Just how fat are the fat bears?

Katmai National Park and Preserve’s famous bears from Fat Bear Week are helping provide some answers.

  • A National Park Service survey team from Anchorage, Alaska, measures the volume of bears bulking up on the salmon buffet of the Brooks River, Katmai National Park, Alaska.

  • A lidar scan of bear 747’s volume next to a photograph of where he was standing near Brooks Falls at the time of the scan.

    Courtesy of Joel Cusick
  • A lidar scan from a different perspective of bear 747's volume. The lidar can't scan through water, so researchers must wait for an opportune viewpoint.

    Courtesy of Joel Cusick
  • Bear 435, pictured in 2019. Fat Bear Week began in 2015 as a National Park Service effort to educate the public about the bears.

  • Bear 151, pictured in 2019. A lidar scanning device only needs from 3 to 11 seconds to pass over the bears. Often, researchers measure them as they’re standing relatively still while waiting for salmon to swim upstream.

  • Bear 775, “Lefty,” photographed in September 2019.