Beluga Whale Numbers in
Alaska's
Cook Inlet Remain Stagnant and Could Be Declining
http://abcnews.go.com/
By MARY PEMBERTON
The Associated Press
ANCHORAGE, Alaska - A survey of beluga whales in Cook Inlet finds that numbers remain stagnant and could be declining despite a lengthy effort to get the white whales to rebound.
Fisheries biologists with the National Oceanic & Atmospheric Administration conducted an aerial survey of the inlet just southwest of Anchorage early last summer to count the belugas. An analysis of the survey data indicates there were an estimated 278 beluga whales in Cook Inlet in 2005, down from 366 the year before, scientists said Friday.
The estimate, while lower than previous years, does not necessarily mean numbers are falling, said Rod Hobbs, a researcher at the Alaska Fisheries Science Center in Seattle, who conducted the population analysis. However, the best that can be said is numbers are remaining flat, he said.
"We expect a certain amount of variability from year to year and survey to survey, however this falls near the lower limit of the expected variability for a stable population," Hobbs said.
There were an estimated 1,300 belugas in Cook Inlet in the 1970s. The goal is to help the whales recover to about 780 animals.
The reason for the stagnant numbers remains largely a mystery, Hobbs said.
It was believed that over-harvesting by Alaska Natives was largely to blame for the stock declining by nearly 50 percent between 1994 and 1999. But the stagnant numbers since the subsistence harvest was severely restricted has scientists looking for other reasons for why the population is not growing.
In the last seven years, only five Cook Inlet belugas have been taken for subsistence compared to an average harvest of about 70 before restrictions were enacted in 1999.
"We felt the harvest was the key problem, when the harvest was reduced the population would recover," Hobbs said. "It hasn't shown the sort of recovery we were anticipating."
So far, nothing has panned out for certain; the subsistence harvest is minimal, contaminant loads are comparable or less than other Alaska and Canada belugas and the number of strandings was within the expected range in 2004 and 2005, said Doug DeMaster, administrator of the Seattle center.
Hobbs said calving rates and available habitat are being looked at, as well as predation by killer whales, the idea being that "the harvest was fairly significant and that certainly had some impact, but may have been masking other problems that were impacting the whales."
"Nothing really stands out as a factor," Hobbs said.
The belugas were declared depleted under the Marine Mammal Protection Act in 2000. At that time, they were not recommended for listing under the federal Endangered Species Act because the subsistence harvest was believed to have been the reason for the decline.
Brad Smith, a biologist with the National Marine Fisheries Service in Anchorage, said a new review for ESA listing is being conducted and should be completed at the very latest by this fall. The new review is looking at the stagnant or declining numbers, he said.
There are five beluga stocks recognized in U.S. waters: Cook Inlet, Bristol Bay, eastern Bering Sea, eastern Chukchi Sea and Beaufort Sea. Researchers estimate there are about 60,000 belugas in Alaska waters outside of Cook Inlet.
On the Net:
http://www.fakr.noaa.gov/protectedresources/whales/beluga.htm.
http://www.fakr.noaa.gov
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