Simulation of conservation and management of woodland caribou

Abstract

The decline in woodland caribou ( Rangifer tarandus caribou) populations in Alberta lead to classification as a threatened species. Rapid industrial development continues to affect caribou habitat. Natural and anthropogenic factors, which affect population dynamics, act cumulatively. We developed an interactive cumulative effects model, which could be used to assess both natural and anthropogenic factors influencing survival of caribou. This model is based on functional and numerical responses of carnivores (wolves ( Canis lupus)), herbivores (caribou and moose ( Alces alces)) and resources (lichen and vascular plants). It includes stochasticity in some elements and is aspatial (but divides habitat into categories depending on habitat type and age). Based on simulation experiments, we suggest that the most detrimental factor on caribou population dynamics is the functional loss of habitat due to avoidance of good quality habitat in proximity of industrial infrastructures. We argue that in the natural boreal ecosystem, habitat was not limiting caribou in northern Alberta, and caribou could coexist with uncontrolled wolf populations that kept caribou at low densities of about 0.1 km −2. We argue that wolf control is not a practical solution in caribou conservation and propose different alternatives. We also suggest potential thresholds for industrial development for specific interactions of different predation pressures and habitat carrying capacity.