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Ecological determinants of muntjac deer Muntiacus reevesi behaviourKeeling, Jonathan Giles Matthew January 1995 (has links)
No description available.
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Geographic Range Size: Measuring The Fundamental Unit Of Biogeography and Evaluating Climatic Factors That May Influence Longitudinal Range Size Gradients In North American TreesDonoghue, John, Donoghue, John January 2016 (has links)
This research seeks to advance our understanding of how to make better informed species conservation decisions on a global scale and advance our understanding of how species' spatial distributions (their geographic ranges) may be respond to climate change, so we can know which areas should be set aside to ensure their present and future conservation. To understand how species' geographic ranges may change, it's important to first assess how geographic ranges are defined and measured. The quantifiable measurement of a species' geographic range, (its geographic range size), is a key criterion the International Union for the Conservation of Nature uses to determine the conservation status and prioritization of species worldwide. Thus, part one of this thesis evaluates different measures for how geographic range size is commonly quantified in the conservation community, to determine whether some range size measures are more reliable than others.Further, to evaluate how species' geographic ranges may respond to climate change, I examine the climatic factors influencing observable longitudinal range size gradients in the North American tree species range maps from E.L. Little's Atlas of North American Trees.
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Behavioural ecology of Przewalski horses (Equus przewalskii) reintroduced to Hustai National Park, MongoliaKing, Sarah Rachel Buckley January 2012 (has links)
Studies on the behavioural ecology of Przewalski horses (Equus przewalskiiy) recently reintroduced into Hustai National Park, Mongolia were carried out between 1998 and 2000. Home range size and habitat use, social, marking, and vigilance behaviour, and their reaction to flies were quantified. Home ranges of harems ranged from 129 ha to 2399 ha, with core areas of between 61 ha and 1196 ha. There was no relationship between range size and harem size, or length of time since release. The more nutritious vegetation at lower elevations was preferentially selected. The horses rested near ridges during the hotter parts of the day where there were fewer flies, and grazed in the valleys in the mornings and evenings. Woodland areas were used to shelter from the sun, despite their high fly abundance. Muscid flies were most frequently caught; Tabanids were rare. Dominance was related to age, aggression and length of time in the harem. The frequency of associative behaviours did not correlate with any social factor, but had a hygienic function. Stallions marked stud piles wid mare eliminations in different ways suggesting different functions. In addition to being vigilant for predators, the horses appeared to scan for social cues and food patches. Home range size and habitat use, and general pattern of marking and vigilance behaviour, of the wild Przewalski horses were similar to those seen among feral domestic horses, although they tended to be less aggressive than captive and feral horses. So far, the re-establishment of przewalski horses into HNP appears to have been successful, although constant monitoring of the population is necessary. As the population grows, there will be potential problems to do with exceeding the carrying capacity of the park and hybridisation with domestic horses. The future management of the horses is discussed.
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Can Landscape Composition Predict Movement Patterns and Site Occupancy by Blanding's Turtles?: A Multiple Scale Study in Québec, CanadaFortin, Gabrielle 07 December 2012 (has links)
As habitat loss and fragmentation are major causes of decline in animal species, studying habitat requirements in these species is a key component of their recovery. I investigated the relationship between landscape composition and habitat use of Blanding’s turtles, Emydoidea blandingii, a freshwater turtle threatened by habitat loss and road mortality on most of its Canadian range. In 2010, I conducted a radio-telemetry survey of 44 Blanding’s turtles in southern Québec, Canada, and modelled their home range size from land cover proportions measured at many spatial scales. I also used data from a visual survey conducted in 2008 and 2009 to model wetland occupancy of the species at the landscape scale. Home range size of the Blanding’s turtle was significantly correlated to landscape composition, and the proportions of agriculture, open water and anthropogenic lands had the strongest relationships with home range size. However, those relationships were weak and the models were unable to predict home range size accurately. At the landscape scale, land cover and road density poorly predicted probability of occurrence, and Blanding’s turtles occupied wetlands in both disturbed and natural sites. Management of the species should focus on protecting sites of occurrence with high wetland density, low road density, and sufficient suitable habitat to cover their seasonal movement patterns.
