Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--Washington State University, August 2007. / Includes bibliographical references (p. 31-33).

The long-tailed duck (Clangula hyemalis; hereafter LTDU) breeds on the arctic tundra across Alaska and Canada and winters south of the ice edge along the Pacific and Atlantic coasts, as well as on the Great Lakes. Data suggest that LTDU populations are in decline and, as a result, efforts have been made to better understand their population distributions through satellite telemetry studies. Radio-marked LTDUs from previous studies have shown very little use of Lake Michigan, even though aerial surveys indicate that large concentrations of this species overwinter there. LTDUs using Lake Michigan face a host of conservation issues, such as risk of exposure to type E botulism, bycatch in fishing gear, wind energy development, and a changing ecosystem. Using satellite telemetry, I documented migratory routes and habitat use of LTDUs wintering on Lake Michigan. LTDUs on Lake Michigan were captured via night-lighting and 10 LTDUs were surgically implanted with Telonics platform transmitter terminals (PTTs). Six (60%) radio-marked LTDUs provided information on Lake Michigan habitat use, while only 3 (30%) provided information on migratory routes. The average distance from shore of individual radio-marked LTDUs on Lake Michigan varied from 1.4-7.8 km and average water depths at these locations varied from 16.8-27.7 m during daylight hours. At night, radio-marked LTDUs were located further offshore (averaging 7.3-16.5 km) and at deeper water depths (averaging 59.6-74.8 m). LTDUs tended to move south on Lake Michigan as winter progressed, and then relocated to the north basin before spring migration. James Bay and Hudson Bay were the primary stopover sites during spring and fall migration, and the province of Nunavut, Canada was used during the breeding season. After breeding, radio-marked LTDUs traveled north to waters near Adelaide Peninsula, Nunavut, Canada. Only one radio-marked LTDU provided information for a full migration cycle and it returned to winter on Lake Michigan. Two methods, ocular and molecular examination of the alimentary canal, were used to determine the diets of LTDUs on Lake Michigan. A total of 16 LTDU carcasses were donated by hunters for diet determination. An esophageal, small intestine, and cloacal swab were collected from each carcass for molecular determination of prey species through qPCR analysis. The esophagus of each carcass was then removed and prey items determined to lowest taxonomic level using a dissection microscope (10X Ocular). Molecular methods detected more prey species (4) than ocular methods (1), so molecular methods show promise as a non-lethal means to determine LTDU diets. Quagga mussel (Dreissena rostriformis bugensis) was the primary prey item with 100% occurrence. Diporeia spp., yellow perch (Perca flavescens), and alewife (Alosa pseudoharengus) were also detected, suggesting that LTDUs are opportunistic feeders. An in-person hunter harvest survey was conducted at Two Rivers, Wisconsin, to determine how environmental variables influenced harvest, to estimate harvest rates, and to gather hunter input regarding hunting regulations on Lake Michigan. Results indicate that LTDUs made up 97% of the total harvest, and that hunters averaged 3.8 LTDUs per day. Harvest of LTDUs was positively correlated with hunter numbers, and wave height was the most influential environmental variable affecting hunter numbers. Results suggest that few hunters go out when wave heights exceed 1.5 m. Hunters indicated that they would prefer a later or longer season on Lake Michigan, and that they were concerned about LTDU populations. Information from this study aids resource managers and scientists as they seek to determine basic information regarding LTDUs that winter on Lake Michigan. Migratory data is important in determining if the eastern population of North American LTDUs should be managed based on wintering and/or breeding distribution, while habitat use information will aid in mitigating impacts from fishing bycatch and future wind energy development. Habitat use and diet data will benefit resource managers and scientists seeking to determine where and how LTDUs may become exposed to avian botulism type E. Diet data will also aid in determining how LTDU diets are changing due to the altered ecosystem in Lake Michigan from introduced and invasive species. Moreover, results from the diet portion of this study suggest that molecular methods, that can be used non-lethally or in combination with lethal methods, show promise for determining LTDU prey items. Information on harvest rates can be used in determining harvest impacts, while hunter perceptions may aid resource managers as they make decisions regarding season structure and limits for LTDUs on Lake Michigan.

