Perceived risk, displacement and refuging in brown bears: positive impacts of ecotourism?

Ecotourism is a rapidly growing industry with unknown impacts on viewed wildlife that may require novel management action. We examined the impact of viewing activities on the behaviour of brown bears (Ursus arctos) in coastal British Columbia. Domination of the best feeding sites and human avoidance by large male bears has consistently been reported. We, however, saw displacement in time rather than space - during the viewing day large males were less active than at other times, while females cubs tended to be more active. In each year, females with cubs spent similarly high proportions of their time fishing when people were present. In years with, large male activity, less time was spent fishing when people were absent. When freed from the potential threat of large male be, females with cubs showed no measurable impact of controlled human activity. Human presence at a feeding site impacts the behaviour of brown bears, but not as expected. Temporal avoidance of hurt activity by large males was observed; indications that they departed upon satiation, before the arrival of morning tours, however suggests that there was little energetic impact. By displacing large males, viewing activities created a temporal refuge, enhancing feeding opportunities for subordinate age/sex classes. With the strong positive relationships between mean female mass and lit size, this may in turn increase population productivity. (C) 2004 Elsevier Ltd. All rights reserved.