The length of the fish is recorded electronically. The fish that you see in the video are adults of the juveniles related to this FOCI Research Project and we still gather quantitative data on them. After we catalog them they are returned to the ocean where they have a very good chance of surviving. Keep those questions coming.
NOAA Teacher at Sea Richard Chewning Onboard NOAA Ship Oscar Dyson June 4 – 24, 2010
NOAA Ship Oscar Dyson Mission: Pollock Survey Geographical area of cruise: Gulf of Alaska (Kodiak) to eastern Bering Sea (Dutch Harbor) Date: June 13, 2010
Weather Data from the Bridge
Position: Eastern Bering Sea Time: 1530 Latitude: N 56 15.380 Longitude: W 164 14.010 Cloud Cover: Overcast with light spray Wind: 30 knots Temperature: 5.4 C Barometric Pressure: 1002.7 mbar
Science and Technology Log
Around 0940 Thursday morning we began our first summer 2010 pollock survey transect. Researchers have been conducting acoustic pollock trawl surveys since 1979 and bottom trawl surveys since the1950’s. The 31 transects in this year’s survey run roughly north south and progress from the eastern Bering Sea across to Russian waters in the western Bering Sea. The transect lines range in length from 60 to 270 nautical miles and are spaced 20 nautical miles apart. A nautical mile is slightly longer than a standard mile and is useful for navigating charts (maps used at sea). Only surveying during daylight hours, the Dyson will continue to run these transects till the beginning of August. A transect is a path (usually a straight line) during which the number of occurrences of an observable fact are counted (such as the abundance of pollock).
The beginning transect was marked by the launching of an expendable bathythermograph (XBT) probe. While the name might seem long and somewhat complicated sounding at first, the instrument and data being recorded are actually quite straightforward. Expendable refers to the fact that the probe is not recovered after being deployed. How is the data sent back to the Dyson you ask? Two long thin copper wires uncoil from the launcher and probe allowing data transfer back to the Dyson. The wires are broken by hand once the probe has reached the bottom. The rest of the story is revealed by subdividing the word ‘bathythermograph’ and defining its parts. ‘Bathy’ is a prefix that means deep or at depth. ‘Thermo’ is another prefix that refers to heat or temperature. Finally the word ‘graph’ means to draw a relationship between multiple variables (such as depth of the water and temperature). So an expendable bathythermograph is a disposable probe that profiles the temperature from the surface to the sea floor.
XBT probe and launcher
The XBT is a very helpful tool that enables the scientists onboard the Dyson to gather temperature data while on the move. Being able to capture this data without slowing down and stopping is a big time saver. Bringing a ship to a stop on the water takes much more time than stopping a car on the highway, and deploying a reusable instrument to the bottom and back takes even more time, manpower, and resources. Temperature data allows fish biologists to better understand how water temperature and the abundance of pollock and their food supply are related.
Darin deploying XBT
Later that afternoon, we also performed our first Tucker trawl. The Tucker trawl is a cleverly designed system of three nets that allows for three discrete (separate) samples during a single deployment. The Tucker trawl is designed to catch the zooplankton (animal-like plankton) that pollock eat such as euphausiids. This net allows researchers to study the differences of zooplankton distribution at various layers in the water.
Deploying the Tucker trawlTucker trawl messenger
To catch these small organisms, the net needs to a have very small openings. In fact, the openings in the net are only half a millimeter in width or roughly 1/3 the thickness of a dime! The three nets are attached to a metal frame mounted on metal skis that resembles a backwards dog sled. These skis allow the sled to slide along the seafloor and avoid snagging any obstructions. The Tucker trawl is initially deployed with one net open. The first net is closed and the next net is opened using a heavy brass messenger sent down the wire connecting the Tucker trawl to the Dyson. The messenger is attached to the wire cable at the surface and allowed to slide down the cable to the net being towed in the water. The impact of the messenger triggers a spring in a latch that closes one net and opens another net. The second net is closed and the third net is opened in the same fashion. Samples are taken at the surface, at the bottom, and evenly from the seafloor all the way to the surface. Attached to the sled are sensors to record temperature and depth, the flow of water passing through the net, and the time the net spends on the bottom. The catch is collected at the end of the net in a removable cod end jar. Any jellyfish are removed from the catch, identified, and measured. The remaining zooplankton is weighed, and a small subsample is saved and preserved for later identification.
Richard sending messenger down to the Tucker trawlEuphausiidHyperiid amphipod
Personal Log
At sea, a person can easily lose track of time and even forget the day of the week as work aboard the Oscar Dyson continues uninterrupted seven days a week. I was reminded that today was Saturday by a special meal served by the galley. Rick and Floyd prepared a delicious dinner of real Alaskan king crab, prime rib, baked potatoes, vegetables, and fresh baked bread. This was a real treat (along with the cookies and cream ice cream, always a fan favorite) for the crew. There was plenty to go around, and all were well satisfied.
This was actually not my first encounter with king crab on this cruise. The day before, we had the unprecedented surprise of catching a red king crab with the Tucker trawl during the bottom net deployment. To the best of the knowledge of all the scientists onboard, this had never happened before. You might remember that the Tucker trawl is designed to catch zooplankton, which are typically small in size. This unlucky crab was so large she didn’t even fit in the cod end collection jar at the end of the net. In the end the crab was lucky as we opted to release her after recording her weight and species as we already had enough crab in the freezer for dinner the following night!
Richard holding red king crabDinner! Lucky for her, the crab Richard’s holding was released back to the sea!
Leisure Activities
Time spent not working onboard the Dyson can be considered among a person’s most precious possessions. Working long hours, the NOAA Corps officers, visiting scientists, and crew aboard the Dyson usually only have a few hours of time before starting their next scheduled watch or shift. Sleeping is often the first order of business on a person’s to do list. Whether you take only a short nap or can sleep for several blissful hours, time in one’s rack (bed) is essential for a productive, happy, and safe crew. Often one’s sleep schedule will necessitate missing a meal but the rest gained seems well worth the trade off. A very nice service offered by the galley is making and setting aside a plate for those crew members missing a meal if requested.
Other down time activities include reading, listening to music, and working out. The Dyson also has an impressive movie collection (including many recent titles not yet released on DVD) that is administered by the Department of the Navy. New titles are added monthly. The Dyson has a very comfortable lounge for watching movies that also includes a wide selection of magazines and books. Keeping connected with the outside world is also very important while at sea. With relative reliability, people can access the internet to answer emails, pay bills online, and surf the web for news and can call friends and family back home using the satellite phone.
