Wildlife researchers have completed a study that may settle the question of why, in October 2009, a group of coyotes launched an unprovoked fatal attack on a young woman who was hiking in a Canadian park. Researchers concluded that the coyotes were forced to rely on moose instead of smaller mammals for the bulk of their diet — and as a result of adapting to that unusually large food source, perceived a lone hiker as potential prey.Wildlife researchers have completed a study that may settle the question of why, in October 2009, a group of coyotes launched an unprovoked fatal attack on a young woman who was hiking in a Canadian park. Researchers concluded that the coyotes were forced to rely on moose instead of smaller mammals for the bulk of their diet — and as a result of adapting to that unusually large food source, perceived a lone hiker as potential prey.