Grizzly bears detected at ecotourism sites are less likely than predicted by chance to encounter conflict

Abstract

Whether ecotourism can lead to human–wildlife conflict is not well understood. In Nuxalk Territory, grizzly bear (Ursus arc-tos horribilis Ord, 1815) conflict occurred ∼41–58 km downstream from ecotourism. We screened for genetic matches between individuals that encountered conflict (n = 30) and 118 individuals detected upstream via hair snags (including 34 at ecotour sites). Of these 34, one encountered conflict. In analysis Scenario 1, we considered all detected and undetected bears in the region as freely mixing, and used Bayes’ theorem to account for imperfect detection of ecotour bears among conflict samples, deriving an estimate of 1.47 (rounded to 2). Accounting for this uncertainty, we used a probability approach to ask how large the unknown non-ecotour bear population would have to be to observe this frequency of conflict among ecotour bears (2/34) by chance. The resulting population level exceeded available estimates, suggesting ecotour bears are less likely to encounter conflict. In Scenario 2, we assumed that downstream bears are not necessarily from the same population as those sampled up-stream; we compared the proportions of known ecotour and non-ecotour bears among conflict samples and found no evidence of a significant difference. Collectively, these analyses suggest other human-caused drivers of conflict.