Theses and Dissertations at Montana State University (MSU)
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Item Spotted hyaena survival and density in a lion depleted ecosystem : the effects of competition between large carnivores in African savannahs(Montana State University - Bozeman, College of Letters & Science, 2015) M'soka, Jassiel Lawrence Juma; Chairperson, Graduate Committee: Scott Creel; Scott Creel, Mathew S. Becker and James Murdoch were co-authors of the article, 'Ecological and anthropogenic effects on the density of migratory and resident ungulates in a human-inhabited protected area' submitted to the journal 'African journal of ecology ' which is contained within this thesis.; Scott Creel, Mathew S. Becker and Egil Droge were co-authors of the article, 'Spotted hyaena survival and density in a lion depleted ecosystem: the effects of competition between large carnivores in African savannahs' which is contained within this thesis.Competition is considered an important factor for large carnivore population dynamics, but the manner in which interspecific competition impacts these species are not well understood. This lack of knowledge is due to the ongoing declines of large carnivores, the loss of intact large carnivore guilds, the complexity of competitive relationships and how they can be impacted by ecological and anthropogenic factors. In light of rapid declines of carnivore populations across the globe, understanding how interspecific competition limits large carnivores is an important component for the management and conservation of these species. Using data from 233 individuals in five clans and capture-recapture robust design models we estimated the survival and density of spotted hyaena in 5 clans in the Liuwa Plain, where their main competitor, the African lion was reduced to a single individual. We tested for the effects of settlements, prey density, competition with lions and hyaena clan size on the mean hyaena survival. The average population size during the duration of study was 151.2 + or = 5.9(SE) individuals. Population size fluctuated through time with the seasonal fluctuations of the main prey species, the blue wildebeest. Mean annual survival across all age classes was 0.93 (95%CI: 0.39 - 0.99). We found no detectable effects of variation in hyaena clan size, prey density, local variation in utilization by lions, or proximity to people on survival. We also estimated the densities of wildebeest, oribi and zebra, the main prey species for the carnivores in the system using distance sampling methods. We tested for the effects of variables in three classes: environmental (year, season, vegetation, grass height, burn, water presence), predation risk (hyaena density), and anthropogenic (distance to park boundary and settlements). Densities ranged from 6.2 - 60.8 individuals km superscript -2 for wildebeest, 1.1-14.5 individuals km superscript -2 for oribi, and 1.8-8.1 individuals km superscript -2 for zebra. Results reveal resource partitioning among ungulate species and indicate that predation risk and proximity to humans affect ungulate distributions with implications for managing migrations in the Greater Liuwa Ecosystem. They suggest that the maintenance of native prey populations allows coexistence between humans and large carnivores in Liuwa Plain National Park.Item Factors affecting the distribution and abundance of carnivores and their ungulate prey across a communally owned rangeland in Kenya(Montana State University - Bozeman, College of Letters & Science, 2012) Schuette, Paul Anthony; Chairperson, Graduate Committee: Scott Creel; Aaron Wagner, Meredith Wagner and Scott Creel were co-authors of the article, 'Occupancy patterns and niche partitioning within a diverse carnivore community exposed to anthropogenic pressures' in the journal 'Biological conservation' which is contained within this thesis.; Scott Creel was a co-author of the article, 'Spatiotemporal niche partitioning among large carnivores, ungulates, people, and livestock in Southern Kenya' which is contained within this thesis.; Scott Creel and David Christianson were co-authors of the article, 'Factors affecting the distributions of native ungulates and livestock in Kenya's Rift Valley' in the journal 'Conservation biology' which is contained within this thesis.; Scott Creel and David Christianson were co-authors of the article, 'African lion abundance and space use in relation to a seasonally migrating human pastoralist community' in the journal 'Conservation biology' which is contained within this thesis.Carnivore and native ungulate populations are in decline inside and outside of government-protected areas in Africa due to habitat fragmentation, conversion of rangeland to farmland, and conflict. Though government-protected areas are an important component of conservation and management policy, it is also important to include landscapes that vary in their degree of protection and human land use. These mixed-use landscapes may provide valuable insight into patterns that promote coexistence among carnivores, native ungulates, and people. From 2008-2011, we examined distributions and abundances of carnivores and their ungulate prey across a communally-owned rangeland in the southern Rift Valley of Kenya. Here, the local Maasai community moves seasonally with their livestock across