During European settlement the bobcat was extirpated from the midwestern United States and many parts of the Great Lakes region. Over the past decades, bobcat (Lynx rufus) sightings have become more common in the region however, suggesting that bobcat populations are increasing and spreading northwards. Bobcat populations do not appear to be redistributing evenly throughout the Great Lakes region however, suggesting that landscape configuration could be playing an important role in impeding recolonization by the bobcat. The Great Lakes and the St. Lawrence River are imposing barriers to movement for wildlife. In addition, urban and agricultural development dominates southern Ontario, Canada, and may be impeding bobcat from colonizing this area, although some evidence suggests that indicates that the bobcat can cope with such landscapes. The main objective of this research is to evaluate the functional connectivity of the bobcat in the Great Lakes region to test whether this felid is less abundant in southern Ontario because of local habitat conditions or larger scale landscape configuration. We genotyped bobcat pelt samples collected from trappers across the Great Lakes region at 14 microsatellite loci. We then tested 3 connectivity models that we predict would explain the current expansion of the bobcat.
Results/Conclusions
We found a clear division between individuals found in the northeast and northwest n Canada. In addition, there is a higher gene flow between individuals at the northern edge of the bobcat range in Ontario and the Upper Peninsula of Michigan compared to individuals found in Quebec, New York and the Lower Peninsula of Michigan. This indicates that individuals found in southern Ontario are more likely to have descended from individuals from the Upper Peninsula of Michigan. Landscape configuration of the Great Lakes could be playing a role. However, the connectivity model that best explained the observed gene flow pattern defined every land cover element except forests as highly resistant. Our results suggest that the functional connectivity of the bobcat in southern Ontario is relatively low and is caused in part by the low amount of forest cover. Less mobile and adaptable terrestrial species are unlikely to successfully keep up with the current rate of climate change through this highly fragmented area.