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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

Territoriality and habitat selection of feral pigs on Fort Benning, Georgia, USA

Sparklin, William DeRoche. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Contents viewed on November 25, 2009. Title from author supplied metadata. Includes bibliographical references.
112

The effects of patch shape and connectivity on nest site selection and reproductive success of the indigo bunting

Weldon, Aimee Jean, January 2004 (has links)
Thesis (M.S.)--North Carolina State University, 2004. / Title from PDF t.p. (viewed on Dec. 16, 2005). Includes vita. Includes bibliographical references.
113

The Influence of Habitat Features on Selection and Use of a Winter Refuge by Manatees (Trichechus manatus latirostris) in Charlotte Harbor, Florida

Barton, Sheri L. 11 May 2006 (has links)
Investigating alternate winter refuges for Florida manatees is increasingly important as sustained warm-water discharges from industrial and some natural sites becomes more uncertain. This study examined habitat features of possible importance to manatees by comparing a winter refuge in Charlotte Harbor, FL (the Matlacha Isles canal system) to two nearby, seemingly similar sites that are not frequented by manatees during winter. Water temperature, salinity, boat traffic, canal depth, and tidal flushing were assessed at these sites. Additionally, this study examined when and how manatees use the Matlacha Isles refuge by documenting movements, habitat use, and behaviors of manatees during the winters of 1999/2000 through 2001/2002. Water temperatures had a profound influence on manatee selection of Matlacha Isles over the two comparison canal systems. Matlacha Isles did not experience the sudden drops in water temperature following cold fronts, extreme low temperatures, or long periods of temperatures below manatees’ reported thermal tolerance of 18-20 oC that were recorded in Matlacha Pass (ambient) and the two comparison canal systems. Heat retention within Matlacha Isles may be associated with greater water depth and lower tidal flushing. Salinity and boat traffic did not seem to influence site selection by manatees. During moderately cold weather, manatees occupying Matlacha Isles forage at night in nearby Matlacha Pass and return early in the morning to Matlacha Isles, where they primarily rest all day. Neither tidal state nor boat traffic levels affected manatee travel patterns into or out of Matlacha Isles. Manatees may passively thermoregulate in the warmer waters of Matlacha Isles during the day (when they are inactive) and sustain their body temperatures at night through the heat generated during traveling to feeding sites and during ingestion (chewing) and digestion. During extreme or prolonged cold weather, Matlacha Isles provides inadequate warmth for manatees; during such times, most of them travel to a power plant on the Orange River, approximately 50 kilometers away. Findings from this study may inform resource managers as they consider attributes manatees find desirable or necessary in winter. Such information will help managers create new or enhance existing winter refuges to protect manatees.
114

Habitat selection, movement patterns, and demography of common musk turtles (Sternotherus odoratus) in southwestern Québec

Belleau, Pascale. January 2008 (has links)
I studied the common musk turtle (Sternotherus odoratus) at the northern limit of its range at Norway Bay, Quebec, from April to October 2006. Common musk turtles are habitat specialists and are selective of their habitats at the study-area and home-range scales. Beaver ( Castor canadensis) lodges were preferred at the study-area scale. Common musk turtles also preferred beaver lodges, emergent wetlands, aquatic beds with floating and submerged vegetation as well as rocky shores at the home-range scale. At the location scale, common musk turtles chose shallower and cooler sites that contained more logs and submerged vegetation than the sites available at random. There was no significant effect of sex on habitat use at the location scale. There was no significant difference in mean daily movements between the sexes during the active season. However, sex and month probably interact together to influence the mean distance traveled daily by common musk turtles in Norway Bay. Males appeared to move more than females in May, July, and October. Females appeared to move more daily than males in August and September. Neither sex appeared to move more daily in June. However, our small sample size did not allow us to conduct a conclusive analysis. The mean home-range area was 23.9 ha and was not different between sexes. I estimated a density of 4.1 turtles/ha and a sex ratio of 1.7M: 1F. The population includes 59.6% males, 35.8% females, and 4.6% juveniles. Adults ranged from 77 mm to 133 mm in carapace length.
115

Habitat selection by sympatric ungulates in an agricultural landscape : implications for disease transmission and human-wildlife conflict

