Description of graphic: Recent directional gene flow (ca. 3–10 generations) calculated on the basis of allelic frequencies (number of migrants, m) among polar bear clusters. Data generated using the program BAYESASS , examining gene flow relationships between the four clusters of polar bears (Southern Canada (SC; red), Canadian Archipelago (CA; blue), Eastern Polar Basin (EP; yellow) and Western Polar Basin (WP; green)), identified by program STRUCTURE analysis of microsatellite data. Arrow widths represent only directional gene flow values that are significantly different from zero (no migration) and from the value for migration in the opposite direction.
Recent scientific research indicates that circum-Arctic polar bears are relocating to the Canadian Archipelago as a result of climate changes in the Arctic.
“We provide an expansive analysis of polar bear (Ursus maritimus) circumpolar genetic variation during the last two decades of decline in their sea-ice habitat. We sought to evaluate whether their genetic diversity and structure have changed over this period of habitat decline, how their current genetic patterns compare with past patterns, and how genetic demography changed with ancient fluctuations in climate. Characterizing their circumpolar genetic structure using microsatellite data, we defined four clusters that largely correspond to current ecological and oceanographic factors: Eastern Polar Basin, Western Polar Basin, Canadian Archipelago and Southern Canada. We document evidence for recent (ca. last 1–3 generations) directional gene flow from Southern Canada and the Eastern Polar Basin towards the Canadian Archipelago, an area hypothesized to be a future refugium for polar bears as climate-induced habitat decline continues. Our data provide empirical evidence in support of this hypothesis.”
Abstract in open source scientific article, Implications of the Circumpolar Genetic Structure of Polar Bears for Their Conservation in a Rapidly Warming Arctic, (2015), as found at this location
PDF of journal article including figures: PLOS ONE_ Implications of the Circumpolar Genetic Structure of Polar Bears for Their Conservation in a Rapidly Warming Arctic
Figures in article located here at http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0112021