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: Thomas Ward Aboard NOAA Ship Miller Freeman
Mission: Fisheries Surveys Geographical Area of Cruise: Eastern Bering Sea Date: September 14, 2010
After the Catch
This segment is devoted to what happens to the organic material we acquire once we get it on board. The benthic sled has a very fine mesh net, plankton net, attached to it and has a container at the end of it, a cod end. This is where the epibenthic invertebrates end up. Once the gear is on board the crew washes down the net with sea water to get any invertebrates to wash down into the cod end. It took getting used to that the garden hoses around deck have salt water in them. Growing up all your life using hoses outside with fresh water in them and then being on board here and getting an occasional spray to the face and it is salt water is a reminder of where I am really at. Any how, the sample in the cod end is put into a jar and preserved in a buffered Formaldehyde solution.
The beam trawl is used to study settlement and nursery areas for age-0 flatfishes. This is probably what most people would associate with net fishing. When the haul comes up there is an assortment of organisms in it. The catch is dumped in to a kiddie pool and we gather around it and start to sort, flopping flat fish and all.
These pictures are a good example of what we are doing. Remember that we are primarily studying juvenile species and what is the primary mechanism in nature that helps these little ones become adults.
The fascinating thing is the differences in the catches per location. Once the fish that are the focus of this study have been sorted, they are measured, weighted, bagged and frozen. They are carefully labeled and frozen at a temperature of -80 degrees Celsius in the rough lab. After 24 hours they can be moved to a “warmer” freezer, -20 degrees Fahrenheit, which is in the slime lab.
The catch comes on board at the stern of the ship, which is the open rear of the ship where the majority of the heavy equipment is, like cranes and such. After the catch is sorted it is brought into the wet lab for measuring, weighing and bagging. The measuring board that we have in this lab is very cool. There are touch screen monitors that are set up where the species that we are concerned with is selected. The correct species is chosen and the fish are individually placed on this electronic board. The scientist then puts the individual fish nose at one end and takes a hand held device and places it near the tail. The machine makes a funky sound and the length of the fish is recorded electronically. Very cool, quick and convenient. With a good team working this station, a fish can be measured about one every second, pretty efficient.
The benthic grab is specifically used to sample subtidal soft-bottom benthic macroinvertebrates. This is done to determine what is in the substrate. This is the layer just below the surface. This is what the juvenile flat fish feed on. When determining what causes a population’s numbers to fluctuate it is important to study what it eats
The jellyfish above are very cool but not of much interest to this study. The sole above is one of the larger flat fish that we have caught. We do catalog them but we do not save them for future study. The interesting thing that I want to point out about the picture of the sole is the location of their eyes. Both eyes are on the same side of their body. These fish lay on the bottom and wait for prey to swim by. It is and was a huge evolutionary advantage for them to have both eyes on one side of their body.
Life on board ship is a very different experience. Yesterday was proof of that for me when the seas turned to 7-9 feet and my body could not handle it. The crew amazed me because word of my illness spread around and many pepole have been asking me how I have been feeling today. It is what I would call a concerened, caring, working family. At first coming aboard, getting around the ship was very confusing. There are numerous stairways that lead to different decks and there is a very similar look to things on the ship. I am getting used to it and to stepping through a bulkhead to walk through the ship. These bulkhead doors are water tight doors that are closed to protect parts of the ship in case of an accident. The sleeping quarters are sufficent. I am in a 4 man room with 3 other guys, with a bathroom attached to it. I have my own personal locker which contains my personal effects and my life jacket and survival suit. On the door the crew placed a billet which is a document that is specifally designed for the individual. Among other things it gives my lifeboat station which we would have to muster to if an emergency occurred. We have practiced this drill and hope that it does not become real any time soon. I am in a lower bunk. The noise and the motion of the ship is the hardest thing to get used to. I occasionally sleep with ear plugs but that does not seem to help much. A solid, uninterupted 8 hours of sleep will be very much appreciated when I return. But, as any one that knows me knows that I can definately catch up on sleep by napping, and just about anywhere.
Remember that if you have any questions you can ask through this blog. I believe you have to sign up for a Google account but it seems to do anything on the web these days you either have to register or sign on in some manner. Just click the commnets icon towards the bottom of the blog and follow the prompts, it is not too cumbersome. I hope you have enjoyed reading this and I am almost done describing the science so I hope the questions start rolling in. Hope for flat seas for me.
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 18, 2010
Weather Data from the Bridge
Position: Bering Sea, north of Dutch Harbor Time: 1600 hours Latitude: N 55 06.120 Longitude: W 166 33.450 Cloud Cover: Mostly cloudy Wind: 10 knots from the west Temperature: 7.1 C Barometric Pressure: 1010.8
Science and Technology Log
In order to manage a public resource such as pollock, fisheries managers must develop a stock assessment. A stock assessment is a big picture overview of a certain population of fish. Fisheries managers use stock assessments to determine opening and closing dates for fishing seasons, catch limits (the number of fish that can be caught by a particular fisherman or boat), and the total allowable catch for the season. Stock assessments are developed from a combination of fishery dependant and independent data. Fishery dependant data includes catch records from commercial fishing boats and reports from processors dockside that prepare and package the fish for market. Combined with this information is fishery independent data. This information is gathered from sources not involved with commercial fishing.
