FLEX match

Photographic identification match of a Western Gray Whale to Cascadia’s catalog of eastern North Pacific gray whales

Contact: John Calambokidis, Cascadia Research,  calambokidis(at)cascadiaresearch.org, Phone 360-943-7325 ext 104

A photographic identification match was recently discovered by Cascadia biologists comparing identification photographs of the satellite tagged Western Gray Whale (named Flex) to Cascadia’s catalog of identified gray whales from the eastern North Pacific. Western Gray Whales are considered one of the most endangered whale populations in the world numbering just over 100. Additional information on Western Gray Whales and results of this match and some of the background information on this animal including the satellite tag results are available at:




This whale, a 14-year old male nicknamed “Flex” by researchers, was first photo-identified on the Sakhalin feeding ground as a calf in 1997 and has subsequently been observed in multiple years off Sakhalin during the summer feeding season. As part of a broader effort to understand this whale’s movements, photo-identification images of him collected by the Russia-U.S. joint research program on western gray whales were sent to Cascadia Research Collective (CRC) for comparison to a catalog of over 1000 eastern gray whales identified by CRC and its collaborators working in U.S. and Canadian waters from California to Alaska. This catalog focuses on several hundred gray whales (termed the “Pacific Coast Feeding Group”) that feed during summer and fall in coastal waters between northern California and the Gulf of Alaska but also includes a small number of gray whales identified in the spring during their northward migration to the Bering and Chukchi Seas.

The photo comparison of Flex resulted in a confirmed match between Sakhalin Island and Vancouver Island. He was sighted April 2008 in the Barkley Sound area off the west side of Vancouver Island (photos by W. Szaniszlo) and then during the summer of 2008 off Sakhalin Island. This photographic match, in combination with the telemetry data, provides the first evidence that links the Sakhalin feeding ground of western gray whales to locations in the eastern North Pacific.

This whale was satellite tagged on 4 October 2010 by a team of scientists from Russia and the United States off the east coast of Sakhalin Island, Russia to document it’s movement to an anticipated unknown breeding area in the western North Pacific (see links above for detailed information). The information from satellite tags and photographic identification is providing new information on the movements and migrations of this population to the eastern North Pacific. Genetic and other data still suggests that some of the Western Gray Whales are also migrating to an unknown breeding area in the western North Pacific.