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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Ecology of coyotes (Canis latrans) in the greater Detroit area of southeastern Michigan

Dodge, William B., Jr. 24 May 2016 (has links)
<p>Coyote distribution and habitat use, diet and foraging behavior, and space use patterns were investigated in the greater Detroit area of southeastern Michigan. We found evidence of coyotes on 24 of 30 (80%) suburban and 7 of 11 (64%) urban plots. Overall fifty-eight percent of coyote evidence was found within edge habitats, with den sites and tracks the only types of evidence found strictly in interior habitats. Land cover around evidence points included more wooded land cover than expected in suburban areas, suggesting the importance of tree cover for coyote occupancy, and more open space and wooded land cover than expected in urban areas, highlighting their avoidance of heavily populated areas. Coyote diet was assessed through identification of remains of food items recovered in coyote scat. White-tailed deer, eastern cottontail rabbit, and small rodents were the most consumed prey in both urban and suburban areas. Coyote consumption of white-tailed deer biomass was 7.2% greater than expected in suburban areas and 10.0% less than expected in urban areas and the difference was significant (<i>P</i> &lt; 0.004). More white-tailed deer, raccoon, and woodchuck biomass was consumed compared to other studies, likely due to high use of road-kill. In suburban areas, coyote selection for road-killed white-tailed deer was positive regardless of white-tailed deer or rabbit abundance. Coyotes in urban areas used a foraging strategy that incorporated both prey selection and switching, with no strong discernable pattern. Radio-telemetry technology was used to gather relocations of coyotes for analysis of home range and cores areas frequented by coyotes. Smaller home ranges were made up of greater proportions of urban land than natural land cover, although there was variation. Core areas were dominated by relatively large patches of natural land cover and had greater connectivity compared to home range areas. Radio-telemetry data suggested that coyotes were selective in their use of space, avoiding urban land in favor of natural land cover. </p>
112

Determining habitat suitability for the western gray squirrel and eastern gray squirrel in California| Predicting future ranges with Maxent and ArcGIS

Creley, Carly McKean 26 July 2016 (has links)
<p> The main goals of this study were to map the current distribution of the invasive eastern gray squirrel in California as of 2016, to project the potential future geographic range of the species, and to identify areas where the future range of the eastern gray squirrel is likely to overlap the range of the native western gray squirrel. Location data were obtained from museum specimens, wildlife rehabilitation centers, a roadkill database, and research-grade citizen observations. Ecological niche models were created with Maxent, while range and habitat suitability maps were produced with ArcGIS software. Populations of eastern gray squirrels are currently concentrated around Sacramento, the San Francisco Bay, Monterey, and Bellota. The highest priority areas for control and eradication are areas of western gray squirrel habitat near existing eastern gray squirrel populations, including both peninsulas of the San Francisco Bay, areas near Santa Cruz, Oakland, Santa Rosa, and the Monterey Peninsula.</p>
113

Management and regulation of local subsistence hunting in North Alaska

Huntington, Henry P. January 1991 (has links)
No description available.
114

River habitats in the UK : distribution, drivers for maintenance, and impacts of management

Fox, Peter J. A. January 2000 (has links)
No description available.
115

Predicting the distribution of Eurasian badger (Meles meles) setts

Wright, Amanda January 1997 (has links)
No description available.
116

An economic measure of nonconsumptive wildlife values : implications for policy analysis

Richards, Merton T.(Merton Taylor),1939- January 1980 (has links)
In the last 200 years the importance of wild animals to man has taken two distinct forms: the use of creatures that provide 'game" for sport hunting, and the existence of value for the scientific or aesthetic appreciation of wildlife. Further, the relative strength of these two uses has shifted over time. It appears that a recent, significant growth in the number of people who hold high value for nongame uses of wildlife has taken place. The traditional emphasis of state wildlife management agencies has been on the production of game species in response to the overwhelming financial support from sportsmen. It is often argued that game management contributes to the welfare of nongame species. The reverse is also true, and sportsmen's interests could be served by a wildlife program giving greater weight to nongame activities. Through a modest redefinition of objectives the Arizona Game and Fish Department could effect a political alignment of game (consumptive) and nongame (monconsumptive) wildlife interests. This study is based on a federally funded research project in which the nonconsumptive uses and values of wildlife are being assessed. In particular, the purpose of this study is two-phased: to estimate the economic benefits to nonconsumptive wildlife users from viewing, studying, and photographing wild animals, and to relate these benefits to the political process in which the Arizona Game and Fish Department obtains its funding and political support. A modification of the travel-cost technique was used in this study to estimate economic benefits obtained by nonconsumptive wildlife users. Importantly, an explicit measure of the monetary value of travel time is empirically derived, providing improved benefit estimates. Visitors to seven wildlife viewing locations in Southeast Arizona responded to a mailed questionnaire at a rate of 86 per cent to provide a voluntary sample of more than 600 wildlife enthusiasts. An array of social and economic data were gathered for individuals and households. Respondents can be generally characterized as highly educated, affluent, middle aged, metropolitan residents. Using multiple regression analysis, demand functions were estimated for each household visiting three representative sites. Consumers' surplus values were then estimated for each site, incorporating an explicit measure of the value of travel time. These values compare favorably to consumers' surplus values estimated for hunting and fishing activities in Arizona. The results of the economic analysis performed in this study are primarily methodological. They are suggestive, however, of considerable political influence regarding wildlife management in Arizona. Importantly, a method exists for measuring the economic value or social welfare of the nonconsumptive use of wildlife. Such measures, widely assessed, could permit the comparison of economic values between consumptive and nonconsumptive wildlife uses and the evaluation of the associated change in consumer welfare resulting from alternative management activities. Based on the estimates of the number of people for whom nonconsumptive wildlife appreciation is important, there is reason to expect that significant political involvement in wildlife management issues will occur. These findings portend a major opportunity for the Arizona Game and Fish Depar went in terms of operational budgets and continued wildlife management authority in the state. Several recommendations are made to the Arizona Game and Fish Department, including improvement in their public image and greater political involvement with nonconsumptive wildlife interest groups.
117

