Topographic and Habitat Use by Sympatric Barbary Sheep and Mule Deer in Palo Duro Canyon, Texas

Abstract

The topographic distribution of sympatric populations of Barbary sheep and mule deer was studied in the Dry Creek branch (65 km2) of Palo Duro Canyon in the central Texas Panhandle from February 1977 through January 1979. Each of 529 Barbary sheep sightings and 337 mule deer sightings were recorded by topographic level and nonparmetric tests were used to evaluate the null hypothesis of no significant difference in distribution between Barbary sheep and mule deer in topographic level or habitat type. There was no significant difference between species in spatial usage on a monthly basis when sightings on Bluff Sites were compared with those on Level Sites. When sightings on High Sites were compared with those on Low Sites, distributional patterns were significantly different only for February and November. There were significant seasonal differences between species in distribution by habitat type during the autumn and spring, but the aggregate distribution of sightings suggested that overall usage of space was not significantly different. These findings, when considered with the results of comparative diet studies, indicate the possibility of competition for mutally preferred forage plants. Other implications are also discussed.