A brown bear killed by Alaska State Troopers on the Kenai Peninsula, which reportedly had gone berserk, tested negative for rabies but was likely blinded in one eye and partially blind in the other, according to biologists with the Alaska Department of Fish and Game.
The 20-year-old sow attacked bird-watcher Toby Burke of Kenai. It was an unprovoked attack by a bear that had been involved with several, prior run-ins with people, Fish and Game biologist Jeff Selinger told Alaska Dispatch on Wednesday, including accounts of it lashing out at a telephone pole in one instance and a moving pickup truck in another.
Those incidents prompted Selinger to test the sow for rabies. But the bear was neither rabid nor starved: "It had about a half-inch of fat still on its belly," Selinger said.
She was blind, though.
Alaska Department of Fish and Game Veterinarian Kimberlee Beckmen examined the bear's skull and spine and discovered the sow was likely totally blind in her right eye and visually impaired in her left.
The cornea of the bear's right eye was ruptured as part of an old injury, Beckmen said. The cornea of the left eye was clouded, suggesting possible impairment, though to what extent is unknown. "Impaired vision could explain the bear's behavior," Beckmen said. A bear that is blind or suffering from severely impaired eyesight might behave defensively or aggressively in encounters with objects or beings it is unable to recognize. Beckmen believes, for example, it is possible the bear ran blindly into the telephone pole and swatted at it in fear.
Bears are normally consistent in their reactions to humans and environmental objects, but past events impact their behaviors.