zondag 9 november 2008

Killer whales up for risk assessment

An independent Canadian advisory panel will meet later this month to assess the status of one of the ocean’s top predators: the killer whale.

But whale experts suggest the Committee on the Status of Endangered Wildlife in Canada, known as COSEWIC, is unlikely to recommend sweeping changes to the species-at-risk designations of five distinct orca populations.

The designation of so-called "southern residents," a population of 83 whales found in Puget Sound and the southern end of the Strait of Georgia, is unlikely to change, said Lance Barrett-Lennard, an adjunct professor at the University of British Columbia and co-chair of a federally-appointed orca recovery team.

The southern residents are currently designated as "endangered," the most serious risk assessment.

"They’re in pretty rough shape. At the time of the last COSEWIC assessment, they were given an endangered listing. Their situation hasn’t really improved since then," Barrett-Lennard said.

"That population, at 83 animals, is just hanging on by the skin of its teeth. If it was any other species, we’d think that they were very likely to be goners."

Barrett-Lennard co-wrote a paper to be presented at COSEWIC’s meetings in Ottawa Nov. 25-28, where the arm’s-length scientific body will assess the status of killer whales.

His paper will shape COSEWIC’s final report to Environment Minister Jim Prentice, who can accept the recommendations, reject them or send them back to the panel for further study.

Barrett-Lennard wouldn’t divulge his paper’s findings. However, he and other whale experts say it’s doubtful COSEWIC will recommend changes to the status of southern residents.

Watchers of the southern residents have reported declining birth rates, a loss of blubber and the onset of a condition known as "peanut head," a sign of starvation possibly resulting from a shortage of salmon the orcas feed on.

Seven of the southern residents recently disappeared off the north coast of Washington and southern British Columbia and are presumed dead.

The killer whales suffered a 20 per cent decline in population between 1993 and 2003 before recovering slightly. But some worry they are perilously close to extinction. "Pretty soon you’re getting to the point where there aren’t enough to significantly add to the population, or have any potential for adding (to the population). It would eventually die out, just natural mortality," said Ken Balcomb of the Center for Whale Research in Friday Harbor, Wash.

"It’s quite critical. We have about a dozen females now, and we had just lost two, so we’re down to a dozen. If we lost two a year for the next five years, we’re basically out of reproductive whales."

Eight environmental groups have taken Ottawa to court, demanding the government invoke the federal Species at Risk Act to protect the southern residents’ habitat. The environmentalists want the federal government to make some areas off-limits to vessel traffic and close some salmon fisheries to preserve fish stocks.

COSEWIC may also recommend Ottawa upgrade another pod of about 200 orcas, found in the coastal waters of northern B.C. and southeastern Alaska, from "threatened" to the more serious "endangered" designation.

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