NOAA Teacher at Sea
Nicolle von der Heyde
Onboard NOAA Ship Pisces
June 14 – July 2, 2010
Nicolle von der Heyde
NOAA Ship Pisces
Mission: SEAMAP Reef Fish Survey
Geographical Area of Cruise: Gulf of Mexico
Dates: Wednesday, June 23
Weather Data from the Bridge
Time: 1000 hours (10 am)
Position: latitude = 27°51 N longitude = 093º 51 W
Present Weather: 7/8 cloudy (cumulus/cirrus clouds)
Visibility: 10 nautical miles
Wind Direction: SSE Wind Speed: 8 knots
Wave Height: > 1 foot
Sea Water Temp: 31°C
Air Temperature: dry bulb = 31.4°C, wet bulb = 28°C
Science and Technology Log
Because of the oil spill in the Gulf of Mexico, most of the fish we are catching in the Chevron Trap or Bandit Reel is being weighed, measured, and frozen for the National Seafood Inspection Laboratory (NSIL) to be tested for oil or toxin contamination. After the NSIL completes its testing, the fish are sent back to the NOAA Pascagoula Laboratory where the scientists determine the sex of the fish and remove the otolith, or ear bone, which can be analyzed to determine its age. The otoliths are sliced very thin and examined under a microscope. Rings can be seen that help the scientists age the fish, similar to reading tree rings to determine the age of a tree. Age data is analyzed to contribute to the fishery-independent stock assessments which help determine the health of the fish population and how many can be taken out of the water. This also helps establish the size restriction of fish for the commercial and recreational fishing industry.
Occasionally, the fish trap will catch more than 10 fish at a time. If this happens, the first 10 fish are frozen for NSIL. Any remaining fish are dissected on board the ship to determine their sex and their otoliths are removed and placed in a labeled envelope for later analysis. The picture above shows the otoliths taken out of a red snapper.
The video footage taken at each station will also be analyzed in depth back at the NOAA Pascagoula Laboratory; however after each station, the footage is spot checked to ensure that the cameras recorded properly. The scientists make sure that the cameras are positioned correctly and not pointing upward in the water column or down on the ocean floor, that the field of view is not obstructed by an object like a rock, and that the water is clear enough to view the fish in sight. When we first began the Reef Fish Survey, most of the fish we saw were red snapper. As we have moved up in latitude toward the Flower Garden Banks Marine Sanctuary, the diversity of fish has increased.
There are 14 federally designated marine sanctuaries in the United States and the Flower Garden Banks is the only one located in the Gulf of Mexico. The Banks are essentially three large salt domes that were formed about 190 million years ago when much of the Gulf evaporated into a shallow sea. When the salt deposits were covered in layers of sediment, the pressure and difference in density caused the salt domes to rise and corals began to form on them about 10,000 to 15,000 years ago. (This information was obtained from the Flower Garden Banks Marine Sanctuary website. For more information, visit this informative and interesting website at http://flowergarden.noaa.gov )
Each day the camera array and CTD (conductivity, temperature, and depth) are lowered 7 or 8 times at different stations within an area about 10 X 10 nautical miles. (A nautical mile is slightly larger than a standard mile). This is handled by the deckhands and scientists who operate the cranes and position the instruments. Since we cannot participate in this task, we make sure to help out as much as possible with the fish trap, bandit reel, and taking measurements of the fish we catch.
It was exciting when we caught the marbled grouper on the bandit reel because it was so big! It weighed around 21 pounds and fell off the hook a second after the photo on the right was taken, scaring me half to death as it flopped around on the deck! I was sure it would flop itself right back into the water and there would go our impressive catch. Fortunately a deckhand was nearby to lift it back into the basket. This grouper was not on the list of fish that we needed to save for the NSIL, so after taking its measurements, it was sent to the galley and provided lunch one day for everyone on board the ship.
It has been great to see such a variety of fish on this trip. The Chief Scientist said we are pretty lucky with the fish we have caught, especially the yellowmouth grouper shown in the science log above. The tiny Reef Butterflyfish was one of my favorites with its small mouth and bright yellow tail. I’m sure the Flower Garden Banks Marine Sanctuary will continue to impress as we watch the footage from the cameras and wait in anticipation to see what the bandit reel brings up from the depths of the seafloor.
Grey Triggerfish (Balistes capriscus)
Longspine Porgy (Stenotomus caprinus)
Red Porgy (Pagrus pagrus)
Tomtate (Haemulon aurolineatum)
Reef Butterflyfish (Chaetodon sedentarius)
Marbled Grouper (Dermatolepis inermis)
Scamp Grouper (Mycteroperca phenax)
Yellowmouth Grouper (Mycteroperca interstitialis)