Habitat and population status of desert mule deer in Mexico

Abstract

Historically, desert mule deer (Odocoileus hemionus crooki) were distributed across the Chihuahuan Desert region in Mexico. Overgrazing and illegal hunting have been responsible for the dramatic reduction in the desert mule deer population. Through the introduction of hunting fees, desert mule deer could represent an important source of income for Mexican producers. In addition it could stimulate programs favoring sustainable management of Chihuahuan Desert ecosystems. Twenty sample units were established across Chihuahuan Desert regions in Coahuila and Nuevo Leon, Mexico. The deer population in each unit was surveyed using diurnal and nocturnal transects. Pellet group counts were conducted to provide an additional index to deer density. In each sampling unit, 50 2×5 m plots were established. Vegetation cover and diversity were also determined. We used range indicators to establish vegetation condition and trend. Correlation analyses were used to evaluate relationships between the deer population and habitat variables. Desert mule deer were present in only two of the sampling units. Range condition was at risk in 18 of the 20 sampled areas and poor in the other 2. Grass cover (%) (r=0.56), ground cover (r=0.53), range deterioration index (r=−0.29) and downward trend index (r=−0.42) were the highest correlated variables with mule deer occurrence.