Tuesday, October 5, 2010

NOAA Teacher at Sea: Barbara Koch
NOAA Ship Henry B. Bigelow
Mission: Autumn Bottom Trawl Survey Leg II
Geographical area of cruise: Southern New England
Date: Tuesday, October 5, 2010

Weather from the Bridge
Latitude 40.63
Longitude -72.92
Speed 4.80 kts
Course 293.00
Wind Speed 19.13 kts
Wind Dir. 139.69 º
Surf. Water Temp. 18.76 ºC
Surf. Water Sal. 31.62 PSU
Air Temperature 16.20 ºC
Relative Humidity 89.00%
Barometric Pres. 101.44 mb
Water Depth 28.52 m
Cruise Start Date 10/2/2010

Science and Technology Log

In addition to collecting data about fish species in the Southern New England Atlantic Ocean, NOAA Ship Henry B. Bigelow is also collecting information about the ocean's climate and plankton numbers. Plankton refers to microscopic plants (phytoplankton), animals (zooplankton), decomposers (bacterioplankton), and the fish eggs and larvae of larger fish (ichthyoplankton). Plankton forms the base of the ocean food web. Phytoplankton is the food source for zooplankton, which in turn is the food source for larger fish. Water salinity and termperature (climate) are directly related to the production of plankton. A change in climate can cause a decrease in the production of plankton, therefore, less food for developing fish species. Low numbers of fish at the bottom of the food web means less food for fish at the top of the food web.

Plankton samples are taken at random trawl stations during the cruise. I had the opportunity to observe and assist the Senior Survey Technician, Jim Burkitt, during one sampling. Burkitt uses a Bongo Paired Zooplankton net system, which consists of two stainless steel cylinders with instruments that measure water flow, and two cone-shaped, fine mesh nets attached. The nets are lowered into the ocean and dragged alongside the ship for a specified amount of time, and at all levels of the ocean column. Burkitt monitors the location of the nets via computer during the sampling to ensure that the nets do not touch the ocean floor, thus gathering sediment instead of plankton.

The crew retrieves the nets at the end of the sampling period and places it on the deck of the ship. Once the nets are back on deck, we rinse the plankton from the top to the narrow, tied end of the nets by spraying the nets from the top towards the bottom.




When the catch is located at the bottom of the nets, we untie the bottom and continue rinsing the sample into metal strainers. The top strainer has a large mesh screen to trap jelly fish and other organisms trapped in the net and to allow the smaller plankton to fall through to the lower strainer, which has a very small mesh screen used to collect the plankton sample. Here is what the sample looked like.

Finally, we carry the samples into the lab where we rinse the plankton into jars, add formaldehyde as a preservative, and seal the jars. The jars will be taken to the lab in Woods Hole for further analysis.





Personal Log

Even though many of our towing days were lost to gale force winds, we did end the cruise by catching some interesting species. First, was the Northern Stargazer (Astroscopus guttatus). The Northern Stargazer is found in shallow waters along the eastern seaboard from North Carolina to New York. It has a large head, small eyes on top of its head, and a large upward turned mouth. The Northern Stargazer buries itself in the sand on the ocean floor and waits for prey to swim by. Northern Stargazers also have an electrical organ around the eyes that can give us a jolt if we touch it.

Another interesting catch was the Armored Searobin (Peristedion miniatum). This species is bright crimson and is totally covered with bony plates. It can grow to be 13-14 inches long. It is found in the warm waters along the outer edge of the continental shelf in waters from Georges Bank off of Cape Cod, Massachusetts all the way down the Atlantic to Charleston, South Carolina.


We also caught Monkfish or Goosefish (Lophius americanus). This fish is found along the eastern seaboard of the United States from Grand Bank down to Cape Hatteras, North Carolina. Monkfish live on the bottom of the ocean in sand, mud and shell habitats, and feed on whatever prey is abundant. The meat is said to taste a lot like lobster tail, and therefore is often referred to as "poor man's lobster."



Our most exciting catch came when we hauled in 212 striped sea bass! Striped bass occur along the Atlantic coast from the St. Lawrence River in Canada all the way down to Florida. They live near the coast, in bays and tidal rivers. Striped bass have been very important to the United States fishing industry for centuries. The largest one we caught was 103 cm long and weighed 11.26 kg!

I thoroughly enjoyed my time working and learning during the second leg of the Autumn Bottom Trawl Survey cruise. It was a great opportunity to see research at work in a real world setting, and I'm sure my students will benefit from everything I've experienced. I want to thank the scientists from the Northeast Fisheries Science Center (NEFSC), the NOAA Teacher at Sea Program, and the crew aboard NOAA Ship Henry B. Bigelow for allowing me to be a part of your lives for twelve days. If any of you teachers out there are interested in applying to the Teacher at Sea Program, I highly recommend it. Check out their website at http://teacheratsea.noaa.gov/.