Contextual fit of residential structures in forested landscapes

Tibbels, Stephen Brett, 1960- January 1990 (has links)
Contextual fit relationships have been examined in many different man-made environments. To date, however, investigation of contextual fit relationships between manmade structures and natural settings has been minimal. The present research examines contextual fit of residential structures to their forested settings. Structure color contrast to setting was found to be inversely related to both perceived fittingness and aesthetic appeal. A positive relationship between fittingness and aesthetic appeal was uncovered. The bearing that these findings can have on visual quality, preservation of forest setting sense of place, and quality of life, is discussed.
118

Habitat use and life history of the Mount Graham red squirrel

Froehlich, Genice Frances, 1953- January 1990 (has links)
I studied habitat use by 9 radio-collared Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis) during the summers of 1988 and 1989 in the Pinaleno Mountains, Arizona. My 2 study areas represented an Engelmann spruce (Picea engelmannii)/corkbark fir (Abies lasiocarpa) association on High Peak and a Douglas-fir (Pseudotsuga menziesii) association on Merrill Peak. I trapped 9 squirrels in 33,400 trap hours, and calculated the seasonal home range for 4 animals, 2 in each study area. Hidden density was 0.54 and 0.2 middens/ha, respectively, but seasonal home range size (x = 3.62 ha) did not vary between habitats. Squirrel numbers decreased on both study areas between 1988 and 1989. I concluded that preference for habitat characteristics in midden areas explained lower densities in the mixed conifer vegetation. Squirrels fed mainly on cones and mushrooms, depending on season and availability. Mt. Graham red squirrels may breed twice/year.
119

Fences as barriers to desert mule deer along canals in central Arizona

Carmichael, Gregory Bruce, 1965- January 1991 (has links)
Water associated with the Central Arizona Project (CAP) and its delivery systems attract wildlife. Crossing structures, alternate water sources, and fences have been built to reduce wildlife mortality associated with canals. Their effectiveness, however, has not been evaluated. I assessed the effectiveness of a woven wire and an electric fence located on the CAP and Tonopah Canals, respectively. The purpose of these fences was to prevent desert mule deer (Odocoileus hemionus crooki) from entering canals. I established track plots to quantify differences in deer use between areas separated by the canals. I used line intercept transects to examine differences in the vegetation between the north and south sides of the CAP. Both types of fences were effective in keeping deer out of the canal. The north side of the CAP had more deer use and more ground cover than the south side. If future offshoot canals are small, they may be left unfenced, if follow-up studies reveal no significant wildlife mortality.
120

Habitat selection by mountain sheep in Mojave Desert scrub

Berner, Louis Robert, 1963- January 1992 (has links)
I identified habitat use by 12-18 mountain sheep (Ovis canadensis nelsoni) in a 320-ha enclosure between June 1990 and June 1991 on the Desert National Wildlife Refuge, Nevada. The enclosure included 9 vegetation associations and 5 slope classes. I used a non-mapping technique and line transects to determine availability of vegetation associations and slope classes, and species composition, respectively. I determined use of habitats by mountain sheep with instantaneous sampling. Mountain sheep used midslopes and draw associations on the west side of the study area, and slope classes of 36-80% more than expected based on availability. I tested Hansen's (1980) habitat evaluation model on the study area. The model was >98% accurate in predicting mountain sheep use of habitat. Habitat use by mountain sheep in the enclosure was similar to habitat use of free-ranging mountain sheep.

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