Density, distribution, and status of the kit fox in Trans-Pecos, Texas

Abstract

A survey was made in Trans-Pecos, Texas from August 1976 to August 1978 to determine the distribution and density of the kit fox (Vulpes macrotis neomexicana). Kit foxes are found in all counties west of the Pecos River. Their population numbers between 2,400 and 12,000 adults on 3.2 x 10⁶ ha of suitable habitat. Several methods for locating foxes were evaluated; night-lighting, predator calling, and grid ground-searching. None of these methods appears to be adequate in finding kit fox concentrations in the large, isolated regions of the Trans-Pecos. Between November 1977 and August 1978 a study was conducted on individual kit foxes on an area near Sanderson, Texas on the east side pf Brewster County. Eight kit foxes were trapped; 4 were tagged with radio collars. Each tagged fox lived in a different den. Kit foxes trapped during this study weighed an average of 1.75 kg. Total body length was 745mm, hindfoot length was 123 mm, and ear length from notch to tip was 75 mm. An average of 8 h was spent outside the den each day by a kit fox. Sixty percent of this time was spent foraging in the washes. At least 25% of a kit fox's day was spent hunting. Two vegetative types were used by a kit fox within its range. Desert scrubland was utilized for denning and vegetated washes were utilized for hunting. Vegetation on the denning areas was sparse and there were few small animals present. The washes were heavily vegetated and supported more small animals. Kit foxes are not in danger of extinction in Texas at this time. Their numbers should remain stable if trapping and predator control do not increase and suitable habitat does not decrease.