Cook Inlet Beluga Whales
Cook Inlet belugas are the most isolated and genetically distinct of Alaska’s five beluga populations, and have been separated from the others by the geographic barrier of the Alaska Peninsula for over 10,000 years. Their previous range had been most or all of Cook Inlet, but today that range is much smaller. Moreover, these whales are unique in that they live next to one of the most populated and fastest growing regions in Alaska: Anchorage.
The Cook Inlet beluga whale population was estimated at 1,300 animals in 1979. Sadly, the most recent estimate from the 2011 aerial survey is just 284, down from the previous year’s estimate of 340. In the last 10 years of available survey data (2001-2011), the rate of decline has been 1.1% per year. So although protected under the Endangered Species Act, today the Cook Inlet beluga whale still finds itself on a downward trajectory.
While we still do not know for sure what is affecting the Cook Inlet beluga population, Defenders continues to monitor research by scientists who are looking at the impacts of human-induced and natural changes to these whale’s environment. While no individual impact has been identified as the cause for the Cook Inlet beluga’s continued decline, we continue to examine possible threats to try to determine if the real problem could be the cumulative impact of a variety of factors. The potential impacts Defenders and others are monitoring include: changes in prey availability, changes in habitat due to climate change, increased predation by killer whales, contaminants, noise associated with construction projects and oil and gas development, vessel traffic, waste management, urban runoff, and physical habitat changes that are likely to occur as Cook Inlet becomes more urbanized. Much work remains to identify the reasons for the decline of beluga whale numbers. Additionally, we still need to educate people who live in and around the Inlet and those who visit it about the importance of the beluga whale and how to live with the protections that have been put in place.
Scientific name: Delphinapterus leucas
Length: Males,15 feet; females up to 14 feet
Weight: Adult males 3,000 lbs; females 2,000 lbs.
Lifespan: 30 - 50 years