Distribution and status of the endangered San Joaquin kit fox, Vulpes macrotis mutica, on Fort Hunter Liggett and Camp Roberts, California

The distribution and status of the endangered San Joaquin kit fox (Vulpes macrotis mutica) was determined for Fort Hunter Liggett and Camp Roberts, California, using canid scent station transects, spotlight surveys, and live-trapping and radiotelemetry. At Fort Hunter Liggett kit foxes were distributed only in a narrow corridor along the San Antonio River from the Mission to the B-9 Tank Range. Three other areas of potentially suitable habitat were observed but no evidence of kit foxes was obtained in them. The species was widely distributed on Camp Roberts and they appeared to be common to abundant over large areas, including the Main Garrison. Characteristics of dens used by radiocollared foxes were seldom consistent with previously published descriptions because many dens were enlarged burrows of California ground squirrels (Spermophilus beecheyi). California ground squirrels were the most frequently occurring prey remains (48.2%) in scats collected at Camp Roberts; remains of insects were observed in 25.9% of the scats. Frequencies of occurrence of lagomorphs (5.9%) and kangaroo rats (Dipodomys sp.) (l.2%), preferred kit fox prey elsewhere, were unexpectedly low. The proportions of prey items in scats varied between locations. Vehicles killed 22% of the foxes found dead, 11% were killed by predators, 1more » fox became trapped in a verticle pipe and died, and a cause could not be determined for 56% of the deaths. Evidence showing that foxes bred successfully was gathered for both posts. Recommendations were made to restrict aerial applications of rodenticides to those areas outside the known distributions of the kit fox and a 1.6-km buffer, and to implement a program to monitor effects on nontarget species. 25 refs., 21 figs., 15 tabs.« less