Aspects of coexistence of two sympatric skunks in a dry forest of northwest Costa Rica

Abstract

We examined some factors that might allow for the coexistence of two sympatric skunk species, southern spotted skunks (Spilogale angustifrons) and striped hog-nosed skunks (Conepatus semistriatus), in a dry forest of northwest Costa Rica (Santa Rosa Sector of Guanacaste National Park) by comparing distribution of captures and occurrence in cover-types derived from 56 camera traps monitored from June 2016-June 2017, as well as relative activity patterns derived from these and 45 other cameras in the same area monitored irregularly from 2011 to 2016. Photo rates of spotted skunks in our study area were twice those of striped skunks. At no camera were both species photographed over the course of a year, but both species were commonly recorded in the same cover types. Photo rates of spotted skunks, however, were higher than expected in Secondary Forest and lower in Riparian Forest, whereas for striped skunks the rate was higher than expected in Mangrove and Beach Forest. Both species were clearly nocturnal, and the plots suggesting that spotted skunks were more active than striped skunks before midnight, and striped skunks were more active after midnight, were not significantly different. Differ- ences we observed in the distribution of photos by cover types and camara location for the two skunk species were notable and suggest local allopatry, likely the result of interspecific avoidance. Species-specific food habits, predation, and competi- tion with other species may also be an important factor affecting these observations, and other techniques should be used to investigate these factors. Still, cameras can provide important insights into cryptic species’ ecology.