Anchorage Daily News

A well-known killer whale that stranded and died last summer outside Cordova was carrying high levels of industrial poisons in its body, offering yet more evidence that pollutants produced thousands of miles away continue to accumulate at the top of Alaska's marine food chain.

These chemicals may now be another factor pushing a genetically unique family of Prince William Sound whales, known as the AT1 group, closer to extinction, according to local whale biologists and environmentalists.

"It's more of the same bad news," said biologist Craig Matkin, of the North Gulf Oceanic Society and the region's leading killer whale researcher.

The contaminants found in the dead whale were PCBs, or polychlorinated biphenyls, and the pesticide DDT, chemicals banned or restricted in the United States for decades but still produced in some Asian and Third World countries.

Transported across the globe on air and ocean currents, the contaminants infiltrated Alaska's food chain and have been documented at elevated levels in a wide range of animals for years -- sea otters, seals, walruses, peregrine falcons, northern fur seals and bald eagles. As the chemicals move up the food chain, they concentrate and build in fatty tissues.

As a result, among 77 killer whales tested in the Gulf of Alaska between 1994 and 1999, the highest levels appeared among animals that eat only marine mammals, the type known as transients. Among 10 killer whales sampled in 1999 and 2000, several transients appear to be among the most contaminated marine mammals ever measured.

The whale that died last July in Hartney Bay -- a closely studied harbor seal predator nicknamed Eyak -- had concentrated PCPs at about 370 parts per million and DDTs at about 470 parts per million in its tissues, according to chemist Gina Ylitalo, of the National Marine Fisheries Service's contaminants lab in Seattle.

Another transient male from the Gulf of Alaska had the highest levels ever measured in Alaska waters -- about 651 parts per million PCBs and about 1,003 parts per million DDTs, according to Matkin's report. That whale, unrelated to the Sound's AT1 group, had a dorsal fin that was bent over, a sign of ailing health among killer whales.

The results were released this spring as part of an annual report by Matkin and four other authors on the status of the Sound's killer whales for the state-federal Exxon Valdez Oil Spill Trustee Council.

Similar levels found recently in killer whales in the Pacific Northwest prompted leading biologist Peter Ross and four others to write in Marine Pollution Bulletin that "killer whales in British Columbia can now be considered among the most contaminated cetaceans in the world."

By comparison, the U.S. Food and Drug Administration standard for PCBs in fish for human consumption is 2 parts per million and the limit for DDTs is 5 parts per million.

Scientists don't know how the substances effect the long-lived, slow-reproducing killer whales. Whether such elevated levels contributed directly to the death of the 5-ton, 24-foot whale isn't known, Matkin cautioned. "We will probably never know the cause of death."

But comparable contaminant loads have been linked to reproductive failures in beluga whales of the industrialized St. Lawrence River estuary, die-offs of striped dolphins in the Mediterranean Sea and European harbor seals.

"It's clearly in the range of potential health risks," Matkin said. "It's scary stuff."

Whatever the cause, the death of Eyak furthered the decline of the AT1 group, an extended family of whales that lost 11 of 22 members in the three years after the Exxon Valdez oil spill. These whales, which have never been seen associating with other transients in the region, have not produced any offspring since before the spill.

"The upshot is that they're disappearing so fast that I don't know what we can do for them," Matkin said. "We've been debating about whether to try to get them listed under the Endangered Species Act."

Another transient whale was found dead June 25 near Johnstone Point on Hinchinbrook Island west of Cordova, an area historically used by Eyak and other AT1 whales, especially a slightly older male known as Eccles. Eyak and Eccles, named for mountains overlooking Orca Inlet near Cordova, often hunted seals together and were well known to people in the Sound.

By the time Matkin and others reached the whale to perform a necropsy in early July, the whale had begun to decompose, making it impossible to identify the animal from its markings. Tests to establish the whale's genetic background and contaminant levels haven't been completed yet, Matkin said. "But I have a bad feeling that this is one of the AT1s."

That would reduce the local group of transients to 9 -- a loss of 13 whales in 12 years, a decline never before documented among killer whales in the North Pacific.

"They're going away," said Donna Willoya, research director for the Alaska Sea Otter & Stellar Sea Lion Commission who helped Matkin perform the necropsy. "It's like a family that's dying off."

