Borough hopes sea-lion science will ease fishing curbs

Officials say declining number of Steller sea lions may be due to an undercount

Posted: Monday, July 19, 2004

SAND POINT - Marine biologist Cathy Hegwer thumped on a 5-gallon plastic bucket and did her best to look intimidating, but a braying Steller sea lion was having none of it.

The bull - 1,000 pounds or so - stared at Hegwer before letting loose with a seven- or eight-second bellow that quivered the knees like the roar of an African lion.

Hegwer needed the big fellow and about 10 companions to briefly leave their haulout on Sea Lion Rocks, one of the tiniest of the Shumagin Islands, south of the Alaska Peninsula. Hegwer and two assistants had climbed from a bobbing skiff up 10 feet of kelp-covered rock to collect scat, which would tell researchers what the Stellers had been eating.

Hegwer's scat collection, along with counts from boat and airplane, are part of a three-year, $565,000 study to learn more about Shumagin Island sea lions and how they fit into an 80 percent population decline in most of Alaska since 1975.

Steller sea lions have been listed as an endangered species since 1997 by the National Marine Fisheries Service. Hegwer is working under a federal grant obtained by the Aleutians East Borough, where the cod and pollock fisheries have been severely restricted by protection for sea lions.

Borough officials want to show that the sea lions have been undercounted in their region and have not declined because of local commercial fishing, which provides the economic lifeblood to six borough communities.

The restrictions prevent fishermen from transit within three miles of rookeries unless weather endangers their lives. Restrictions on sea lion critical habitat sometimes mean no trawling within 20 miles of rookeries. Fishermen carry vessel monitoring devices so the Coast Guard can track their location.

"It's managing our fishery now," said Beth Stewart, the borough's resource manager.

No one knows why the sea lion population crashed west of Alaska's Panhandle. Speculation falls into two categories.

"Bottom-up" hypotheses say something affected sea lion environment: Fishing or climate change reduced prey; a nonlethal disease reduced sea lion foraging efficiency; or pollutants concentrated in the food chain reduced their fertility.

A "junk food" theory holds that sea lions for some reason had to switch from eating fatty herring, sand lance and capelin to lowfat cod and pollock.

"Top-down" hypotheses look at factors that kill sea lions independent of the ability of the environment to support the population: Predators such as killer whales or sharks switched from eating other prey to sea lions; subsistence hunters killed more than they reported; or pollution or disease directly killed sea lions.

Aleutians East Borough officials contend the sea lion decline is not due to food taken away by local commercial trawlers. In all the studies to date, no one has ever found a skinny sea lion, Stewart said.

"If they're starving, I'm Twiggy, and my doctor's not buying that," she said.

Banned from sea lion hangouts, the small trawlers have been jammed into remaining fishing areas or forced to fishing grounds far from their protected waters.

Louis McGlashin, skipper of the 58-foot converted seiner Advancer, pulls out his laptop computer to show where he once made tows off Castle Rock and Bird Island. Both are now off limits.

Last winter, he and his crew fished near Adak in the Aleutian chain. On the way, near Seguam Island, he charted his course based on a weather report that said winds would blow from the southwest. Instead, three miles off shore to avoid a sea lion rookery, he got caught in strong east winds.

"It must have been blowing 80 or 90 trying to get back to shore," he said. "That was hairy."

A trip to Adak and back costs $6,000 in fuel alone. Everyone dreads it, he said, because of the 125 miles of open water. But he goes, even though his vessel is undersized for the fishery.

"It's really dangerous," he said. "It could have been our demise."

Borough officials believe Shumagin sea lions are more plentiful than reported in federal surveys. Biologists survey the Shumagins by air once a year, in June or July, Stewart said.

"We're not getting a true picture of how many critters there are," Stewart said.

The borough's grant will send Hegwer flying over the Shumagins out of Sand Point on Popof Island four times a year to document seasonal distribution of sea lions. Last month, weather allowed her to make six flights in patterns established by federal researchers.

At Sea Lion Rocks a few days later, the sea lion bull was already in a foul mood and not eager to budge for a few puny humans. Mating season makes all bulls aggressive - perhaps magnified by a two-month fast. This one had a bloodied back, neck and flipper, evidence he'd lost a territorial fight with another male and would not be satisfying his sexual drive with a harem at a rookery.

Hegwer approached to within 12 feet, but the recalcitrant bull wouldn't leave until Ruehl Holmberg, piloting the skiff that had delivered Hegwer, pounded an oar on the seat. Noise from two directions chased the beast into the water.

That allowed Hegwer and her assistants to collect the feces, a material so potent it can bring tears to a man's eyes.

Hegwer, keenly aware of fish politics, likes that her science is community-based and driven by a practical need, not something esoteric. She also wants to contribute to the general knowledge of Steller sea lions.

"It's amazing what we still don't know about them," she said. "They're notoriously difficult to study."

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For more, go to www.nmfs.noaa.gov



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