Human impacts on isolation and diversity of wildlife populations

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The links between habitat fragmentation (e.g. good habitat remaining in fragments), population isolation and decrease in size, loss of genetic diversity and extirpation of populations are foundational for ecological theory. However, only recently have some empirical studies emerged unequivocally indicating the lasting impacts of habitat fragmentation through effects on genetic diversity of populations in particular -the focus of my research program. Owing to decreased movement between fragments (lack of connectivity) and fewer individuals in fragments, populations could become genetically isolated -which is known to influence risk of extirpation. My research program investigates population connectivity, genetic isolation, genetic diversity and abundance of three species, with different habitat requirements, roles in the food web and conservation statuses: wolves (a habitat-generalist), wolverines (a habitat-specialist species of conservation concern) and caribou (a threatened habitat-specialist, and prey of wolves). Fragmentation would be particularly consequential in species of conservation concern or threatened, such as wolverines and caribou, where populations have reduced sizes. However, species of large terrestrial mammals are highly mobile and long-range dispersers, which provide connectivity. I will determine habitat selection for the three study species and evaluate lack of critical habitat between ranges. My focus on habitat is fundamental from a conservation biology point of view, as the conditions that I will describe could be managed to achieve environmental sustainability. Connectivity could be re-established by improving habitat between fragments. In the environment between fragments, the outcome of predation might be impacted by human features. Caribou populations in western Canada seem to experience genetic isolation, owing to (a) poor habitat between fragments and (b) wolf predation risk over the landscape between fragments (wolves are abundant and use roads to predate more efficiently). Other species (e.g. wolverines) are also sensitive to human impacts, and may also be limited by wolves if these occur at high densities. I will further investigate if wolf-caribou relationships influence genetic isolation of caribou, and if these mechanisms are broadly transferable to other interacting organisms (if the relationships are hypothesized), for example to wolves and wolverines. Overall, my research program investigates habitat alterations and their effects on genetic isolation, despite high dispersal abilities of species, and also advances science (and its application towards conservation) by uniquely evaluating responses and interactions among species, as these interactions may contribute to isolation. My research program has immediate applications for conservation of threatened terrestrial species, where populations have reduced sizes and are becoming genetically isolated, and habitat could be restored to allow for connectivity.