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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.
121

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.
122

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.
123

Hierarchical habitat selection by North American porcupines (Erethizon dorsatum) in Parc national du Bic, Québec, Canada

Morin, Patrick January 2002 (has links)
Hierarchical habitat selection was studied in the North American porcupine (Erethizon dorsatum) in Parc National du Bic, Quebec, Canada. To establish the study population, 150 porcupines were captured and immobilized using a mixture of ketamine and xylazine. Different drug doses and injection techniques were tested. Best results were obtained by injecting in the tail muscles, which allowed a 50% reduction in dose relative to reported dosage. Hierarchical analysis of habitat selection revealed that although porcupines are generalists at the landscape scale, they display habitat selection at the home range and individual tree scales. Human-used land and conifer forests were least preferred features of home ranges. Trembling aspen was found to be preferred over other deciduous trees, except for fruit-producing trees, which came out as being even more preferred at the tree scale. This study shows the importance of a multi-scale approach that includes fine-scale selection.
124

Nocturnal Movements and Distributions of Bobcats, Coyotes and Raccoons during Quail Nesting Season

Jhala, Shesh 03 October 2013 (has links)
Northern bobwhites (Colinus virginianus) are a valued game species that have seen massive population declines in the last few decades. This decline has been attributed to many factors including predation, the topic of this study. I examined the habitat selection, nocturnal movement and potential rate of encounter with quail nesting locations by coyotes (Canis latrans), bobcats (Lynx rufus), and raccoons (Procyon lotor) at the Rolling Plains Quail Research Ranch, a private 19 km2 ranch in the Rolling Plains ecoregion of west Texas. My study had 2 objectives: (1) to compare the habitat use of mesopredators in the Rolling Plains to the nesting habitat of bobwhites, and (2) to characterize the nocturnal paths of these mesopredators and measure their overlap with quail nesting locations. I placed GPS collars on 4 bobcats, 7 coyotes and 11 raccoons during the quail nesting seasons of 2009-2011. I used the chi-square test as well as a modified version of the Ivlev’s Electivity Index (1961) to calculate habitat selectivity. I also measured the proximity of the mesopredators and quail nesting locations to roads, water and quail feeders on the ranch. I used fractal analysis to calculate length and tortuosity of nocturnal paths and assessed potential risk to quail nests by determining the intersection rates of mesopredator paths with quail nesting locations. I found that a large difference existed in selectivity of habitat between bobwhite nesting locations and the bobcats and raccoons. Bobwhites selected for the upland grasslands and shrubs and against rocky ridges. Bobcats selected for riparian zones, while raccoons selected for both riparian zones and rocky ridges, neither of which were selected for by nesting quail. Bobcats and male raccoons additionally showed a propensity for road travel, which quail often nested close to. Coyotes selected strongly for grasslands, utilized their home ranges comprehensively and showed a preference for road usage, and thus had the greatest potential encounter rate with quail nest sites. However, coyotes also showed the most linear and direct movement pattern, potentially reducing their efficiency in finding quail nests. This study indicates that coyotes potentially present the largest threat to the nests of quail and female raccoons the least. Management decisions such as the levels of management needed for the 3 species of mesopredators are discussed.
125

Nest site selection by the red-shouldered hawk (Buteo lineatus) in southwestern Québec

Morris, Michael Murray Joseph. January 1980 (has links)
No description available.
126

Habitat selection by sympatric black ducks and mallards in Abitibi, Quebec

Carrière, Suzanne January 1991 (has links)
Habitat use by sympatric black ducks (Anas rubripes) and mallards (A platyrhynchos) was studied in Abitibi, Quebec during May-August 1988 and 1989. / Black duck broods preferred emergent and shrub-rich areas in both years. Mallard broods' habitat use differed from 1988 to 1989 (from emergent to shrub-emergent areas) when average water levels were higher. Diversity of habitats seems more important to rearing black ducks than to mallards. Rearing mallards seem to modify their use of habitats according to changing habitat availability. Daily survival rates differed only slightly between "species". / Telemetry was used to study wetland use by six mallard and three black duck non-breeding females. Swamps were preferred whereas ericaceous shrub wetlands were avoided by both "species". Beaver (Castor canadensis) ponds were extensively used during the moulting period. Home ranges averaged 302.7 ha for black ducks and 201.2 ha for mallards.
127