That dead whale had a belly full of seal parts and, strangely, pieces of bull kelp, Matkin said. There was no obvious cause of death.

"This looked like a healthy animal," added Willoya, who also responded to the whale death last year. "This one actually had better teeth than Eyak."

The AT1 group's ongoing problems have saddened and worried local residents. The presence of the contaminants at such high levels in the whale is especially alarming, said Kate Williams, director of environmental programs for the Native Village of Eyak. "The concern is huge."

Pat Lavin, coordinator of the Prince William Sound Alliance for the National Wildlife Federation, likened these local whales to a marine "canary in the mine."

"We see the AT1 whales and their difficulties as indicative that the ecosystem is suffering," he said. "We have a pod of killer whales that's basically on the verge of extinction, and I don't think people know that. We're definitely planning to do all we can to prevent that extinction from happening and, if it's unavoidable, to learn all we can from it."

The overall situation for three separate types of killer whales in the eastern North Pacific Ocean is complex, with some pods increasing and others in decline. For instance, the Sound's famous AB pod of resident whales has declined overall from 36 to 25 between 1988 and 2000 and is still not considered recovered from the oil spill by the Trustee Council. The number of other known Gulf of Alaska resident whales increased from 81 to 110 during the same period.

Complicating the picture even more is that biologists are still debating whether certain troubled groups of whales live independently as distinct stocks -- often a legal requirement for special federal protection -- or whether they're really part of larger populations.

The issue has been raised by a petition from environmental groups to list the Southern Residents, a population of fish-eating whales that frequent Puget Sound, under the Endangered Species Act. The National Marine Fisheries Service has not responded to the petition yet, according to biologist Robyn Angliss, assistant to the director of the Marine Mammal Laboratory in Seattle.

The same question would arise if someone proposed listing the AT1 whales, Angliss said. The agency officially includes the group as part of the Eastern North Pacific Transient stock, a population of 346 animals ranging from the Bering Sea to the Pacific Northwest.

Years of genetic testing and observation by Matkin and his associates suggest that the AT1 whales have been isolated from other transients in the region for generations. They have their own habits and appearance.

"These AT1s, they have a very unique vocal repertoire," Matkin said. "They're almost like sirens, these calls they give under water."

Unlike the noisy, gregarious pods of salmon seekers, transient killer whales stalk marine mammals in small groups, guided by a social structure that's not well understood. Among these mysterious animals, the AT1 group was once remarkably predictable. Matkin's team usually identified all 22 whales in the Sound and Kenai Fjords region every season between 1984 and 1989.

But days after the Exxon Valdez grounded on Bligh Reef and dumped 11 million gallons of oil into the Sound, several AT1 whales were photographed swimming through a slick. Two whales disappeared that year, seven in 1990, two more by 1992. Matkin believes those whales are dead.

The group's inability to rebound during the past decade might stem from multiple causes -- the oil spill taking important members, rising contaminant levels in their bodies, and the regional crash of the favorite prey, the harbor seal.

"It's extremely upsetting," Matkin said. "As far as trying to do something for these animals, it just feels like the current against them is so strong."

Still, it's unclear what the government could do exactly to protect killer whales if they were given additional legal protection, Angliss said.

When Eyak died last summer, the whale was believed to be at least 32 years old -- a relatively old male. "But there are a lot of males that live a lot longer than that," Matkin said.

The whale had been eating well. In its stomach were harbor seal chunks and claws and hair, along with a tag from a seal caught and released in Port Chalmers of Montague Island and one from a seal caught at Applegate Rock in Montague Strait.

A team of volunteers from the Prince William Sound Science Center, the Native Village of Eyak and the U.S. Forest Service salvaged the whale's remains in a project to rebuild the animal's skeleton. That project is still under way, said Aaron Lang, education coordinator for the science center.

The bones were sunk in crab pots over the winter, he added. "The sea critters did their job and ate a bunch of flesh off them." The bones are still being processed.

"We're trying to figure out the best way to approach the rearticulation," Lang said. "I think there are only three or four intact orca skeletons in the world, so it's not a process that's been done very much."

In the aftermath of Eyak's death, Matkin said, he received reports that Eccles, Eyak's longtime hunting companion, was visiting former haunts in the eastern Sound.

"He was wandering around by himself all late summer," Matkin said. "It was a sad deal."

Doug O'Harra can be reached at do'harra@adn.com and 907 257-4334.