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Cook Inlet beluga whale with calf

Detailed Description

Left sides of an adult Cook Inlet beluga whale (white) and her calf (gray) photographed near the mouth of the Susitna River in Cook Inlet, Alaska, the large strip of water that runs from the Gulf of Alaska in the North Pacific to Anchorage. The Cook Inlet Beluga Whale Photo-ID Project surveys the waters of Cook Inlet each year to collect data on this endangered population of whales. Part of the data collected include photos like this, which can be used to identify individual whales from the unique pattern of permanent marks and scars on their dorsal surface (i.e., back and sides). This adult whale was first photographed in 2005. The photographs also document when whales are seen with a calf. Scientists from Montana State University, the Cook Inlet Beluga Whale Photo-ID Project, University of Washington, and USGS developed a new model to use these photographic data to estimate the population’s survival and reproductive rates, something that hadn’t been possible previously. Their work showed that the population has a low reproductive rate and that some individuals in the population are not surviving as long as expected. The researchers hope that this information will provide new insights into why the Cook Inlet beluga whale population continues to decline. Photo taken under MMPA/ESA Research Permit #18016. Read more at Copyright Photo taken by Cook Inlet Beluga Whale Photo-ID Project.


Copyright photo taken by Cook Inlet Beluga Whale Photo-ID Project. For online releases, website address: For online releases, website address: USGS websites ( USGS Multimedia Gallery ( and and social media