ANCHORAGE, Alaska (25 Jan 2003) -- They were just two "teenage" Steller sea lions on the prowl, searching for tasty fish in the chilly waters off Perry Island in Prince William Sound. In many ways, they were like thousands of other 17-month-old juveniles struggling to find enough to eat during their first critical winter away from Mom. Some scientists suspect these juvenile sea lions may be dying at high rates, a major cause of the species' regional crash off Alaska. But these particular animals, nicknamed Perry and Lindy, weren't going it alone. They had an audience. A team of university and state biologists followed Perry and Lindy during three months last winter with satellite tags that kept track of how long and how deep they dived and then calculated whether the animals might have been pushing themselves too hard in quest of their food. "Perry made a series of dives that were longer than its aerobic capacity," said Jennifer Burns, a UAA assistant professor of biology. "It's like wind sprints. ... Afterwards, it would have to rest for a longer period." The study, among 160 reports presented last week at the Marine Science in the Northeast Pacific conference in Anchorage, is one example of the kind of sophisticated studies now under way into what ails Alaska's sea lions. Scientists have been analyzing sea lion diets, conducting lab studies of hormone levels, sifting for clues to physiological health in hundreds of globs of poop and tracking animals with satellite tags. Across an arc of ocean from Southeast Alaska to the mid-Aleutian Chain, biologists have been cataloging what sea lions eat, where they go and how they raise their young. | | The stakes reach deep into Alaska's coastal economy and have implications for the health of the entire marine ecosystem. The sea lion decline has confounded scientists and resource managers for nearly two decades and continues to trigger expensive closures for commercial fishing and lawsuits from environmental groups. The western stock has been listed as endangered since 1997. With $80 million in federal funding, more than 200 scientific studies at 25 institutions or agencies are now under way. Key scientists presented preliminary results from scores of studies last week in daylong sessions at the conference at the Hotel Captain Cook. Other talks focused on regional oceanography and climate change, as well as the latest findings into the aftermath of the Exxon Valdez oil spill. "I think we're learning a lot," said Bob Small, chairman of the sea lion recovery team and Alaska's marine mammals coordinator. "It's encouraging that there's a lot of new information coming out, and it's making us think." The recovery team will meet next month in Seattle, Small said. Among other things, the team will discuss what sea lion recovery will look like when it happens and tackle the latest data into predation by killer whales. |
