Reintroducing San Joaquin kit fox (Vulpes macrotis mutica) to vacant or restored lands: identifying optimal source populations and candidate foxes

Endangered San Joaquin kit foxes (Vulpes macrotis mutica) currently persist as a meta- population in central California consisting of 3 core and several satellite populations. Many of these populations are small and the meta-population is highly fragmented, which increases extinction risk. Translocation is a potential strategy for increasing the number of populations. Various factors would need to be considered when selecting source populations and candidate foxes for translocation. One such factor is behavioral attributes of individual foxes, as reflected by level of boldness, particularly in response to novel resources and potential threats. We compared behavioral attributes between and within populations of kit foxes in urban and non-urban habitats, and also examined the relationship of these attributes to survival and fitness. The overall goal of this project was to identify optimal source populations and individual foxes for relocation efforts, and in particular to determine whether urban foxes could be used in such efforts

Ecology of the desert kit fox (Vulpes macrotis arsipus) in Chuckwalla Valley, California

The desert kit fox (Vulpes macrotis arsipus) is an uncommon to rare inhabitant of the Mojave and Colorado deserts in California. This previously low-key subspecies is now being threatened by a suite of direct and indirect impacts due to the rapid increase in large-scale industrial renewable energy development in important habitat areas. This study attempts to assess habitat selection by desert kit foxes in Chuckwalla Valley, CA, in the context of the increasing presence of solar energy project sites in the area. An Unmanned Aerial System (UAS) was used to assess desert kit fox burrow and vegetation density from aerial imagery, and line-transect surveys were conducted to assess desert kit fox scat, prey, and predator densities. The presence of localized land development and an existing Habitat Suitability Index were assessed using GIS. The relationship between these variables and the desert kit foxes was assessed by fitting Generalized Linear Models. I found that ecological predictors of desert kit fox habitat occupancy gauged by burrow density can contradict those of habitat use gauged by scat density. Thus, habitat suitability and habitat connectivity may be impacted differently by land development. Proximity to development directly influenced habitat occupancy and use models as well. The Habitat Suitability Index based on widely accepted desert kit fox ecology was strongly contradicted by regression results and individual observations. In addition, coyote presence was found to negatively impact habitat occupancy and use, which suggests that water availability associated with land development may indirectly impact desert kit foxes. I conclude that current knowledge and the assumptions of cumulative impacts of land development are inadequate for the assessment of the impacts of large-scale renewable energy development in desert kit fox habitat

Spartan Daily February 16, 2012

Volume 138, Issue 11https://scholarworks.sjsu.edu/spartandaily/1010/thumbnail.jp

Ice Age Elephants of the Channel Islands

Of the small company of land mammals native to the Channel Islands of Southern California none reaches large size, and, if we exclude aboriginal man and his dog, the largest is the fox. This interesting creature, once more numerous than it now is, exists under a variety of conditions on the several islands and may be seen occasionally searching for food along the seashore or living in cactus patches, brushy ravines, and on the open slopes of hills to an elevation of more than 2,000 feet. It seems to lead at present a solitary life. The island species was long ago recognized by biologists as a distinctive type, related to the mainland gray fox rather than to the kit fox and red fox. Six races have now been identified, one for each of the principal islands comprising the Channel Island group

Foxes and food subsidies: anthropogenic food use by red and Arctic foxes, and effects on Arctic fox survival, on the Arctic Coastal Plain of Alaska

Thesis (M.S.) University of Alaska Fairbanks, 2013Food subsidies have the potential to impact wildlife on the Arctic Coastal Plain of Alaska. Red foxes (Vulpes vulpes (L., 1758)) expanded their range into Arctic regions during the 20th century, and the availability of anthropogenic foods may have contributed to their success and persistence in the Arctic. Arctic foxes (Vulpes lagopus (L., 1758)) are also known to forage on anthropogenic foods in Prudhoe Bay and to forage on marine mammals on the sea ice, but it is unknown whether these strategies benefit survival of Arctic foxes. This thesis examined: 1) the importance of anthropogenic foods to the diets of red and Arctic foxes in Prudhoe Bay, and 2) the factors with the greatest effect on Arctic fox survival, including access to food subsidies in Prudhoe Bay and on the sea ice. For the first study, stable isotopes of red and Arctic fox tissues were used to infer late summer, late winter, and lifetime (for red fox only) diets. The contribution of anthropogenic foods to the diets of both species was low in late summer (~10%) but high in late winter (49%, 95% credible interval = 38-57%, of red fox diets and 37%, 95% credible interval = 29-44%, of Arctic fox diets). Estimates of lifetime diet in red foxes revealed high levels of anthropogenic food use, similar to the winter diet. To characterize the extent of competition for food resources, dietary niche overlap was examined between both species by comparing isotopic niche space. Both fox species had little isotopic niche overlap but may have greater overlap between their ecological dietary niches. Availability and consumption of anthropogenic foods by red foxes, particularly in winter, may partially explain their year-round presence in Prudhoe Bay. For the second study, nest survival models and satellite collar data were used to evaluate whether multiple factors affected survival of adult and juvenile foxes. Site and sea ice use had two times more support than the other factors. Three groups of foxes were identified based on capture location and sea ice use, which corresponded to different survival rates: Prudhoe Bay foxes, NPR-A foxes that used sea ice during more than eight 2-week periods during the winter (seven 2-week periods for juveniles), and NPR-A foxes that did not use sea ice. Both adult and juvenile foxes at Prudhoe Bay had modestly higher annual survival rates, 0.50 (90% CI 0.31-0.69) and 0.04 (90% CI 0.0-0.08) respectively, than foxes at NPR-A that did not use sea ice, 0.40 (90% CI 0.18-0.62) and 0.01 (90% CI 0.0-0.04) respectively. NPR-A foxes that used sea ice extensively had the highest survival rates. Food subsidies may have far-reaching effects on red and arctic foxes on the Arctic Coastal Plain of Alaska

