A brown bear killed after attacking a man on the Kenai Peninsula this week showed signs of blindness, possibly explaining its bizarre behavior, wildlife officials said.
The sow bear charged a man watching birds with his wife and three young children on the north bank of the Kasilof River, which passes through the town of Kasilof south of Kenai, on Sunday. The man shoved his spotting scope into the bear's mouth, keeping his family behind him, and suffered only minor injuries, according to the Alaska Department of Fish and Game.
Alaska State Troopers shot and killed the bear and learned it had earlier attacked a telephone pole and a moving pickup. Soldotna-based wildlife biologist Jeff Selinger said he decided to collect the bear's head and spine so virologists could examine them for signs of rabies.
"It was something that we wanted to make sure we ruled out," Selinger said. "This was not normal bear behavior, by any means."
State virologists in Fairbanks looked at the brain tissue samples and determined that the bear had not been rabid, said Selinger, who conducted a necropsy on the carcass and found nothing strange about the bear's internal organs.
The bear had an empty stomach, but its damaged eyes -- fully blind in its right eye, at least partially impaired in its left -- were more telling, Selinger said. It's very rare for a brown bear to prey on a human, Selinger said. But the bear's poor vision from a ruptured right cornea and a clouded left eye could have caused it to act strangely, he said.
"In general, they can act very confused, disoriented, unsure of what's going on, and all that can lead to erratic behavior," Selinger said. "We don't know for certain if that alone did it. Obviously, there were several incidents with various people down there, and that could've gotten the bear worked up and more confused."
Biologists will continue to examine the carcass for parasites or viruses. Meantime, as more bears emerge from their dens this spring, Selinger said he hopes residents will report any odd behavior they see.
"This really brings out the importance of the public. If they see wildlife acting erratically, they should contact the Department of Fish and Game," Selinger said.
Reach Casey Grove at firstname.lastname@example.org or 257-4589.