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Mechanisms for Range Size and Distribution Variation in the Polyploid Complex Black-fruited Hawthorn (Crataegus series Douglasianae): Biogeographic Implications for the Maintenance of Cytotype DiversityCoughlan, Jennifer 21 November 2012 (has links)
Polyploidization is exceptionally cosmopolitan in plants. One common observation is that polyploids inhabit larger geographic distributions than their diploid progenitors. Differences in distribution between cytotypes are largely attributed to differences in mating system and ecological breadth among cytotypes. In Crataegus series Douglasianae, allopolyploids have larger ranges than their diploid progenitors. Range size increase is coupled with a shift to predominant asexuality in polyploids. This thesis explores 2 additional hypotheses that may contribute to differences in distribution among cytotypes: ecological breadth and dispersal ability. We find evidence that tetraploid C. douglasii occurs in a wider range of habits and has a greater dispersal ability than diploid C. suksdorfii. Overall, we suggest that differences in mating system, ecological breadth, and dispersal ability have contributed individually and collaboratively to differences in distribution among cytotypes of Crataegus series Douglasianae. Large ranges in polyploids may help maintain cytotype diversity by providing buffering capacity against demographic stochasticity.
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Mechanisms for Range Size and Distribution Variation in the Polyploid Complex Black-fruited Hawthorn (Crataegus series Douglasianae): Biogeographic Implications for the Maintenance of Cytotype DiversityCoughlan, Jennifer 21 November 2012 (has links)
Polyploidization is exceptionally cosmopolitan in plants. One common observation is that polyploids inhabit larger geographic distributions than their diploid progenitors. Differences in distribution between cytotypes are largely attributed to differences in mating system and ecological breadth among cytotypes. In Crataegus series Douglasianae, allopolyploids have larger ranges than their diploid progenitors. Range size increase is coupled with a shift to predominant asexuality in polyploids. This thesis explores 2 additional hypotheses that may contribute to differences in distribution among cytotypes: ecological breadth and dispersal ability. We find evidence that tetraploid C. douglasii occurs in a wider range of habits and has a greater dispersal ability than diploid C. suksdorfii. Overall, we suggest that differences in mating system, ecological breadth, and dispersal ability have contributed individually and collaboratively to differences in distribution among cytotypes of Crataegus series Douglasianae. Large ranges in polyploids may help maintain cytotype diversity by providing buffering capacity against demographic stochasticity.
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Determination Of Home Range Size And Habitat Selection Of Gazelles (gazella Subgutturosa) By Gps Telemetry In SanliurfaDurmus, Mustafa 01 February 2011 (has links) (PDF)
Goitered gazelle is one of the threatened species of Turkey living in only & / #289 / anliurfa region. In this study, goitered gazelles have been released to their previous habitat in Sanliurfa-Suruç / region and seven of females were collared with GPS collars. These individuals were monitored for a year and their seasonal habitat selection and home range sizes are determined by using location data recorded on the collars. In addition to 4 seasons of the year, home range and habitat selection are estimated for mating and calving periods. Also, summer period is divided to two as summer1 and summer 2 because of changing availability of water resources in study area. Seasonal home range sizes of GPS collared gazelles are estimated as average 3.61 ± / 0.47 km2 for winter, 3.96 ± / 0.44 km2 for spring, 4.55 ± / 1.35 km2 for summer1, 2.26 ± / 0.20 km2 for summer2, 3.38 ± / 0.44 km2 for autumn, 1.37 ± / 0.50 km2 for mating season, and 1.66 ± / 0.50 km2 for calving season.Seven habitat variable layers were prepared for the evaluation of seasonal habitat selection of GPS collared female gazelles. Gazelles were selected east aspects in summer and west aspects in winter seasons and, north and flat aspects were avoided in all seasons for a year. Water can be considered the key habitat variable for the goitered gazelles. The results show that some home ranges are outside of the protected area and gazelles do not use large areas in the protected area. In order to improve conservation of gazelles, protected area should be re-arranged and shifted to more intensely used areas by gazelles.
