Spatial and Temporal Variability Influences on Ecology and Conservation

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One of the consequences of climate change has been increasing frequency of extreme weather events. In addition, humans continue to fragment and alter landscapes with roads, energy corridors, agriculture, urbanization, and industrial development. When taken together these changes in temporal and spatial variability have complex ramifications for ecology including several consequences for conservation, e.g., spatially structured predator-prey interactions, dampening risk by bet hedging, among-individual variation in diet (the “Tangled Bank” after last paragraph in Darwin's On the Origin of Species), and seasonal variation in harvest and predation interacting with density dependence to shape optimum harvests (the “Hydra effect”). I propose 3 field studies that develop these applications of the interface between temporal fluctuations and spatial ecology on (1) individual and spatial variation in foraging that dampens among-year variation in fitness for black (Ursus americanus) and grizzly bears (U. arctos), (2) personalities among elk (Cervus elaphus) to shape how harvests should be managed, and (3) predation and hunter harvest influence density-dependent response by bighorn sheep (Ovis canadensis). Our proposed grizzly bear and black bear studies apply habitat selection based on radiotelemetry and more recently based on DNA from hair samples collected at rub trees. We are proposing to use habitat selection methods to refine mark-recapture estimation of bear populations in spatial context. The structure of bear populations in SW Alberta suggests a source-sink balance with sinks driven by conflicts with agriculture, but complicated by temporal and spatial variation in availability of foods. Our long-term elk studies are grounded in one of the largest radiotelemetry studies ever conducted on this species with over 1 million GPS relocations accumulated during the past 8 years on seasonal ranges in SW Alberta. We have integrated models of movement with habitat selection obtaining integrated step-selection analysis (iSSA) that allows us to analyze patterns of movement by elk in context of habitats. Alberta Ministry of Environment and Parks plans to implement an experimental change in elk harvest regulations in our study area where we will document demographic and behavioural responses by elk. Finally, we are initiating a new experimental study of cougar (Puma concolor) predation and hunter harvest of bighorn sheep. We have extensive radiotelemetry data on cougars already and Alberta Environment and Parks will implement extended cougar seasons on randomly selected Wildlife Management Units designed to reduce predation on hunted populations of bighorns. Tools of telemetry, mark-recapture, and our new iSSAs allow us to marry spatial ecology with population biology in novel ways with direct applications for conservation biology and wildlife management.