We were within sight of St Matthew Island yesterday. Tony Fishbach, USGS biologist with the Alaska Science Center, wanted one more shot at tagging a walrus in the polynya south of St Matthew. He had a tag that he wanted to place in the southern end of the Bering Sea EcosystemAn ecological community together with its environment, functioning as a unit. study area. Lee Cooper, chief scientist with the science expedition, agreed to give him time to look for walrus in helicopter. It would give Dr. Cooper time to experiment with his underwater camera system that was having problems earlier in the cruise. It had warmed up to 10F with only 25 mph winds. One of the lasers on the system refused to work when it was below zero with 45 mph winds. The underwater camera is designed to record video of the sea floor as one component of the epibenthic sampling. The camera is a stand-alone system with a video camera on the surface connected to the lens, lights, and lasers. The lens, lights, and lasers are enclosed in a metal cage connected to an electronic cable that allows for independent deployment and control for benthic imaging measurements. The lasers are fine green lines that are 10 cm apart and the light is bright enough to see the bottom up to 100 m deep.
The underwater camera worked admirably in the conditions. The images of the bottom were astonishing. The sediments, mainly sand with fine gravel, were considerably different compared to the St Lawrence Island sediments, which were mainly mud. The benthic flora and fauna were different as well. Near St Lawrence, the benthic organisms lived in the sediment or infauna, compared to St Matthew Island, the benthic organisms are on the sediments or epifauna. The camera is a good tool for counting the number of organisms (species richness) and how many there are in a given area (species abundance). Dr. Cooper will utilize that data in calculating a rough estimate of available biomass in a given amount of area, which will provide some answers to questions such as ‘How much food is available for walrus at this location?' Not sure about the walrus, but I was ready to dive in myself when I saw all of the crab on the Bering Sea floor!
The walrus team came back after locating only a few walrus and were unable to tag any ofthem. However, most everyone on the Healy saw a bowhead whale, brief but spectacular, during our time on station.
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