Thomas Ward, September 14, 2010

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.
Sorting

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.

Keepers

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

Jellyfish

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.

Yellowfin Sole

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.

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