Habitat composition and configuration around Mexican spotted owl nest and roost sites in the Tularosa Mountains, New Mexico

The Mexican spotted owl (Strix occidentalis lucida) is a threatened subspecies whose recovery depends, in part, on both an understanding of its habitat requirements and the protection of its habitat. Therefore, we evaluated habitat composition and configuration around owl sites in the Tularosa Mountains, New Mexico, using a vegetation map derived from Landsat Thematic Mapper (TM) digital imagery and digital elevation models. Owls occupied sites with more mature mixed-conifer and mature pine and less pinyon-juniper than random sites. No difference existed in the amount of young forest between owl and random sites. After correcting for the area of the vegetation classes within owl territories, no difference existed in the mean patch size, edge distance, mean nearest neighbor distance, mean shape index, and habitat heterogeneity. We recommend retaining 235.8 ha of mature forest (124.2 ha mixed-conifer and 111.6 ha pine) around Mexican spotted owl sites, which is similar to the size of protected activity centers (243 ha) proposed by the U.S. Fish and Wildlife Service.