Pacific NW is as far as some migrating gray whales go
Wednesday, March 30, 2005 7:18 AM PST
By Associated Press
SEATTLE (AP) -- During the great annual gray whale migrations between feeding grounds in the north Pacific and breeding spots off Mexico, about 200 individuals apparently take up "seasonal residence" in the Pacific Northwest, scientists say.
Six gray whales, for example, have been spotted around Whidbey Island nearly every spring since 1991, says biologist John Calambokidis of Olympia-based Cascadia Research. Other small groups of gray whales return annually to preferred spots along the coasts of Oregon and British Columbia.
"In recent years, we've done a much better job identifying these seasonal resident animals," Calambokidis said. In some cases, "we have evidence they don't go to Alaska. They migrate south to the breeding grounds but seem to make this their primary feeding area."
Also, he said, unusually high numbers of beached grays reported in the spring of 1999 and 2000 apparently did not mark the start of a population decline for gray whales.
"The mortality since then has been very low," he said.
Calambokidis presented recent research about grays as the Puget Sound Georgia Basin Research Conference got under way Tuesday at the downtown Washington State Convention Center. The three-day session, featuring scores of scientists on a range of topics, is sponsored by the state's Puget Sound Action Team and Environment Canada. Gov. Christine Gregoire scheduled a 15-minute address Tuesday on her "Vision for the Sound."
Historically, Calambokidis said, gray whales that ventured inland were likely more vulnerable to shore-based hunters than those that swam farther offshore, churning all the way north to the Bering and Beaufort seas of Alaska and the Chukchi Sea off Siberia.
The ones that stop in the Northwest tend to not have as many young as the larger population, he said. Determining the gender of the seasonal residents is a work in progress, but females with calves tend to start the migration late and inland stops "may not be advantageous" for them, Calambokidis said.
Some of the returnees move on in early summer and may in fact head north, he said. Some only drop in once or twice. Grays seen farther inland, in central and south Puget Sound, tend to be stragglers that forage for food and then rejoin the migration.
There was a surge in reports of dead, beached gray whales five years ago, when population estimates peaked at about 27,000 and the Makah Indian Tribe moved to reaffirm its whaling rights under an 1855 treaty.
While most whale deaths occur in the ocean, the 50 carcasses found on Washington state shores alone in 1999-2000 may have marked a converging of two extremes, Calambokidis said: The whale population reaching its maximum carrying capacity and a natural downturn in the cyclical availability of food and prey.
Many researchers believe both the high population number and the big die-off were "blips," Calambokidis said.
"That's why there was a dramatic event, instead of a gradual tapering off." Records from around the Northwest indicate that the "major mortality event" was a very isolated incident, he said.
On average, Washington state has four gray whale beachings a year, based on reports from the regional stranding network that has been in place since the 1970s, Calambokidis said.
"We haven't really changed our response to strandings," he said. A beached whale carcass as much as 40 feet long is hard to miss in a populated area, while dead whales on remote stretches of beach may go unnoticed.
Recent gray whale counts conducted along the migration route suggest the population may have settled at about 17,000 animals -- roughly the pre-whaling total, Calambokidis said.
Gray whales, the first creature listed for protection under the Endangered Species Act, were decimated by commercial whaling that peaked in the late 19th century.
Their removal from the Endangered Species List in 1994 prompted the Makah to reclaim whaling rights after 70 years. The issue has been bogged down in federal court appeals since the tribe killed a single whale in May 1999.
Antiwhaling activists characterized "resident" gray whales as a separate population that warranted special protections. Some definitions of Makah whaling grounds limited the tribe to offshore whales, while others allowed whaling some distance into the Strait of Juan de Fuca, the waterway that divides the United States and Canada before making a sharp right into Puget Sound.
"Now that we have accurate evidence of their abundance ... it would allow someone to make estimates of what level of kills could come from that group," Calambokidis said. "We have a much more solid basis of information for either side in that debate."
Copyright 2005 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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