Black bear population reduction and recovery in western Interior Alaska

Abstract

ABSTRACT We documented the temporal and demographic recovery of a black bear (Ursus americanus) population following a 2‐year translocation program that substantially reduced both male and female bears. We estimated black bear population abundance prior to (2003), during (2004), and following (2007 and 2010) translocations in a 1,368‐km2 study area in western Interior Alaska, USA. We estimated population size of independent black bears using removal models during 2003 and 2004 and mark–resight techniques during 2007 and 2010. The pre‐translocation 2003 estimate of 83–109 (95% CI) independent bears was reduced by 96% to 0–13 (95% CI) independent bears by late spring 2004, when translocation efforts ceased. By 2007 the population of independent bears increased to 56–84 (95% CI), and by 2010 the population recovered to ≥ pre‐translocation levels (96–162 [95% CI]). The proportion of male and female bears in the post‐translocation population was similar during 2007 (50% F) and 2010 (59% F), indicating both sexes rapidly reoccupied the study area. We concluded that Interior Alaska black bear populations can recover in 4–6 years from substantial numerical reductions and recovery in our study area was likely facilitated by its relative small size, high‐quality habitat, and large surrounding environment consisting of a lightly harvested bear population. © 2013 The Wildlife Society.

Keywords

• Alaska
• independent bears
• mark–resight
• reduction
• removal models
• translocation