areas set aside for human settlement, livestock grazing, and a community conservation area. Camera surveys revealed a diverse carnivore community (21 species), which includes all native apex carnivores. Occupancy models revealed patterns of spatial and temporal niche partitioning in response to environmental conditions and anthropogenic pressures. Apex carnivore and native herbivore occupancies were sensitive to the proximity of water, the dry season, and distance to human settlements. In general, most carnivore and native herbivores responded to some form of human land use. Animal counts and distance sampling indicated livestock densities were nearly three times higher than total native ungulate densities, however, native ungulate densities were comparable to many government-protected areas. Selection of different habitats and land use types promoted coexistence between domestic and native ungulates. Zebra, wildebeest, and cattle (obligate grazers) densities were sensitive to a severe drought, but only wildebeest failed to rebound to pre-drought levels the following year. Behavioral follows of radio-collared lions (4F, 2M) revealed a local lion density of 0.136 individuals/km ², comparable to many government-protected areas. Lion groups altered their space use in response to seasonal movements of people, a pattern that likely explains low levels of local conflict. Overall, the combination of an unfenced, heterogeneous landscape and a land use system based on temporary settlements, seasonal grazing areas, and a community conservation area, allows apex carnivores, a diverse carnivore community, and their native ungulate prey to coexist at high densities with people and livestock.Item Using noninvasive genetic sampling methods to estimate demographic and genetic parameters for large carnivore populations in the Rocky Mountains(Montana State University - Bozeman, College of Letters & Science, 2012) Sawaya, Michael Allen; Chairperson, Graduate Committee: Steven Kalinowski; Toni K. Ruth, Scott Creel, Jay J. Rotella, Jeffrey B. Stetz, Howard B. Quigley, and Steven T. Kalinowski were co-authors of the article, 'Evaluation of noninvasive genetic sampling methods for cougars in Yellowstone National Park' in the journal 'Journal of wildlife management' which is contained within this thesis.; Jeffrey B. Stetz, Anthony P. Clevenger, Michael L. Gibeau and Steven T. Kalinowski were co-authors of the article, 'Estimating grizzly and black bear population abundance and trend in Banff National Park using noninvasive genetic sampling methods' in the journal 'PLoS ONE' which is contained within this thesis.; Anthony P. Clevenger, and Steven T. Kalinowski were co-authors of the article, 'Wildlife crossing structures connect ursid populations in Banff National Park' in the journal 'Conservation biology' which is contained within this thesis.; Steven T. Kalinowski, and Anthony P. Clevenger were co-authors of the article, 'Gene flow at wildlife crossing structures in Banff National Park' in the journal 'Molecular ecology' which is contained within this thesis.Healthy carnivore populations are important to maintaining ecosystem balance, but many species are declining globally at disturbing rates due to anthropogenic causes. To effectively manage and conserve carnivores, wildlife managers must be able to obtain reliable estimates of population parameters. Noninvasive genetic sampling (NGS) methods such as hair or scat collection offer new and exciting alternatives to traditional carnivore research methods involving capture, drugging, and handling of animals; however, the potential of NGS methods to answer applied ecological questions has not been fully realized. The main objective of my doctoral research was to develop and apply NGS methods to estimate demographic and genetic parameters for large carnivore populations in the Rocky Mountains. First, I evaluated two NGS methods, hair snares and snow tracking, for cougars (Puma concolor) in Yellowstone National Park. I developed a method to collect hair while following cougar tracks in snow to bed sites and natural hair snags (e.g. thorn bushes, branch tips) from which I demonstrated that samples collected using NGS can provide reliable information on cougar population abundance. Next, I compared the ability of two NGS methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bears (U. americanus) in Banff National Park. I found that bear rubs performed better than hair traps for estimating grizzly bear abundance and population growth rates, whereas hair traps worked better than bear rubs for black bears. I then used NGS to examine demographic and genetic connectivity at wildlife crossing structures along the Trans-Canada Highway that bisects Banff National Park. I compared genetic data collected from the bear populations surrounding the highway to data collected at the crossing structures using a novel hair sampling system. This comparison allowed me to show that wildlife crossing structures provided demographic connectivity for bear populations and maintained sufficient gene flow across the highway to prevent genetic isolation. In short, I have demonstrated the power of using an array of NGS methods, alone or in combination, to estimate abundance, gene flow, genetic structure, migration, and population growth rates for large carnivores in the Rocky Mountains.