Screening red foxes (Vulpes vulpes) for possible viral causes of encephalitis

Background: Next to various known infectious and non-infectious causes, the aetiology of non-suppurative encephalitis in red foxes (Vulpes vulpes) often remains unclear. Known causes in foxes imply rabies, canine distemper, toxoplasmosis, Aujeszky’s disease, as well as parvovirus, adenovirus, circovirus and flavivirus infections. In this study, particular attention was paid on bornaviruses, since red foxes are predators of bicoloured white-toothed shrews, a reservoir of Borna disease virus 1 (BoDV-1). In addition, foxes are known to be highly susceptible for viruses of the order Mononegavirales. Methods: Analyses for the presence of anti-BoDV-1 antibodies, BoDV-1-RNA and antigen were performed on 225 blood and 59 brain samples, from a total of 232 red foxes. Foxes originated from BoDV-1 endemic and non-endemic German areas. Additional investigations for the presence of rabies, canine distemper, toxoplasmosis, Aujeszky’s disease, parvovirus, adenovirus and flavivirus infections were carried out on 16 red foxes with non-suppurative (meningo-) encephalitis. A metagenomic analysis was used on three representative brain samples displaying encephalitis. Results: Among 225 foxes, 37 displayed anti-BoDV-1 antibodies with titres ranging between 1:40 and 1:2560, regardless of geographic origin. In 6 out of 16 foxes with encephalitis, canine distemper virus was detected. No evidence of any of the other investigated agents was found in the 16 fox brains with encephalitis. Metagenomics revealed no infectious agents, except for one already known canine distemper case. Conclusion: Red foxes can exhibit BoDV-1 specific antibodies without association with geographic origin or encephalitis due to bornavirus infection. The encephalitis pattern was highly conspicuous for a viral infection, but remained unclear in 10 out of 16 foxes. Thus, presently unknown infectious and non-infectious causes need to be considered and further investigated, especially since foxes also tend to occur in human proximity

Heterogeneities in leishmania infantum infection : using skin parasite burdens to identify highly infectious dogs

Background: The relationships between heterogeneities in host infection and infectiousness (transmission to arthropod vectors) can provide important insights for disease management. Here, we quantify heterogeneities in Leishmania infantum parasite numbers in reservoir and non-reservoir host populations, and relate this to their infectiousness during natural infection. Tissue parasite number was evaluated as a potential surrogate marker of host transmission potential. Methods: Parasite numbers were measured by qPCR in bone marrow and ear skin biopsies of 82 dogs and 34 crab-eating foxes collected during a longitudinal study in Amazon Brazil, for which previous data was available on infectiousness (by xenodiagnosis) and severity of infection. Results: Parasite numbers were highly aggregated both between samples and between individuals. In dogs, total parasite abundance and relative numbers in ear skin compared to bone marrow increased with the duration and severity of infection. Infectiousness to the sandfly vector was associated with high parasite numbers; parasite number in skin was the best predictor of being infectious. Crab-eating foxes, which typically present asymptomatic infection and are non-infectious, had parasite numbers comparable to those of non-infectious dogs. Conclusions: Skin parasite number provides an indirect marker of infectiousness, and could allow targeted control particularly of highly infectious dogs

Interactions between landscape changes and host communities can regulate echinococcus multilocularis transmission

An area close to the Qinghai-Tibet plateau region and subject to intensive deforestation contains a large focus of human alveolar echinococcosis while sporadic human cases occur in the Doubs region of eastern France. The current review analyses and compares epidemiological and ecological results obtained in both regions. Analysis of rodent species assemblages within quantified rural landscapes in central China and eastern France shows a significant association between host species for the pathogenic helminth Echinococcus multilocularis, with prevalences of human alveolar echinococcosis and with land area under shrubland or grassland. This suggests that at the regional scale landscape can affect human disease distribution through interaction with small mammal communities and their population dynamics. Lidicker's ROMPA hypothesis helps to explain this association and provides a novel explanation of how landscape changes may result in increased risk of a rodent-borne zoonotic disease

64-bit architechtures and compute clusters for high performance simulations

Simulation of large complex systems remains one of the most demanding of high performance computer systems both in terms of raw compute performance and efficient memory management. Recent availability of 64-bit architectures has opened up the possibilities of commodity computers accessing more than the 4 Gigabyte memory limit previously enforced by 32-bit addressing. We report on some performance measurements we have made on two 64-bit architectures and their consequences for some high performance simulations. We discuss performance of our codes for simulations of artificial life models; computational physics models of point particles on lattices; and with interacting clusters of particles. We have summarised pertinent features of these codes into benchmark kernels which we discuss in the context of wellknown benchmark kernels of the 32-bit era. We report on how these these findings were useful in the context of designing 64-bit compute clusters for high-performance simulations

Fear and Foxes: An Educational Primer for Use with "Anterior Pituitary Transcriptome Suggests Differences in ACTH Release in Tame and Aggressive Foxes".

The way genes contribute to behavior is complicated. Although there are some single genes with large contributions, most behavioral differences are due to small effects from many interacting genes. This makes it hard to identify the genes that cause behavioral differences. Mutagenesis screens in model organisms, selective breeding experiments in animals, comparisons between related populations with different behaviors, and genome-wide association studies in humans are promising and complementary approaches to understanding the heritable aspects of complex behaviors. To connect genes to behaviors requires measuring behavioral differences, locating correlated genetic changes, determining when, where, and how these candidate genes act, and designing causative confirmatory experiments. This area of research has implications from basic discovery science to human mental health