The Dyson’s acoustic trawl survey is one of the primary sources of fishery independent data for the pollock stock assessment. The Dyson’s transducers provide a wealth of acoustic data from each transect. These acoustic returns must first be identified or deciphered before being used in the stock assessment. Just like you need a key to decode the symbols on a road map or need a scale to interpret the colors on a weather map, the acoustic returns also need to be referenced with actual pollock specimens collected by trawling. By matching up the characteristics of the fish caught in the trawl with their acoustic returns, researchers can interpret all the acoustic data from the entire survey area.
Pollock specimens are collected with Aleutian wing trawls, or AWTs for short. An Aleutian wing trawl is a single large net deployed off the stern of the Dyson. Large metal fishbuster doors are used to open the mouth of the net in the water. The catch is collected in a bag located at the end of the net called the cod end. The cod end’s mesh size prevents anything larger than 0.5 inches from escaping. Once the net is hauled back on deck, the cod end is emptied in the wet lab, and the entire catch is sorted. Fish are identified, counted, weighed, and measured. The gender and maturity of a subsample of pollock are also recorded. Stomachs are collected to determine what the pollock are eating. Finally, otoliths, the ear bones of fish, are collected. Just like counting the rings of a tree, researchers will count the number of rings in the otolith to determine the age of the pollock. Notable bycatch (fish that were not targeted) include eulachon, arrowtooth flounder, Pacific cod, sturgeon poacher, and yellowfin sole. Misha told me Russians used to dry out eulachon whole and use them as candles because of their high oil content. In fact I learned that one of common names in the US for eulachon is candlefish!
Why gather so much information on a single species of fish like pollock? Fisheries managers are responsible for the sustainable use of public resources. Without careful monitoring, fishing pressure, natural predation, and disease might remove pollock from the population faster than they can replace themselves. There is great demand for pollock both commercially and in the Bering Sea ecosystem. Walleye pollock is the largest US fishery by volume and third largest by value. Annual US catches can average 2.5 billion pounds. Pollock is also an important food source for Stellar sea lion, other marine mammals, birds, and other fish.
On Thursday, I had the pleasure of joining two members of the deck crew, Joel Kellogg and Glen Whitney, to pick up a new addition of the science party in Dutch Harbor. Mike Sigler, a fish biologist with NOAA, is a project leader and principal investigator with the North Pacific Research Board’s Bering Sea Integrated Ecosystem Research Program (BSIERP). He is joining the Dyson for the last week of our survey. BSIERP is a six year long collaborative study with the National Science Foundation’s Bering Ecosystem Study (BEST). More than a hundred scientists from these two groups are investigating the organisms and physical forces that make up and influence life in the Bering Sea ecosystem.
To pick up Mike, the Dyson launched the Peggy D. Named for wife of Oscar Dyson, the Peggy D. is a small power boat used to ferry people to and from shore. Peggy Dyson is a famous Alaskan in her own right, serving as a National Weather Service ship to shore weather broadcaster. Her voice brought vital information and reassurance to Alaskan fisherman. She diligently performed these duties twice a day, seven days a week for 25 years. I really enjoyed having the opportunity to see the Dyson from the water as my only vantage point for the last two weeks has been from the Dyson looking out. I was surprised how quickly the Dyson shrunk on the horizon as we sped away and traveled into Dutch Harbor. Dutch Harbor felt like a true frontier town. The vehicles seemed to reflect the character of the town. While looking rough and weathered on the outside, the beat-up cars and trucks of Dutch Harbor revealed a resilience and gritty determination to keep moving forward and press on against an unforgiving environment. I loved hearing the cry of the bald eagles that were spotted everywhere you looked. While I enjoyed having solid ground under my feet for a few short minutes, I appreciated the sense of familiarity and belonging I felt upon returning to the Dyson.
Scute, the Georgia Sea Turtle Center Mascot, was spotted visiting the Bering Sea today! Scute, a loggerhead sea turtle, travels the world promoting awareness of sea turtles. We know Scute was only visiting the Bering Sea as these waters are too cold for loggerhead sea turtles. Loggerhead sea turtles are the most abundant sea turtles in US coastal waters. Scute’s home is the Georgia Sea Turtle Center (GSTC) located on Jekyll Island, Georgia. The GSTC is a research, rehabilitation, and education center dedicated to helping sea turtles along the GA coast and around the world. Sea turtles released from the GSTC will often have a satellite transmitter attached to their shell just like Scute. The transmitters allow researchers to track their movements at sea. Only one of the seven species of sea turtles found worldwide can survive this far north – the leatherback sea turtle. The leatherback sea turtle is the largest species of sea turtle reaching six and a half feet in length and weighing as much as 2000 pounds! Leatherbacks have several adaptations such as high oil content in their large bodies that help them tolerate the cold waters of the southern Bering Sea. Leatherback sea turtles feed on jellyfish and can dive to great depths because the protection provided by their leathery shell (a hard shell would crack under the high pressure of the water). For more information about Scute and sea turtles, check out the GSTC website at http://www.georgiaseaturtlecenter.org !