Sources and rates of mortality of the San Joaquin kit fox, Naval Petroleum Reserve No. 1, Kern County, California, 1980-1986. [Vulpes macrotis mutica]

摘要: Sources and rates of mortality the San Joaquin kit fox (Vulpes macrotis mutica) were studied from 1980 to 1986. Of 270 foxes radiocollared, 225 recovered dead. dead 53.8% (121) killed by predators, 10.7% (24) vehicles, 4.4% (10) died causes other than predation, 31.1% (70) unknown causes. Contingency-table analysis was used assess relationship between cause death sex, age class (juvenile adult), habitat type (undeveloped developed), year (1980-1986). More adults in undeveloped vehicles juveniles; more female juveniles developed adults; habitat; predators later years study early years. Over 90% collared as their first or second year. Fourteen based on estimated using maximum-likelihood estimation. Mortality higher for juvenile (x-bar = 0.74) adult 0.52). For asmore » juveniles, there no significant difference survival two types sexes. increased Because coyote predation a major control program implemented 1985 should be continued its effectiveness evaluated monitoring fox, coyote, prey populations.« less