By Laura and Zuckerman
SALMON, Idaho (Reuters) - The U.S. Fish and Wildlife Service is investigating the killing of a grizzly bear near Yellowstone National Park in eastern Idaho, not far from where a grizzly attacked two biologists this month, state wildlife officials said on Saturday.
It is generally illegal to kill grizzlies in the 48 contiguous states, where the bears are listed as threatened under the U.S. Endangered Species Act. But the law does allow the animals to be killed if they are threatening humans.
The caretaker of a residence near the park shot the grizzly on Friday night, said Gregg Losinski, regional conservation educator with the Idaho Department of Fish and Game.
The caretaker was armed with a high-powered rifle while at the home because a grizzly had previously torn down a bird feeder on the property and eaten the seeds, Losinski said.
State wildlife biologists have collected tissue samples from the bear for DNA testing to compare with fur taken from a site nearby where a grizzly startled from sleep charged and bit two biologists on August 15.
Also on that day, a mother grizzly attacked and wounded two hikers who unexpectedly encountered the bear's cub, park officials said.
Grizzly and human conflicts happen mostly in the autumn when the bears are driven to seek food in order to bulk up before hibernation, said Losinski.
About 600 bears roam Yellowstone and its border states of Idaho, Montana and Wyoming.
(Reporting by Laura Zuckerman; Editing by Mary Wisniewski and Xavier Briand)