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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.
61

Seasonal movement and activity patterns of the endangered geometric tortoise, Psammobates geometricus.

Van Bloemestein, Ulric Patrick January 2005 (has links)
Due to the critical status of Psammobates geometricus and the vulnerability of their habitat, there is a need to allocate areas for their protection. The aim of this study was to provide information on the space requirements and activity level of geometric tortoises to facilitate future conservation efforts.
62

The Big Bad EU? Species Protection and European Federalism : A Case Study of Wolf Conservation and Contestation in Sweden

Epstein, Yaffa January 2017 (has links)
This dissertation examines how eco-knowledge intersects with the changes to EU legal cultures and practices known as eurolegalism. This conjunction has created a mechanism for the extension of EU law in the Member States even in the face of a weakened EU. Through a portfolio of six articles, controversies over the protection of wolves in Sweden are used to illustrate and explicate the changing roles and responsibilities of various actors in protecting species, and the centralization of competence for environmental protection in Europe at the EU level. In doing so, some substantive requirements of the Habitats Directive are also analyzed. The first article maps the movement of competence to determine conservation policy towards the EU level and away from international and Member State actors. The second article examines what the EU requires of its Member States by analyzing the Habitats Directive’s key concept, favourable conservation status. It also makes normative arguments for how contested aspects of this concept should be interpreted to best achieve the Directive’s conservation goals. The third article deepens this analysis by applying these arguments to the Swedish wolf population. The fourth article is a case commentary illustrating the enforcement of the Habitats Directive through public interest litigation to stop the hunting of Swedish wolves. The fifth argues that the greater availability of public interest standing in the US than in the EU has led to the greater implementation of federal law. The sixth argues that greater availability of public interest litigation in Sweden than previously is also leading to the greater enforcement of “federal” EU law. Each of these articles demonstrates or explains factors that lead to the hollowing out of state power in favor of the EU and interest groups. / <p>Cover photo by Guillaume Chapron</p>
63

The fox, the fence and the flux : human-animal relations and environmental knowledge in rural and protected areas in south-central Chile

Benavides Medina, Sebastián Pelayo January 2017 (has links)
This thesis focuses on the relationship of various actors with wild animals, specifically wild predators protected by law, in rural and protected areas of south-central Chile (IX Araucanía Region). It is based on a 12 month period of ethnographic fieldwork, distributed in the Huerquehue National Park, a private protected area ('Cañi Sanctuary') and a small farm close to the Villarrica National Park. Participant observation was developed with park rangers, conservation researchers and small-scale farmers. Most of these were also interviewed through in-depth, semi structured approaches, as other key informants, mainly neighbouring local farmers and government officials. My aim is to understand anthropologically how humans and animals interact, considering various contexts, and contributing to Chilean academia in better understanding the situation of endangered species in the country. The main theoretical points I argue are that human-animal relations are inscribed in a broader environmental approach, regarding classifications about the natural world, humanity's place in it, and their separation. Thus, the study analyses participants' environmental engagements and their relations with wild protected predators and other animals, showing how practical engagements help to 'piece together' the surroundings and other creatures. Considering uncertainty and fuzzy boundaries regarding implied classifications and fleeting experiences with animals, the analysis then focuses on the interpretation of animal tracks and traces and tracking, as flexible and open ended engagements with the environment and its clues, connected to the semiotic concept of 'abduction'. Finally, I return to reflections concerning a fluctuating world, crossed by uncertainties and categories' limitations. Using the concept of 'the uncanny', I explore alternative interpretations of relations with animals and the environment, connected with strangeness and unpredictability, where regular knowledge and ontological assumptions are challenged. I finish by stressing the fertility of being open to complex knowledge, related with a fluctuating and uncanny world that resists well-defined categorisations.
64

Assisted reproduction and subsequent embryo development to form embryos for transfer and cryobanking in endangered cats using the domestic cat as a model

