Models to distinguish effects of landscape patterns and human population pressures associated with species loss in Canadian national parks

Abstract

It is widely accepted that large protected areas are required to effectively conserve historical species composition. However, recent analyses of mammal species loss in Canadian and African national parks contradict earlier conclusions that extent of local extinctions (i.e., extirpations) is strongly inversely related to park size, suggesting that park size alone is inadequate to predict reserve designs that may sustain biodiversity. To plan protected areas that will meet conservation goals, reserve-design models that incorporate other landscape-scale factors in addition to reserve area are needed; potential factors include the types and intensity of land use and habitat change, together with land cover types, in and around parks. Additionally, human population size around parks, and visitor density in parks may affect species loss. We quantified land use, land cover, and human population in and around 24 Canadian national parks to model effects of human disturbance and changes in natural habitats on known mammal extirpations.Multiple regression models were compared using the Akaike Information Criterion (AICc). The most parsimonious model (AICc weighting wi = 0.5391) emphasized effective habitat area in and around parks and not visitor numbers nor human population size around parks. Our model suggests that parks with as little as 3140 km2 of effective habitat area inside may be large enough to conserve historical mammal species composition if they are also surrounded by at least 18 000 km2 of effective habitat within 50 km of park boundaries.