Bear Attack Reported Near Beaver Reservoir in Boulder CountyColorado Parks and Wildlife officials are currently responding to a reported bear attack against a human in Boulder County, near Beaver Reservoir. Photo by Peregrine Photography on Unsplash a black bear sitting in the woods next to a treeWhile Colorado's black bears are not considered aggressive, they can be dangerous. Generally, black bears avoid humans; however, they can become defensive if they are startled, protecting their cubs, or feel trapped. The Colorado Parks and Wildlife Northeast Region says that one person was injured in the attack. Colorado black bears that often get too comfortable around humans can easily destroy property and become a threat to human safety.