Movement patterns, home range and habitat selection by Kakapo (Strigops habroptilus, Gray 1845) following translocation to Pearl Island, southern New Zealand

Joyce, Leigh, n/a January 2009 (has links)
Understanding the relationship between organisms and their environment is particularly important for the conservation and management of endangered species. The kakapo (Strigops habroptilus, Gray 1845) is a critically endangered, lek breeding, flightless nocturnal parrot endemic to New Zealand. In April 1998, a total population of fifty-six kakapo was known to survive on offshore islands. Twenty-six kakapo, thirteen males and thirteen females, were temporarily transferred to Pearl Island (518 ha), southern Stewart Island, from April 1998 to April 1999. The translocation of kakapo to Pearl Island, and subsequent breeding season, provided an ideal experimental framework to study kakapo dispersal, movement patterns, home range development, habitat selection, and lek development during the non-breeding and breeding seasons. A total of 4425 radio locations were analysed for all twenty-six birds, with a mean error polygon of 0.03 ha and an estimated average radio telemetry error of 21.6 m. Various home range analysis techniques were used to estimate kakapo home range size and overlap including: minimum convex polygons (MCP), modified minimum convex polygons (MMCP), harmonic mean analysis, adaptive kernel methods and cluster analysis. Estimates of kakapo home range size differed significantly depending on the method used (ANOVA, general linear model: F₁₃, ₁₀₇₆ = 63.99, p < 0.0001) and the season (F₂, ₁₀₇₆ = 160.75, p < 0.0001). Breeding home range size was significantly larger than non-breeding range size (mean difference = 67.6 ha, t₂₅ = 15.27, p < 0.0001). Calculations from 100% MCP and 95% harmonic mean analysis resulted in larger estimates of home range size and overlap compared to other methods. Cluster and kernel analyses appeared to give the most accurate home range representation for kakapo. Core home range areas showed a greater degree of similarity between methods. Male and female mean annual home range size did not differ significantly, whereas males had significantly (p < 0.05) larger home ranges than females during the nonbreeding season. Minimum convex polygons and harmonic mean analysis suggested that there was no significant difference in the way in which males and females interacted with each other. Kernel and cluster analyses indicated that females would overlap a greater proportion of another bird�s home range than males would. Cluster analysis also indicated that a female would have more of her home range occupied by another bird than a male would. The fact that different methods produced different quantitative results is an important consideration when using home range analysis to make conservation management decisions. Researchers must determine which method is the most appropriate for a particular research objective, species, or study area. The application of geographical information systems, ERDAS image classification techniques and global positioning systems was an integral part of this study. A large-scale vegetation classification map of Pearl Island was produced in order to quantify habitat selection by kakapo. The unsupervised classification technique produced the least accurate vegetation map, with an accuracy measure of 17-23%, compared to 52% for the supervised classification. The highest accuracy was obtained using an integrated approach involving inductive classification and deductive mapping, resulting in a vegetation classification map which correctly classified 95% of vegetation samples. Thirty-seven ecotone classes were identified and a total ecotone length of approximately 124 km was detected. Resource selection ratios and resource selection functions were estimated using a combination of discrete, continuous and area-based habitat variables. Circular buffers around used and available point locations were generated to determine whether kakapo selectively use vegetation mosaics. The probability of selection increased with increasing species diversity in each 75-metre radius buffer. Kakapo selected habitat mosaics and vegetation types with higher species diversity and moderate to high abundance of mature rimu and yellow silver pine trees.
128

Plant species habitat reversals in the upper South-East of South Australia /

Sparrow, Ashley. January 1984 (has links) (PDF)
Thesis (B. Sc. Hons)--University of Adelaide, 1984. / Includes bibliographical references (leaves 54-57).
129

Linking greater sage-grouse habitat use and suitability across spatiotemporal scales in central Oregon /

Freese, Mark T. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 107-115). Also available on the World Wide Web.
130

Transferability of models to predict selection of cover by coastal cutthroat trout in small streams in western Oregon, USA /

Andersen, Heidi V. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 47-55). Also available on the World Wide Web.

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