Effects of bear viewers and photographers on brown bears (Ursus arctos) at Hallo Bay, Katmai National Park and Preserve

Abstract

We investigated the effects of bear viewing and photography on brown bears (Ursus arctos) that used open habitats at Hallo Bay, Katmai National Park and Preserve (KNPP), Alaska. We also investigated how bear use of the area varied with season, human presence, and time of day. We found that the mean number of bears present varied significantly with season, time of day, and human presence. There were significantly more bears present before the salmon season than during the salmon season; bear numbers increased significantly during the day, and there were significantly more bears when humans were present. Humans at varying distances least affected activity budgets of sows with spring cubs, but foraging efficiency (bites per minute) of sows with spring cubs was significantly lower with humans <50 m away than with humans absent. Fishing success (chases per catch) of large males and single bears was lower when humans were present, but fishing success of sows with spring and older cubs was higher when humans were present. We conclude that humans are affecting brown bears that use Hallo Bay and therefore the Katmai NPP Bear Management Plan is being violated as well as the act establishing the National Park Service. We recommend that managers at KNPP restrict visitor use at Hallo Bay and enforce existing policy.