Predation risk and habitat selection in culturally significant herbivores of the boreal forest

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This proposal involves a study of how food chains are structured, by contrasting herbivore foraging and behaviour in areas of the Northern Boreal Initiative (a development frontier) in Ontario, where wolves dominate, to areas of Newfoundland, where wolves are absent and coyotes are recent arrivals.  The herbivores chosen for study, moose and beaver, are dominants in the boreal forest ecosystem and also culturally significant, for example, as hunting and trapping resources.  This study emphasizes questions of the case for top-down (predator) effects in the boreal forest, the role for natural and anthropogenic disturbances in changing predator-prey dynamics, and enduring top-down effects evident in vegetation and in soils.  A key hypothesis, for example, is that selective foraging by beavers and moose alters soil nutrient availability, indirectly limiting plant growth, and that in the absence of other disturbances and especially in the absence of predators, this indirect effect becomes limiting to the herbivores themselves via changes to soil processes.  The presence of predators regulates this effect, while moose and beavers are indirect competitors over the long term via changes to habitat.  Testing these hypotheses potentially fills a knowledge gap in resource management through comparisons among regions. This study proposes to engage four students in soil survey, vegetation survey, analysis of radio-tracking and existing GPS telemetry data, as well as in questions of fundamental discovery.  A basic premise of this proposal is that trait-mediated interactions among predators and herbivores are sufficient yet under-explored as potential top-down terrestrial ecosystem effects.  Such interactions would include changes in foraging behaviour in the presence of predators that evolve such that herbivore density is lower than it would be if predation alone were limiting populations.  This study also contrasts the relative effects of predation, trapping and forest disturbances in specific areas where persistence and population dynamics of beaver colonies will be explored.