Polar mission

Marylanders are on international team gathering climate change data

Still other researchers canvassed the open waters around St. Lawrence Island for flocks of spectacled eiders, large sea ducks that winter in the eastern Bering Sea. Their numbers have plummeted since the 1970s, and they're listed as threatened.

Suspected causes include hunting pressure, chemical contamination and changes in food supply. Like walruses, they dive to the bottom to feed on the mollusks and little crabs that have declined over that period.

Researchers aren't sure how many Pacific walruses there are in the Bering and Chukchi seas. A 1990 aerial survey estimated 200,000, but the tally is considered soft because the animals spend most of their time in the water, where it's hard to count them. A petition has been filed to classify them as endangered, however, because of the threats posed by changes in their icy habitat.

Their sampling done, the scientists returned to Dutch Harbor, Alaska, and flew home at the end of March, past erupting Mount Redoubt. Back in their labs, Cooper and the others now turn to analyzing, comparing and publishing findings from the data they collected in those few weeks - a process that will take months or years.

"Most of the work from this cruise is still ahead of us," Cooper said.

This year, scientists are nearing the midpoint in the six-year Bering Sea Project. Ultimately, they hope this cruise and the rest of the study will help them identify the pattern in changes they're seeing. They will use that knowledge to predict future conditions.

"It has huge implications, and it's very complicated to figure out," said Wiese, of the Pacific Research Board. "There's a lot of changes, and the changes are occurring quickly."