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Sex differences in spatial memory ability: a test of the range size hypothesis in the order carnivoraPerdue, Bonnie Marie 23 March 2011 (has links)
Sex differences in spatial cognition have been reported for many species ranging from voles to humans. The range size hypothesis predicts that sex differences in spatial ability will only occur in species in which the mating system selects for differential range size. Consistent with this prediction, we observed sex differences in spatial ability in giant pandas, a promiscuous species in which males inhabit larger ranges than females, but did not observe sex differences in Asian small-clawed otters, a related monogamous species in which males and females share home ranges. Furthermore, the sex difference in giant pandas was observed during the period of male range expansion and outside female estrus, thus the potentially confounding influence of decreased female ability was avoided. Finally, all subjects in this study were raised in captivity and never actually inhabited different range sizes. Therefore these findings emphasize the importance of biological rather than experiential factors underlying sex differences in spatial cognition. These results are the first evidence of sex differences in spatial ability in the order Carnivora, and provide support for the range size hypothesis.
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Can Landscape Composition Predict Movement Patterns and Site Occupancy by Blanding's Turtles?: A Multiple Scale Study in Québec, CanadaFortin, Gabrielle 07 December 2012 (has links)
As habitat loss and fragmentation are major causes of decline in animal species, studying habitat requirements in these species is a key component of their recovery. I investigated the relationship between landscape composition and habitat use of Blanding’s turtles, Emydoidea blandingii, a freshwater turtle threatened by habitat loss and road mortality on most of its Canadian range. In 2010, I conducted a radio-telemetry survey of 44 Blanding’s turtles in southern Québec, Canada, and modelled their home range size from land cover proportions measured at many spatial scales. I also used data from a visual survey conducted in 2008 and 2009 to model wetland occupancy of the species at the landscape scale. Home range size of the Blanding’s turtle was significantly correlated to landscape composition, and the proportions of agriculture, open water and anthropogenic lands had the strongest relationships with home range size. However, those relationships were weak and the models were unable to predict home range size accurately. At the landscape scale, land cover and road density poorly predicted probability of occurrence, and Blanding’s turtles occupied wetlands in both disturbed and natural sites. Management of the species should focus on protecting sites of occurrence with high wetland density, low road density, and sufficient suitable habitat to cover their seasonal movement patterns.
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Can Landscape Composition Predict Movement Patterns and Site Occupancy by Blanding's Turtles?: A Multiple Scale Study in Québec, CanadaFortin, Gabrielle January 2012 (has links)
As habitat loss and fragmentation are major causes of decline in animal species, studying habitat requirements in these species is a key component of their recovery. I investigated the relationship between landscape composition and habitat use of Blanding’s turtles, Emydoidea blandingii, a freshwater turtle threatened by habitat loss and road mortality on most of its Canadian range. In 2010, I conducted a radio-telemetry survey of 44 Blanding’s turtles in southern Québec, Canada, and modelled their home range size from land cover proportions measured at many spatial scales. I also used data from a visual survey conducted in 2008 and 2009 to model wetland occupancy of the species at the landscape scale. Home range size of the Blanding’s turtle was significantly correlated to landscape composition, and the proportions of agriculture, open water and anthropogenic lands had the strongest relationships with home range size. However, those relationships were weak and the models were unable to predict home range size accurately. At the landscape scale, land cover and road density poorly predicted probability of occurrence, and Blanding’s turtles occupied wetlands in both disturbed and natural sites. Management of the species should focus on protecting sites of occurrence with high wetland density, low road density, and sufficient suitable habitat to cover their seasonal movement patterns.
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