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Burrows of the endangered giant kangaroo rat, Dipodomys ingens, were found on the U.S. Department of Energy's Naval Petroleum Reserves in Kern County, California. The majority of burrows (63%) were found in areas of low relief (4.3 0.5 o , n=32) on valley floors but 28% were unexpectedly found on low relief areas (6.4 0.8 o , n=39) in the uplands. Burrows were not distributed in proportion to the areal extend of the soil series, but were concentrated in deep alluvial sandy loams. Well pads were the most frequently observed (73% of 211) human disturbance in the vicinity of burrows, but they were the most distant (150 ± 61 m, n=150). Dirt roads were observed closer to burrows (50 10 m, n=28) but less frequently (4%). Only 8 burrows were found in the vicinity of proposed petroleum developments but no projects had to me modified to avoid negatively affecting the species.RESUMEN.-Madrigueras de las ratas canguro, Dipodomys ingens, a riesgo de extinsioń, fueron localizadas en el Departmento de Energía, Reservas Navales de Petroleo en el Condado de Kern, California. La mayoria de las madrigueras (63%) se encuentran en arias de bajo relieve (4.3 ± 0.5º, n=32) en valles, pero el 28% fueron inesperadamente localizadas en arias de bajo relieve (6.4 ± 0.8º, n=39) en terrenos elevados. Las madriguera no se distribuyen en proporcion de acuerdo a la variedad de terrenos, sino concentradas en las lomas aluviales arenosas. Los disturbios humanos observados con más frecuencia (73% of 211) en la vecindad de las madrigueras son los almohadillas de pozos petroleros pero se encontran a mayor distancia (150 ± 61m, n=150). Caminos de tierra fueron encontrados cerca de las madrigueras (50 ± 10m, n=28) pero con menos frecuenciz (4%). Unicamente ocho madrigueras fueron localizadas en la vecindad de los propuestos desarroyos petroleros pero ningún proyecto se debe modificar para evitar efectos negativos que pueden afectar a la especie.3

assisted in sample preparation, data preparation, and the framing of hypotheses. Tom O'Farrell provided advice and encouragement. vii ABS'TRACT The purpose of this study was to determine whether analysis of the elemental content of , fur from San Joaquin kit foxes (Vulpes macrotis mutica) and of water and soil from kit fox habitats could be used to make inferences concerning the cause of an observed decline in the kit fox population on Naval Petroleum Reserve No. 1 (NPR-1). Fur samples that had been collected previously from NPR-1, another oil field (NPR-2), and two sites with no oil development (Camp Roberts and Elkhorn Plain) were subjected to neutron activation analysis. In addition, soil samples were collected from the home ranges of individual foxes on NPR-1 and Camp Roberts and from undisturbed portions of major soil types on NPR-1 and subjected to neutron activation analysis. Finally, wastewater samples were collected from tanks and sumps on NPR-1 and analyzed. Statistical analyses revealed that most of the variance in elemental content of fur was attributable to differences among sites. Most elemental concentrations in fur were highest at Camp Roberts and lowest on the undeveloped portions of NPR-1. Fur concentrations were intermediate on the developed oil fields but were correlated with percent disturbance and with number of wells on NPR-1 and NPR-2. The fact that most elements covaried across the range of sites suggests that some pervasive source such as soil was responsible. However, fur ., concentrations were not correlated with soil concentrations. This suggests that differences in bioavailability or in soil intake were responsible for the variance in that set of elements. Some elements that are associated with oil development do not fit this pattern. Arsenic, which was used as a biocide, is found at higher concentrations on NPR-1 and NPR-2 than other sites and, in three fur samples from those sites, at concentrations equal to hair concentrations associated with toxic effects in humans. However, the highest concentration is from a fox that lived on the periphery of NPR-1 outside the developed areas. Barium, which is a major component of drilling fluids, was also higher in fur samples from the oil fields than from other sites and was significantly correlated with the number of wells in the foxes' home range. However, the differences among sites were small and, except for comparisons of undeveloped NPR-1 with other sites, were not statistically significant. Vanadium, which is associated with petroleum, occurred at higher average concentrations in fur from oil fields than any site except Elkhorn Plain, ali of the top ten concentrations were from NPR-1, and concentrations were correlated with the number of wells. Although the differences among sites in vanadium concentrations were relatively small, the range across individuals was relatively large, which is consistent with exposure of a few air ix jlkl, , holds. However, the relationships between exposure levels and fur concentrations are stronger for no...

The effects of military-authorized activities on San Joaquin kit fox (Vulpes velox macrotis) were investigated at Camp Roberts Army National Guard Training Site from 1988 to 1991. Military-authorized activities included military training exercises, facilities maintenance, new construction, controlled burning, livestock grazing, and public-access hunting. Positive effects of the military included habitat preservation, preactivity surveys, and natural resources management practices designed to conserve kit foxes and their habitat. Perceived negative effects such as entrapment in dens, shootings during military exercises, and accidental poisoning were not observed. Foxes were observed in areas being used simultaneously by military units. Authorized activities were known to have caused the deaths of three of 52 radiocollared foxes recovered dead: one became entangled in concertina wire, one was believed shot by a hunter, and one was struck by a vehicle. Entanglement in communication wire may have contributed to the death of another radiocollared fox that was killed by a predator. Approximately 10% of kit fox dens encountered showed evidence of vehicle traffic, but denning sites did not appear to be a limiting factor for kit foxes.