Distribution and habitat affiliations of 4 species of skunks (Mephitidae) in Arizona and New Mexico

Background/Question/Methods Four species of skunks (striped skunks, Mephitis mephitis; hooded skunks, Mephitis macroura; American hog-nosed skunks, Conepatus leuconotus; and western spotted skunks, Spilogale gracilis), are sympatric in the southwestern United States, but ecological relationships among them are poorly known.  We examined distribution within Arizona and New Mexico from sightings, museum specimens, remote camera photos, and trapping records.  We determined coarse-grained habitat affiliations for all 4 species using distributional data and digital habitat maps.  We determined finer-grained habitat affiliations by recording habitat variables around den sites for radio-collared hooded and striped skunks, and used factor analysis and discriminant function analysis to characterize den sites by species. 

Results/Conclusions .  In general, spotted and striped skunks had the widest distributions in the 2 states, followed by hog-nosed and hooded skunks.  Coarse habitat affiliations differed among species, with hog-nosed and spotted skunks showing the greatest affiliations with forest/woodland habitats; hooded skunks showing the greatest affiliations with grassland and scrub habitats; and striped skunks showing the greatest affiliations with forest/woodland and grassland habitats.  Striped skunks were recorded much less in agricultural habitats than previously reported in the literature, but this may be due to the small amount of land devoted to agriculture in this region.  The overlap zone of all 4 species was coincident with the location of enzootic skunk rabies.  Factor analysis identified 2 factors characterized by den substrate and physiography; and vegetation and aspect.  Factor scores differed significantly between species, and discriminant function analysis correctly predicted 64% of cases.  Hooded skunks denned more often within rock crevices in cliffy areas or on slopes, whereas striped skunk dens were located more often in dirt dens on flatter areas.  Although all 4 species overlapped extensively, habitat use differed at both coarse and fine scales.