This study of deer ecology was conducted from January, 1975, to May, 1976, in the East Kootenay region of British Columbia. Plant communities within the annual range of a population of white-tailed deer were classified into habitat types and analysed for species composition, productivity and forage utilization. Relative levels of use of winter habitat types were determined from track and pellet group counts. Use of summer habitats was determined subjectively from ground and aerial surveys. Movements associated with changes in habitat use and season were documented by observation and radio tracking of marked individuals. Forest succession over much of the winter range was found to have resulted in substantial decreases in availability of herbaceous and deciduous browse, causing quantitative and qualitative changes in the diet of this deer population. To compensate for this situation deer feeding activity was concentrated in the open habitat types which provide maximum quantities and qualities of forage. However, snowdepth in one winter was found to reach levels which prevented deer from exploiting these areas and concentrated them in areas where a maturing overstory reduced snowpack. The impact of concentration in shelter types with consequent reduction of available food, compared to a very mild winter, was an apparent 30% reduction in the juvenile:100 adults ratio the following spring. Summer distribution also appeared to be affected by large-scale forest succession which has produced a pattern of widely scattered, small openings. These were found mainly along water courses or rocky slopes at mid- elevations on the west side of the Rock Mountain Trench. Deer density was low throughout the summer range, but preference was observed for the open areas just described. Spring dispersal from the winter range was related to snow melt and green-up of vegetation, particularly cultivated alfalfa fields. Summer home ranges were relatively small and summer movements limited. The average distance travelled to summer range by nine deer was greater than that reported elsewhere in the literature and may be related to summer range habitat condition. Fall movements were apparently stimulated by lasting snowfall. Although density of deer on the winter range varied greatly between years, home range loyalty was found to be relatively high. / Science, Faculty of / Zoology, Department of / Graduate

Vegetation and soils were evaluated on a black-tailed prairie dog (Cynomys ludovicianus) colony and adjacent non-disturbed mixed-grass prairie in central South Dakota. The study’s objectives were 1) determine differences in plant species diversity and richness, and selected soil quality parameters between prairie dog colonies and adjacent non-disturbed sites, and 2) evaluate impacts of prairie dogs on water infiltration rates. Three soil series were evaluated representing three ecological sites (Opal, Cabba, and Wayden). Plant species richness was higher on the Control on Opal soils, while being lower on the Control on Cabba soils. Lower soil pH and higher nitrate concentrations were found on the prairie dog town for Opal and Cabba soils near the soil surface, close to the prairie dog mounds. These findings show prairie dog impacts on soil parameters can vary across different soil types, which can affect the diversity and richness of vegetative communities within prairie dog colonies.

No description available.

Identifying factors influencing kill rates or predation risk is crucial to relate predator effects on prey populations. In multi-predator landscapes, some predators may also perceive predation risk which may not only influence their distributions but also their effects on prey populations across landscapes. In the Upper Peninsula of Michigan, USA white-tailed deer (Odocoileus virginianus) exist in a multi-predator landscape which includes black bears (Ursus americanus), bobcats (Lynx rufus), coyotes (Canis latrans), and gray wolves (C. lupus). The objectives of this research were to examine spatial relationships among predators and their prey by identifying: 1) competition between wolves and coyotes, 2) factors influencing kill rates of predators, and 3) predator-specific predation risk for white-tailed deer fawns. We quantified the degree of temporal, dietary, and spatial overlap of wolves and coyotes at the population level to estimate the potential for interference competition and identify the mechanisms for how these sympatric canids coexist. We observed significant overlap across resource attributes yet the mechanisms through which wolves and coyotes coexist appear to be driven largely by how coyotes exploit differences in resource availability in heterogenous landscapes. We examined how heterogeneity in landscapes, search rate, and prey availability influence the time between kills for black bears, bobcats, coyotes, and wolves. Spatial heterogeneity in prey availability appeared to be a unifying extrinsic factor mediating time-to-kill across predators, potentially a consequence of more frequent reassessments of patch quality, which can reduce kill rates. We used white-tailed deer fawn predation sites to identify predator-specific predation risk with consideration for active predator occurrence, adult female white-tailed deer occurrence, linear features which may influence prey vulnerability, and habitat characteristics including horizontal cover and deer forage availability. Predator occurrence alone was a poor metric for predation risk. We identified differing landscapes of risk among ambush and cursorial foraging strategies which were more important for defining spatial variation in predation risk than predator density. These findings suggest that in a multi-predator landscape some predators may benefit from greater landscape heterogeneity due to availability of niche space, even though resource heterogeneity reduced predator efficacy and habitat complexity reduced predation risk for prey.

White-tailed deer (Odocoileus virginianus) are an important ecological, social, and economic resource in Mississippi. Studies have been conducted on expenditures by white-tailed deer hunters, but none have administered a research-based, economic impact assessment for white-tailed deer in Mississippi. The economic impacts and associated values of white-tailed deer in Mississippi through a selfministered mail questionnaire were examined to collect white-tailed deer hunter expenditure data during the 2003/2004 hunting season. Expenditures of white-tailed deer hunters were obtained from a mail survey (N = 1,257, 38.6% response rate) and were used in an input-output model to determine economic impacts for the State. Economic impacts generated from white-tailed deer hunting expenditures totaled $951.1 million for the 2003/2004 white-tailed deer hunting season. The value added component of the economic impact totaled $686.7 million and supported 43,964 full- and part-time jobs.

No description available.

M.S.