Cook Inlet Beluga Whale Count Steady in 2004

NOAA Fisheries biologists have completed this year's aerial survey of Cook Inlet beluga whales. Their index count of 187 whales, the median of many counts of whale groups, is in the same range as the last seven years.

"This year's initial count points toward a stable population again," said Dr. James Balsiger, Administrator for NOAA Fisheries in Alaska. "We are hoping to see a rising trend in the next few years. There appear to be more juveniles in the population which could indicate that the population is poised to begin growing as they mature."

NOAA scientists counted each group of belugas in Cook Inlet eight or more times each day that a group was found during their annual aerial survey. The resulting index count of 187 is similar to the 174 counted in 2003 and 192 in 2002. All of these counts fall in the range that shows a stable population for the region. Beluga abundance appears to be holding steady since hunting restrictions were enacted in 1999 between NOAA Fisheries and Alaska Native beluga hunters.

The systematic annual surveys were flown June 2 through June 9 of this year. Three of the observers were from the Alaska Fisheries Science Center based in Seattle: Dave Rugh, project leader; Kim Shelden, marine biologist; and Christy Sims, contractor biologist. Two observers, Barbara Mahoney and Brad Smith, alternated from the NOAA Fisheries' Protected Resources office in Anchorage. These scientists did five surveys of Upper Cook Inlet north of Kenai. Two days were spent surveying waters around Lower Cook Inlet.

Consistent with sighting distributions observed over the past decade, all of the belugas were concentrated in a few groups over shallow waters near river mouths, especially the Susitna Rivers, in Knik Arm or around Chickaloon Bay. Although more than half of the sightings had been in Knik Arm during the past three years, none were found there this year. Instead, the largest groups were found either at the mouth of the Little Susitna River or in Chickaloon Bay. Belugas appeared to be traveling between these two areas during the period of the survey.

Belugas tend to stay a chalky-gray as juveniles, not reaching the full whiteness of a mature adult until 5 to 7 years old. Below the ocean surface, gray beluga whales are harder to see because their color blends with the silty waters of Cook Inlet.

Through painstaking video analysis more gray belugas are factored into the count after the initial raw numbers have been recorded. Paired video cameras, using both wide angle and zoom lens, are able to record beluga images that scientists can later study for precise counts. These counts can be corrected for approximations of underwater time when neither observers nor cameras can detect whales. This combined effort provides a more accurate population estimate. NOAA Fisheries began using video cameras on this project in 1994 when they discovered that video counts could be done more precisely than could be accomplished by observers in an aircraft, especially when looking at large, dense groups of beluga whales.

Alaska Natives have a co-management agreement with NOAA Fisheries to limit the harvest to no more than six beluga whales in Cook Inlet between 2001 and 2004. Hunters took only three whales between 2001 and 2003 with one whale taken per year. In 2004 all hunting of belugas in Cook Inlet ceased because of an unusually high natural mortality of 20 whales in 2003. This exceeded the 'natural mortality' limit of 18 belugas agreed on by NOAA Fisheries and Alaska Native beluga hunters.

According to Mahoney four beluga whales have been found dead this year.

The Cook Inlet beluga population is one of five beluga stocks recognized within U.S. waters.

NOAA's National Marine Fisheries Service (NOAA Fisheries) is dedicated to protecting and preserving our nation's living marine resources through scientific research, management, enforcement, and the conservation of marine mammals and other protected marine species and their habitat. To learn more about NOAA Fisheries in Alaska, please visit our website at www.fakr.noaa.gov.