Ontario black bear genotypes and locations (2017-2019)

Characterizing patterns and drivers of dispersal is fundamental to our
understanding of animal ecology and ultimately informing species
conservation and management strategies. In this study, we used
microsatellite data from 3,941 individual black bears, Ursus
americanus, occupying 73 spatially distinct sampling areas across
a large heterogeneous landscape to characterize dispersal via gene flow
directionality. We fit spatial models to quantified gene flow to test
hypotheses regarding drivers of putative dispersal patterns. Specifically,
we tested the relative influence of food productivity gradients, bear
density, and bear harvest on dispersal. We also evaluated differences in
gene flow patterns within and between sexes to assess sex-biased
dispersal. We found evidence suggestive of positive density-dependent,
male-biased dispersal. Our data show evidence of a relationship between
dispersal and broad food productivity gradients. Specifically, male bears
displayed preferential dispersal towards mixed deciduous forests with
higher food productivity relative to less productive boreal forests. Given
the dense sampling scheme across a continuous population, occupying a
large heterogeneous landscape, these results provide key insight as to the
likely drivers of dispersal patterns in a wide-ranging mammal.