Pronghorn antelope studies on the Jornada del Muerto

TitlePronghorn antelope studies on the Jornada del Muerto
Publication TypeThesis
Year of Publication1980
AuthorsGhaly MYousif
Number of Pages50
Date Published1980
UniversityNew Mexico State University
CityLas Cruces, New Mexico
Thesis TypeM.S. Thesispp
Call Number00503
KeywordsAntilocapra, reproduction, Antilocapra,distribution, dissertation, dissertations, mammal, Antilocapra, mammal, pronghorn antelope, Antilocapra, pronghorn antelope, SEE <ANTILOCAPRA>, theses, thesis
AbstractPronghorn antelope (Antilocapra americana) were studied during summer and fall 1979, and winter and spring 1980 at the Jornada Del Muerto Plains, 23 miles north of Las Cruces, New Mexico, to determine the actual locations of pronghorns, their numbers, vegetations utilized and seasonal movements. Pronghorn numbers were determined by direct ground counts and aerial surveys. The maximum number of pronghorns observed in one day, without duplication, was considered the total count. A total of 42 and 68 pronghorns were counted in 1979 and 1980, respectively. Does began to have kids about the 5th of May and stopped the 18th of May in 1980. High kid production in 1979 (1.08 kids/adult female) occurred along with above-average precipitation (39.65 cm), which provided enough forage for pregnant females. The Jornada Experimental Range and the College Ranch contained a northern and southern pronghorn herd. The northern herd moved to the south in early winter and both herds wintered close to each other, mainly in Pasture 8 of the College Ranch. The pronghorn population was scattered in smaller groups during the remainder of the year. The study indicated that pronghorns restricted their distribution to the grassland vegetational complex within the study area. Currently the grassland complex comprises 29.4% of the total vegetation, but more than 75% of the pronghorn observations were recorded in grasslands. The size of the grassland complex and low annual rainfall are the main factors for the slow increase in pronghorn numbers. Poachers and predators possibly have a slight effect while fences did not seem to be a barrier restricting the movement of pronghorns within the study area.