A landscape analysis of cougar distribution and abundance in Montana, USA

Recent growth in the distribution and abundance of cougars (Puma concolor) throughout western North America has created opportunities, challenges, and problems for wildlife managers and raises questions about what factors aff ect cougar populations. We present an analysis of factors thought to affect cougar distribution and abundance across the broad geographical scales on which most population management decisions are made. Our objectives were to : (1) identify and evaluate landscape parameters that can be used to predic t the capability of habitats to support cougars, and (2) evaluate factors t hat may account for the recent expansion in cougar numbers. Habitat values based on terrain ruggedness and forested cover explained 73% of the variati on in a cougar abundance index. Indices of cougar abundance also were spati ally and temporally correlated with ungulate abundance. An increase in the number and total biomass of ungulate prey species is hypothesized to accoun t for recent increases in cougars. Cougar populations in Montana are coping with land development by humans when other components of habitat and prey populations are sufficient. Our analysis provides a better understanding of what may have influenced recent growth in cougar distribution and abundanc e in Montana and, when combined with insights about stakeholder acceptance capacity, offers a basis for cougar management at broad scales. Long-term c onservation of cougars necessitates a better understanding of ecosystem fun ctions that affect prey distribution and abundance, more accurate estimates of cougar populations, and management abilities to integrate these compone nts with human values.