Utilization of tallgrass prairie by pronghorn in winter and spring based on GIS techniques.

Abstract

A portion of the Flint Hil(S of eastern Kansas is currently occupied by a herd of pronghorn (Antilocapra americana) that co-exist with cattle. This portion of Kansas was previously occupied by pronghorn that benefitted by a commensal relationship with bison (Bos bison). Disturbed areas around salt licks put out for cattle were noticed to be used by pronghorn during winter. A Geographical Information System (GIS) database was developed and used to help study the utilization of disturbed areas by pronghorn during winter and spring. Pronghorn were observed foraging at disturbed areas during winter and were generally more approachable than at other times of the year. Herds were located with the aid of radio telemetry and were plotted on topographical maps. Thirty-eight disturbed sites were located. Locations of herds and disturbed sites were entered into the GIS along with digitized information of the roads and streams within the study area. Ten bands with 200 m widths were created around disturbed sites to show proximity of pronghorn herds. Of the 158 plotted herd locations, 13.3% were within 200 m and 29.7% were within 400 m of a disturbed site. Results showed that herd site locations were greater than expected (P < 0.001) on or near disturbed sites when compared to the entire area used by pronghorn during my study. Disturbed sites were analyzed with corresponding reference sites to look for differences. Disturbed sites contained significantly less dead forb cover (P = 0.0003) and dead grass (P = 0.0001) cover, but less bare ground (P = 0.0001). Disturbed sites that were used by pronghorn contained significantly less (P < 0.05) rock, dead forb cover, and dead grass cover, and more bare ground. Salt lick areas were likely used during winter for their concentration of green vegetation and salt content.