NOAA Teacher at Sea
David Riddle
Onboard NOAA Ship Albatross IV
July 13 – 28, 2006
Mission: Sea scallop survey
Geographical Area: New England
Date: July 14, 2006
Science and Technology Log
My first shift involved getting accustomed to the job. It seems like an incredible amount of detailed instructions and procedures at first, but over time, the routine emerges. The dredge goes out and tows for 15 minutes. Then it comes back in and the inclinometer data is downloaded. The inclinometer is attached to the frame of the dredge and measures the angle of the dredge in relation to the bottom. This data allows verification that the dredge was towing at the proper angle. Then the dredge frame is moved, the net is dumped, and I take a photo of the catch with Amanda holding a sign telling which tow and which location. Then we dig through the pile, on hands and knees, sorting out scallops, clappers (recently dead scallops with the shell halves still hinged), all fish species, and every third station we save and count crabs and do a random sample count to estimate the number of starfish. Starfish are scallop predators. Also, at every third station before we do a tow the CTD measuring device is lowered over the side. CTD stands for Conductivity, Temperature, and Density, and these numbers are used to calculate salinity. The temperature data from the CTD helps establish the conditions which scallops may or may not prefer. CTD data is not only related to the Scallop Survey, but NOAA ships regularly collect data that is used by scientists working on other projects.
The location of each tow is selected randomly by computer within various strata which vary by depth. There’s a navigational chart posted on the wall that shows the precise location of all the areas being sampled. Some samples are taken from areas that are closed to commercial fishing, for resource management purposes. Some areas may be closed indefinitely while others are rotated or allow fishing on a “restricted access” program.
Sightings: In the afternoon, whales were blowing on the horizon, too far away to see any more than that. I counted five spouts together in one place, then two more a little farther behind. Hammerhead shark, reported from the bridge. I saw the fin. Dolphins alongside in the dark: they look silver-gray, in the reflection of the ship’s lights.
Personal Log
I awoke feeling fine, and went around taking some video of fishing operations. But I felt uneasy from late morning on. Twelve hours is a long time to work when feeling queasy, but interestingly, when I was focused on a specific task, even something as simple as shucking scallops and talking, I was less aware of my discomfort. I was tired toward the end of my 12-hour shift, tired of feeling queasy, tired of the half-asleep feeling that comes from the anti-nausea medication. A shower and bed were most welcome!