2013 January 1900 (has links)
As areas of agricultural production expand worldwide, complex zones of wildlife-agriculture interface present numerous benefits and challenges to farmers and wildlife managers. In western Canada, free-ranging elk (Cervus canadensis), mule deer (Odocoileus hemionus), and white-tailed deer (Odocoileus virginianus) make frequent use of cereal, oilseed, and pulse crops. However, cervid use of annual crops presents substantial socio-economic concerns for producers. Additionally, use of crops may facilitate cervids co-mingling and increase the risk of intra- and inter-specific transmission of chronic wasting disease (CWD). The purpose of my thesis research was to determine the key environmental factors influencing the selection of agricultural crops by elk, white-tailed deer, and mule deer, analyze overlap in species’ selection, and develop predictive models to identify the spatial distribution of crop damage risk. In this study, I analyzed 19,069 damage claims paid by Saskatchewan Crop Insurance Corporation to Saskatchewan farmers for confirmed losses to annual crops (cereals, oilseeds, pulses) from 2000-2012 by elk, mule deer, and white-tailed deer. These data were used to conduct species-specific ecological niche factor analyses (ENFAs), which relate habitat variables within damaged sites to that of the surrounding landscape. The key habitat variables influencing selection of annual crops were then incorporated into resource selection probability function (RSPF) models. These models characterize and predict the probability of crop damage by elk, mule deer, and white-tailed deer, and each possible dual species combination. By integrating damage probability values and historical monetary values of regional crop production, I evaluated the risk of annual crop damage by each of the three species, and dual species combinations, across all sections of agricultural land in Saskatchewan. The ENFAs revealed that elk and white-tailed deer selected for areas where a high proportion of farmland is seeded to oats, barley, canola, and alfalfa, while avoiding areas farther from protected areas, with a high density of paved or unpaved roads and a high proportion of open grassland. Alternately, mule deer favoured open grasslands, shrublands, and areas with a greater density of streams or water bodies, while avoiding areas where a high proportion of farmland is seeded to oats, canola, flaxseed, wheat, and barley. Areas at highest risk for annual crop damage by elk bordered the northern edge of the study area; mule deer damage risk was highest in south-western and central Saskatchewan; while white-tailed deer damage risk was highest in north-eastern and north-central areas of the province. Identifying these specific associations between landscape variables, rates of crop damage, and associated species overlap may provide an important opportunity for agencies to develop cooperative management strategies to efficiently allocate mitigation resources. Efforts to prevent the selection of cereal, oilseed, and pulse crops by free ranging elk, mule deer, and white-tailed deer in Saskatchewan could prove to be a valuable step in not only minimizing crop damage and maintaining wildlife tolerance in rural communities, but also in managing the spread of chronic wasting disease throughout western Canada.
116

Cow elk ecology, movements and habitat use in the Duck Mountains of Manitoba

Chranowski, Daniel John 01 December 2009 (has links)
This study conducted baseline research to determine home range, movements and habitat selection of Manitoban elk (Cervus elaphus manitobensis) in the Duck Mountain (DM) of west-central Manitoba. Cow elk (n =22) were captured by helicopter net-gun and GPS radio-collared in 2005/06. Data was analyzed with ArcView 3.3 for Windows (ESRI). DM elk show selection for deciduous forest and avoidance of roads. Mean 100% MCP home ranges were 127.85 km2 with 95% and 50% adaptive kernel home range sizes of 58.24 km2 and 7.29 km2, respectively. Home range overlap occurs at all times of the year with many elk using farmland. Elk moved the least in late winter. Movements increased in the spring, declined in June with a gradual increase from July to October. Elk had generalized movement in southerly directions. No cow elk dispersed from the study area. Mean estimated calving date was June 3rd and mean estimated breeding date was September 27th. DM elk were found in mature deciduous/mixed-wood forest and shrub/grassland/prairie savannah ecosites but not found within 200 m of a road or water feature more often than expected by random. Elk were found in areas with <10% and >81% crown closure, on middle slopes and variable aspects. Elk displaced from forestry cut-blocks. Only 149 of 79,284 elk locations were within 100 m of a winter cattle operation. Recommendations to mitigate forestry and BTB impacts focus on riparian areas, road management, farming practices and hunting.
117

