Tag: beam trawl

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Kimberly Gogan: Night Crew Oceanography! More than just a Bongo! April 29, 2014

NOAA Teacher at Sea
Kim Gogan
Aboard NOAA Ship Gordon Gunter
 April 7 – May 1, 2014

Mission: AMAPPS & Turtle Abundance Survey, Ecosystem Monitoring
Geographical area of cruise:  North Atlantic Ocean
Date: April 29, 2014

Weather Data from the Bridge
Air Temp: 15.5  Degrees Celsius
ind Speed: 7 – 12 Knots
Water Temp: 8.8  Degrees Celsius
Water Depth: 10 Meters

Science and Technology Log

As I mentioned in my previous blogs, there are many layers of science that are happening simultaneously that support the AMAPPS project (see April 9th blog). One of these layers is monitoring the ecosystem with oceanography. In the April 9th blog I explained all about the Bongo Nets, and in April 15th blog I explained about the VPR and it’s plankton picture data. While the rest of the ship slept, the night time oceanography team – Betsy Broughton (scientist from NEFSC in Woods Hole), John Rosendale (lab technician from NOAA Fisheries Howard Labratory in Sandy Hook) and Brian Dennis (volunteer) were busy conducting Benthic science with the Beam Trawl and Van Veen Grab Sampler.

Although  this equipment was not used every night, I was lucky enough to have stayed up some of the night to see these two in action. The Benthic Zone, in a body of water, like the ocean refers to the very bottom of that aquatic ecosystem. The night time science team use a Beam Trawl or a bottom fishing net that is towed along the bottom of the ocean to take a sample of the organisms that live there. The Beam Trawl is attached to a winch that is on the stern of the boat, that one is much larger than the winch that is used to lower the Bongo Nets. The trawl is lowered down until it touches the bottom and then towed along the bottom picking up whatever is in its path. The trawl is then brought to the surface and the sample is sorted in the wet lab and preserved in formaldehyde just like the other samples. The Van Veen Grab Sampler is lowered into the water by the same smaller winch that is used for the Bongo Nets along the port side of the ship. The grab is rigged so that when it touches the bottom of the ocean, two arms open up and grab a large sample of the sediment at the bottom of the ocean. To me it looked just like the suffer muck I know as “clam flats.” Once the Van Veen Grab is brought up to the surface, the arms of the grab are released and the sediment is dropped into a bucket. From there the soil is washed over and over using several sized sieves until all of the muck is washed away and just the organisms, shells and assorted bottom treasures are left. This sample, once cleaned, is also brought back to the chemistry lab for processing in formaldehyde.  The scientists worked at a much faster pace to get all the sediment removed and the  samples processed. It was fun to be able to watch and help out.

Betsy teaching me how to run the computer software for the CTD.
Betsy teaching me how to run the computer software for the CTD.

Personal Log:

For most of the trip, my “assigned” task has been to work with Jerry Prezioso as the day Oceanography team. Jerry and I are in charge of the mid-day Bongo Nets (see April 9th blog). Sometimes we are up early and timing is such that our morning Bongo Net overlapped with night crew’s scheduled time. Sometimes they would start the morning Bongo and Jerry and I would take over and finish the work, or we would just all work together to get it done twice as fast.  Since there were more people to help in the morning, Betsy Broughton (see April 15th blog) was available to help teach me how to run the computer software that was attached to the Bongo called a CTD Sensor.

The graph on the computer software of the Conductivity, Temperature and density data the CTD collects as the Bongo drops to it's lowest depth.
The graph on the computer software of the Conductivity, Temperature and density data the CTD collects as the Bongo drops to its lowest depth.

CTD stands for Conductivity, Temperature and Depth and it sits above the Bongo Net collecting this data that it sends back to the computers. Generally one scientist is in charge of running the software that turns on the CTD and gets it to start collecting data as it is dropped down into the deep water. The person on the computer is in charge of knowing how deep the Bongo Net should go and telling the winch operator when to pull the Bongo Net back up to the surface. They are also responsible for letting the NOAA Corps officer on the Bridge know when the equipment is ready and telling the winch operator the speed at which the Bongo should be dropped. If this information is not relayed correctly the Bongo Net could go crashing into the bottom of the ocean. It took a couple of days of Betsy overseeing what I was doing, but in no time at all, Jerry felt confident enough in me to leave me at the helm and let me run the software on my own. From net washer to computer software operator, I was moving up!

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Thomas Ward, September 18, 2010

NOAA Teacher At Sea: Thomas Ward
Aboard NOAA Ship Miller Freeman

Mission: Fisheries Surveys
Geographical Area of Cruise: Eastern Bering Sea
Date: September 18, 2010

More Questions, Cool

NOAA Ship Miller Freeman
NOAA Ship Miller Freeman

In this blog I will make an attempt to answer more of the questions I have been receiving.

The Ship, The Miller Freeman.  She was commissioned in 1967, is 215 feet long and was built to be a scientific research vessel. http://www.moc.noaa.gov/mf/

Once we catch the fish, which is only done using the beam trawl, the winch pulls them on board.  Because of the size of the net and the limited time that we are pulling it, the catch is not too large.  The catch can then be lifted by hand into the  kiddie pool and sorted.  If the catch happens to be a little heavy, one of the cranes picks it up and dumps it onto the sorting table for all of us to gather around and do our thing.  The juveniles that are of importance to this study are bagged and labeled, then frozen.  They will be studied back at the lab in Seattle, at the Alaska Fisheries Science Center, AFSC.

Each of the three methods used have a different purpose and the only method that actually catches fish is the beam trawl.

The different species are sorted, measured and weighed.  The juveniles are kept and the larger ones are weighed, counted, and returned to the sea.  Last night we caught over 100 yellowfin sole in one haul.

The gantry, used to haul the trawl and the sled onto the stern.

The research study that I am part of, the FOCI study, is a very active group.  There is currently a group in the Arctic and another cruise just ended before we started.

There are 24 crew members on board and 10 scientists.

For me the down time has been mainly in front of the computer, doing this blog and other school work.  There is a lounge with a TV. movies and TV series box sets available for people to watch.  The catalog of movies that they have is extensive.  There is also a small exercise room and a small library.  Of course there are computers around the ship which have access to the internet.

We have not found any “new or different kind of species”  There is occasion though when sorting through the beam trawl haul an usual critter gets spotted, the scientist get very excited.  For that matter, everyone else does too. It is similar to saying that laughter is contagious, so is the excitement of finding something that is rare.

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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.