Pushett, David, 1968- January 2000 (has links)
Abstract not available
65

Conservastion biology of the pink-tailedd legless lizard Aprasia parapulchella

Jones, Sandra Raelene, n/a January 1999 (has links)
This study arose from a conservation dilemma between the need to conserve a population of the endangered pink tailed legless lizard, Aprasia parapulchella and crucial upgrading of Canberra's sewerage treatment plant. The study focused on conservation biology and how it could be applied to the management of A. parapulchella. As little biological information was available on A. parapulchella, research was focused on obtaining data that would be beneficial in the conservation management of the species. This included the dietary and habitat requirements, population status and structure and population relocation and habitat restoration. A. parapulchella was found to occur in low relative densities at all sites (maximum 9.1 lizards per 1000 rocks turned, Mt Taylor). Populations of the species appear to be larger than has been considered previously, however numbers are still below 500 individuals per site. Sexual dimorphism is present in the species with females achieving longer snout-vent lengths than males. Sex ratios were equal in all sites, however average size of lizards was different at the four main study sites, indicating differences in population structure. The life history of A. parapulchella can be summarised as long-lived, late maturing (3rd or 4lh year of life) with a low reproductive rate (single clutch of two eggs per year). A. parapulchella is a dietary specialist feeding on about 11 different species of ants. Interestingly, the lizards also live with the same species that they feed upon. By far the most important species in the diet and homesite requirements of A. parapulchella is the ant Iridomyrmex rufoniger. A. parapulchella shows positive selection towards the species in homesite choice, is found most commonly in the nests of this ant, and selects its brood over the brood of other ant species in diet experiments. In addition this ant was represented in the diet of A. parapulchella more commonly than any other ant. The relationship between ants and A. parapulchella appears to be unique and the mechanisms of this specialisation require further investigation. The vegetation associations where A. parapulchella occur are different across the range of the species. Sites at Bendigo and West Wyalong support mallee communities, while in the ACT region, Bathurst and Tarcutta, A. parapulchella appears to be a habitat specialist, being found most commonly in sites dominated by grass species, both native and introduced. A. parapulchella lives beneath rocks in grassland sites. Rocks that the species uses for homesites are commonly between 100 and 150 mm wide, 120-220 mm long and 50 and 150 mm thick. There were significant differences between the sizes of rocks used at different sites and between different seasons. Rocks used by females were significantly larger than rocks used by juvenile lizards. Twelve other species of reptile were found to use rocks in grassland sites, with rocks partitioned within the community on the basis of size and shape. An experimental relocation of A. parapulchella was conducted to try to determine ideal habitat conditions for the survival of relocated individuals. Unfortunately of the 114 lizards released, only 15 were recaptured. Although recaptures were low, trends indicated that treatments of Themeda triandra and very high rock densities had the highest survival rates. Key habitat variables were reinstated at the Lower Molonglo Dam site however restoration is preliminary with more time needed for the habitat to be suitable for occupation by A. parapulchella. What started as a situation that was likely to have a deleterious impact on A. parapulchella has been turned into a conservation success story. Without the involvement of ACT Electricity and Water, much of the basic biology of A. parapulchella would still be unknown. The findings will now form a solid basis from which to effectively conserve A. parapulchella. The project provides an example of the conservation success that can be achieved between industry and conservation partnerships.
66

Habitat requirements and habitat use of the red-crowned toadlet Pseudophryne Australis and the giant burrowing frog Heleioporus Australiacus in the Sydney basin.

Stauber, Andrew G. January 2006 (has links)
Habitat requirements and habitat use for Pseudophryne australis and Heleioporus australiacus were investigated to aid management of these threatened frogs around Sydney, Australia. Much of the work focussed on roads, commonly encountered features in the habitat of both species. The habitat requirements based on locality records of both frogs in the Sydney Basin were investigated at four spatial scales. Both species are habitat specialists. They showed a strong geological association with Hawkesbury Sandstone and occupy upper topographic areas with ephemeral watercourses of gentle gradients. Both frogs occur predominantly in areas of higher precipitation and milder temperature regimes compared to averages representative of the region. Leaf litter is an important feature of P. australis breeding sites, whereas H australiacus generally associate with crayfish burrows. Both species are dependent on natural vegetation with a complex structure. H australiacus have a relatively long larval period (3 - 12 months) and breed in ephemeral pools, exposing their tadpoles to the risk of dying due to early pond drying. In the laboratory, tadpoles responded to decreasing water levels by shortening their larval periods and metamorphosing earlier than siblings held at constant water level. Despite this plastic response, a number of pools in the field failed to produce metamorphs due to early drying, an observation also made on P. australis. Regular monitoring of breeding sites revealed increased reproductive success away from roads for both species probably because of relatively longer hydroperiods. Spatial distributions and associations with habitat features, and movement patterns of both frogs were further investigated using mark-recapture methods. Both species showed strong site fidelity. P. australis formed small aggregations and predominantly selected leaf litter piles despite their relatively low availability. Leaf litter piles in creeks moved over time and the animals moved with these piles. In contrast, H australiacus individuals formed no aggregations and showed no preference for any available structural vegetation type. Locations of individuals were independent of relative distances to creeks and artificial drains, but males appeared to be more common near culverts. However, individuals were randomly distributed in space and nearest-neighbour distances were high relative to individual movement distances, suggesting minimal overlap between relatively large home ranges. Radio-telemetry demonstrated that some H australiacus individuals burrow in the road environment. There they would be at risk of being dug up and possibly injured during road works. The results are discussed in relation to the spatial requirements of both species and the protection of utilised habitat features. Management options are suggested to mitigate the impacts of road works. Differences in spatial dynamics of both frogs with overlapping habitats highlighted in this study require species-specific management approaches.
67

Habitat requirements and habitat use of the red-crowned toadlet Pseudophryne Australis and the giant burrowing frog Heleioporus Australiacus in the Sydney basin.