Habitat suitability of the yellow rail in south-central Manitoba

Martin, Kristen 21 September 2012 (has links)
Little is known about the distribution and habitat suitability of yellow rails (Coturnicops noveboracensis) throughout their breeding range. Yellow rail and vegetation surveys were conducted at 80 wetlands in south-central Manitoba in 2010-2011 to evaluate the effectiveness of repeat-visit, call-broadcast night surveys for detecting this species and habitat associations of this species at the 3-km landscape, patch, and plot scales. Yellow rails were detected at 44% of the study wetlands. Yellow rail detection was imperfect (0.63 in each year), but call-broadcast increased the number of yellow rails detected. Future yellow rail survey efforts should employ call-broadcast and at least three surveys per survey point. Yellow rail presence was positively influenced by the amount of marsh/fen in the landscape and the proportion of rushes at the study wetlands. These characteristics should be considered when identifying potential yellow rail habitat in south-central Manitoba.
118

Habitat selection by breeding American black ducks (Anas rubripes) in northeastern Nova Scotia

Hewitson, Stacy January 1994 (has links)
Habitat selection by breeding black ducks (Anas rubripes) was studied in Antigonish County, Nova Scotia during April-September 1990 and 1991. / Black duck pairs selected deciduous shrub ponds and sparsely vegetated ponds and avoided estuarine marsh and large lake habitat. Hens with broods preferred the deciduous shrub habitat while they avoided large lakes. / Black duck pairs appeared to use the distance to a brood-rearing pond as a cue in site selection. The closer a pond was to a suitable rearing pond the more likely it was occupied by a pair, regardless of food or cover resource availability. Black ducks, however, likely used site attributes such as the perimeter of the pond, the availability of aquatic invertebrates and the relative abundance of alder, willow and dead timber as cues in the selection brood-rearing habitat. / Black duck duckling survival, an estimate of recruitment, was the highest on preferred deciduous shrub ponds. Duckling survival was also higher on ponds with only one brood as opposed to ponds with several broods. / The most productive habitat for black ducks in the Antigonish study area were isolated, deciduous shrub ponds influenced by beaver activity. Black duck population numbers can be enhanced by managing local beaver populations.
119

Nest site selection by the American kestrel, Falco sparverius

Spiegel, Stephen. January 1975 (has links)
No description available.
120

Seasonal Habitat Selection by Resident and Translocated Caribou in Relation to Cougar Predation Risk

Leech, Heather 17 April 2015 (has links)
Mountain caribou, an arboreal lichen-feeding ecotype of woodland caribou (Rangifer tarandus caribou), have been extirpated from much of their historic range. Mountain caribou are federally listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and red-listed by the BC government. Habitat loss and fragmentation of old growth forest is the ultimate cause for population declines. Yet, predation, linked to apparent competition, is the proximate cause for high rates of mortality. One of the most imperiled populations resides in the Purcell Mountains of BC, which was experimentally augmented in 2012 with 19 northern caribou from northern BC. The caribou-predator literature predominantly focuses on the relationship between caribou and wolves (Canis lupus) in northern caribou populations. However, cougars (Puma concolor) have been identified as a major predator of Purcells-South (PS) caribou, yet caribou-cougar interactions remain largely unstudied. I evaluated cougar predation risk in space and time on resident and translocated caribou in the Purcell Mountains. To do so, I determined biologically relevant seasons for resident, donor (i.e. not translocated) and translocated caribou, and cougars. I then used these seasons to investigate seasonal patterns of movement and habitat use between the three groups of caribou and cougars. Next I used resource selection functions (RSFs) to estimate habitat based seasonal variation in predation risk. I used these RSFs to compare the seasonal habitat selection and risk to cougar predation between resident and translocated caribou. Five resident caribou seasons and two cougar seasons were defined. Translocated caribou displayed inconsistent movement behavior with no clear seasonal pattern. Resident caribou remained at high elevations year-round and selected for low risk cougar habitat during the calving season at the home range scale and year-round at the landscape scale. Translocated caribou displayed risky behaviour throughout the study period by traveling to mid to low elevations and habitats selected by cougars. Translocated caribou displayed the same general pattern of elevational movement as their northern conspecifics, spending the majority of their time at lower elevations than resident caribou. Of the 19 translocated caribou, 17 (89%) died during the study, six of which were preyed upon by cougars, two by wolves, and the remainder due to accidents or unknown causes. In summary, translocated caribou did not adopt the predator avoidance or habitat selection strategies of resident caribou. I recommend that future efforts to augment small caribou populations use donor caribou experienced with similar predators and that possess comparable seasonal habitat use to the recipient population. However, because most suitable donor populations are declining, a soft-release of captive-reared mountain caribou might be the best option for mountain caribou recovery efforts. / Graduate / 0366 / 0329

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