Travel specific resource selection by female Kodiak brown bears during the sockeye salmon spawning season

Abstract

Abstract Background Access to salmon resources is vital to coastal brown bear (Ursus arctos) populations. Deciphering patterns of travel allowing coastal brown bears to exploit salmon resources dispersed across the landscape is critical to understanding their behavioral ecology, maintaining landscape connectivity for the species, and developing conservation strategies. Methods We modeled travel behavior of 51 radio-collared female Kodiak brown bears (U. a. middendorffi) from 2008 to 2015 during the sockeye salmon (Oncorhynchus nerka) stream spawning season to identify landscape patterns associated with travel pathways. To accomplish this, we first identified behavioral states of marked individuals, and then developed a resource selection function (RSF) to evaluate environmental covariates that were predictors of selection during travel behavior. Results Landcover edges, elderberry-salmonberry stands, lowland tundra, elevation, terrain position, and stream length influenced selection for travel corridors. The RSF validated well and was comparable to corridors identified by pathways used by bears while travelling. Conclusions Models identified spatial predictions of the relative probability of selection while bears were travelling during the salmon spawning season and identified areas that contained potential movement corridors important for bears inhabiting Kodiak Island. Our results characterized factors influencing travel, identified important movement corridors, and provided managers with information to make informed resource management decisions.

Keywords

• Brown bear
• Foraging
• Kodiak Island
• Resource selection function
• Salmon
• Sockeye