NOAA Teacher at Sea
Onboard Research Vessel Hugh R. Sharp
May 9-20, 2009
Mission: Sea scallop survey
Geographical Area: North Atlantic
Date: May 12, 2009
Weather Data from the Bridge
High pressure ridge building late today until wed
Temperature: 12.22˚ C
True winds: 5KTS Seas: 2-4 ft.
Science and Technology Log
As soon as our shift began today, the dredge was already on deck so we went straight to work. After several stations I noticed that the scallop and crab count was lower than yesterday. We are working in an area called Elephant Trunk. It is named this because the bathymetry of the sea floor makes it look like one. We have many stations in this Closed area, so we may see an increase in scallop numbers as the shift progresses.
Today I learned about “clappers”. Clappers are scallop shells that have no meat in them. They are sorted out from the rest and counted. I asked Vic Nordahl why they were important and he said that clappers give us an estimation of natural mortality or predation, so they need to keep count of how many are found.
Between dredges today, I spoke with Wynne Tucker. Wynne is an oceanographic tech from the University of Delaware and is in her third season on this research vessel. Wynne does a CTD cast every third station. A CTD measures conductivity, temperature, and depth. She takes samples in the water column at depths of 50-70M. Sensors on the CTD send information to a computer where the data is recorded. The CTD also records information about fluorescence, presence of particulates, and oxygen. The data gives us a visual of the water column which is then sent to NOAA (the National Oceanic and Atmospheric Administration) for analysis. When Wynne is not doing CTD casts, she is working at many different jobs Larry Brady and I processed some special samples this evening. We usually measure 5 scallops. Two of the samples had a larval or young Red Hake inside. It lives inside the scallop shell for protection from predators and is tucked on one side of it. This is not a symbiotic relationship, rather more commensalism. I continue to be amazed about the life systems in these waters!
Elise Olivieri (the teacher from New York) and I have made plans to photograph each other as we work. We work different 12 hour shifts so we do not see each other except during the shift change. And as we have both learned, there is not time for picture taking once the work begins! Unfortunately, our pictures will not be included in our journals at this time, but will be added upon our return!
My day ended with two incredible sights. First, as I carried the special samples up to the storage cage, I looked out from the portside at a totally dark scene. You could not make out sky or sea- it all blended into …black! I have never seen anything quite like that before. The second occurred on the starboard side just as I was ending my shift. Glen Rountree (NOAA Fisheries Service volunteer) told me he had seen a strange red light in the sky and after looking through his binoculars realized it was the Moon. Elise and I grabbed our cameras and went out on deck. It was beautiful! One solitary red light in the middle of black! It was a good way to end the day.
Question of the Day
What is the difference between symbiosis and commensalism?
Animals Seen Today
Spider Crab, Sea Squirts, Gulf Stream Flounders, and Bobtail Squid.