Stauber, Andrew G. January 2006 (has links)
Habitat requirements and habitat use for Pseudophryne australis and Heleioporus australiacus were investigated to aid management of these threatened frogs around Sydney, Australia. Much of the work focussed on roads, commonly encountered features in the habitat of both species. The habitat requirements based on locality records of both frogs in the Sydney Basin were investigated at four spatial scales. Both species are habitat specialists. They showed a strong geological association with Hawkesbury Sandstone and occupy upper topographic areas with ephemeral watercourses of gentle gradients. Both frogs occur predominantly in areas of higher precipitation and milder temperature regimes compared to averages representative of the region. Leaf litter is an important feature of P. australis breeding sites, whereas H australiacus generally associate with crayfish burrows. Both species are dependent on natural vegetation with a complex structure. H australiacus have a relatively long larval period (3 - 12 months) and breed in ephemeral pools, exposing their tadpoles to the risk of dying due to early pond drying. In the laboratory, tadpoles responded to decreasing water levels by shortening their larval periods and metamorphosing earlier than siblings held at constant water level. Despite this plastic response, a number of pools in the field failed to produce metamorphs due to early drying, an observation also made on P. australis. Regular monitoring of breeding sites revealed increased reproductive success away from roads for both species probably because of relatively longer hydroperiods. Spatial distributions and associations with habitat features, and movement patterns of both frogs were further investigated using mark-recapture methods. Both species showed strong site fidelity. P. australis formed small aggregations and predominantly selected leaf litter piles despite their relatively low availability. Leaf litter piles in creeks moved over time and the animals moved with these piles. In contrast, H australiacus individuals formed no aggregations and showed no preference for any available structural vegetation type. Locations of individuals were independent of relative distances to creeks and artificial drains, but males appeared to be more common near culverts. However, individuals were randomly distributed in space and nearest-neighbour distances were high relative to individual movement distances, suggesting minimal overlap between relatively large home ranges. Radio-telemetry demonstrated that some H australiacus individuals burrow in the road environment. There they would be at risk of being dug up and possibly injured during road works. The results are discussed in relation to the spatial requirements of both species and the protection of utilised habitat features. Management options are suggested to mitigate the impacts of road works. Differences in spatial dynamics of both frogs with overlapping habitats highlighted in this study require species-specific management approaches.
68

Endangered bird species in South Australia : are current recovery practices for the Orange-bellied parrot and Kangaroo Island glossy black cockatoo succeeding?

Klövekorn, Henning Andreas. January 1998 (has links) (PDF)
Bibliography: leaves 108-113. This dissertation givens and analytical overview of the research and recovery actions for the Orange-bellied Parrot and the Kangaroo Island Glossy Black-Cockatoo and evaluates the successful practices and those which have failed. This research shows that new recovery action initiatives can still be found and that not all recommendations in recovery plans are followed, which impairs the efficiency of the recovery efforts. It concludes that a successful recovery effort of these two bird species lies in continued research, a serious compliance with the recommendations made by recovery plans and by further environmental education in society.
69

Binational collaboration in recovery of endangered species: the Mexican wolf as a case study

Bernal Stoopen, Jose Francisco 30 September 2004 (has links)
The goal of this inductive study was to identify factors that facilitate and inhibit binational collaboration in the recovery of endangered species in the northern Mexico borderlands, focusing on the Mexican wolf (Canis lupus baileyi). A conceptual model was developed using qualitative techniques, providing the basis for design of a mail survey. The target population included participants with experience in recovery efforts for over a dozen species at risk in the region. Long interviews were recorded with 44 participants from Mexico and the United States. Thematic hierarchical analysis was used to develop a conceptual model of how interviewees talked about factors influencing binational collaboration. Issues were classified in five thematic clusters: project, organization, people, resources, culture/history. The survey was used to conduct a needs assessment, measuring respondents' attitudes about the relative priority of issues identified in the conceptual model. High priority needs were identified from each thematic cluster: (a) equitable participation in project design and implementation, (b) continuity of personnel, (c) coordination of federal, state and local efforts, (d) increased funding, managed with accountability, and (e) exchange visits to facilitate understanding of diverse perspectives. Responses to almost half the survey items indicated accord among the sample of respondents, providing a basis for shared common ground. The nature of discord was within the range of "manageable", with no clear polarization of attitudes measured. This exploratory data analysis suggested that the structure of the conceptual model developed from the Mexican wolf case study was generally a valid basis for future deductive analysis and reflection by practitioners. For 82% of 22 statements of need, priorities of participants in the Mexican wolf recovery efforts did not differ significantly from other respondents. Nationality (of respondents) significantly affected priority rankings for only 18% of the need statements. Significant effects of five demographic variables indicated that interactive effects should be examined in future multivariate analyses to determine how respondents' attitudes on issues related to priority rankings. Recommendations were provided for a more efficient and effective approach to collaborative problem-solving, engaging reflective practitioners from the private and public sectors in principled negotiation processes to better understand diverse perspectives.
70

Modeling aspects of the ecological and evolutionary dynamics of the endangered Houston toad

Swannack, Todd Michael 15 May 2009 (has links)
The goal of my dissertation was to describe the dynamics of a group of Houston toads located at the Griffith League Ranch (GLR), Bastrop County, Texas. My research included using statistical modeling to predict activity and abundance, mark-recapture techniques to estimate survivorship, and simulation modeling to explore the impacts of the difference in age at first reproduction and to project the future dynamics of the population at the GLR. From 2001 – 2005, 225 individual Houston toads (199 M : 26 F) were captured using two methods: breeding pond surveys and drift fences. