Impact of forest diseases on small-mammal prey of the Mexican spotted owl

Studies were conducted in the Sacramento Mountains of New Mexico to examine if and how forest diseases and other small-scale disturbances influence the abundance and distribution of small mammal prey of the Mexican spotted owl. Diseases largely occurred concurrently as complexes with other disturbance agents, and these interactions were reflected in the structure of the canopy and composition of coarse woody debris and re-colonizing vegetation. The spatial distribution and abundance of five small mammal prey species were characterized and their associations with specific diseases and other disturbance agents were analyzed. Results suggest that different prey species responded differently to conditions created by various disturbance agents. Mexican woodrats, for example, avoided disturbed areas. Mexican voles, long-tailed voles, and brush mice showed a preference for size, cause and character of disturbance. Deer mice were found both within and outside disturbed areas.