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Effects of Varying Habitats on Competition between Endangered San Joaquin Kit Foxes (Vulpes macrotis mutica) and Coyotes (Canis latrans): Author: Nelson, Julia Lynn; Date: 2005-12-15; Program: Biological Sciences; Abstract: Coyotes (Canis latrans) are the primary predator of endangered San Joaquin kit foxes (Vulpes macrotis mutica). Coyotes often associate with coverrich habitats while kit foxes use grasslands, alkali shrublands, and urban environments. Effects of varying habitats on coyote and kit fox competition are relatively unknown. I assessed exploitation and interference competition between coyotes and kit foxes in grassland and shrubland habitats to determine if kit foxes are niche displaced by coyotes. I evaluated habitat and spatial partitioning, diet, and prey abundance of kit foxes and coyotes, as wel...; Download File | View full details

Behavioral Ecology of the Striped Hyena (Hyaena hyaena): Author: Wagner, Aaron Parker; Date: 2006-05-15; Program: Biological Sciences; Abstract: Relatedness is often estimated from microsatellite genotypes that include null alleles (Dakin & Avise 2004). When null alleles are present, observed genotypes represent one of several possible true genotypes. If null alleles are detected, but analyses do not adjust for their presence (i.e., observed genotypes are treated as true genotypes), then estimates of relatedness and relationship can be incorrect. The number of loci available in many wildlife studies is limited, and loci with null alleles are commonly a large proportion of data that cannot be discarded without substantial loss of po...; Download File | View full details

Behavioral Responses of Elk (Cervus elaphus) to the Threat of Wolf (Canus lupus) Predation: Author: Winnie, John Arthur, Jr.; Date: 2006-05-15; Program: Biological Sciences; Abstract: We studied individual and herd level behavioral responses of elk to spatial and temporal variation in the risk of predation by wolves over three winters in the Upper Gallatin drainage, Montana. Within a given drainage, elk of both sexes moved into or closer to protective cover (timber) in response to wolf presence. Cow elk responded to elevated risk by increasing vigilance in exchange for foraging, and large mixed (cow, calf, spike) herds substantially decreased in size. In contrast, when wolves were present, bulls did not increase vigilance levels, nor decrease feeding, and small bull-only gr...; Download File | View full details

Elk (Cervus elaphus) Vigilance Levels in Response to Predation Risk from Wolves (Canis lupus): Author: Liley, Stewart Grayson; Date: 2007-05-15; Program: Fish and Wildlife Management; Abstract: Many studies have shown that levels of antipredator vigilance are sensitive to variation in prey attributes, such as age, sex and group size. It is also well established that vigilance is sensitive to environmental effects, such as the presence of cover. In contrast, little is known about the sensitivity of vigilance to variation in factors associated with the predator itself, such as proximity, the size of the threatening group, and cues about motivation to hunt. Finally, little is known about the relative importance of these three classes of variables (predator, prey, and environment), or ab...; Download File | View full details

Risk effects in elk (Cervus elaphus): behavioral and nutritional responses to wolves and environmental conditions: Author: Christianson, David Alan; Date: 2008-05-15; Program: Ecology and Environmental Sciences; Abstract: Until recently, predators have been though to regulate prey primarily through direct predation, in ecosystems where top down effects have been shown to be important. However, experiments and recent empirical observations show that the costs of antipredator responses in individuals that successfully avoid predation can exert equal or larger driving forces on population dynamics than the numerical effect of direct predation. Such a mechanism has not been explored in a large terrestrial vertebrate. I explored the antipredator responses of elk (Cervus elaphus) to wolves (Canis lupus) in the Upper ...; Download File | View full details

The spatial ecology and mating system of black bears (Urus americanus) in New Mexico: Author: Costello, Cecily Marie; Date: 2008-08-15; Program: Fish and Wildlife Biology; Abstract: In summary, our results show that high rates of male dispersal and female philopatry combine to create a spatial genetic structure that generates low rates of inbreeding and little need for kin discrimination among potential mates. Thus, evidence supports the hypothesis that inbreeding avoidance is achieved by means of male-biased dispersal in black bears. Our results also suggest the general pattern of male-biased dispersal is modified by competition for mates or resources....; Download File | View full details

The effects of supplemental feeding on stress hormone concentrations in elk: Author: Patrek, Victoria Elizabeth; Date: 2009-05-15; Program: Biological Sciences; Abstract: On twenty-two feedgrounds in western Wyoming, elk (Cervus elaphus) are provided with supplemental feed throughout the winter. Brucellosis seroprevalence of feedground elk is 26% whereas other elk in the Greater Yellowstone Ecosystem have historically had a brucellosis seroprevalence of 2-3%. The aggregation of elk during peak transmission allows brucellosis to persist in the feedground populations. In addition to creating the opportunity for disease transmission, the aggregation of elk on feedgrounds may have detrimental physiological effects. Studies have shown that chronically high stress ho...; Download File | View full details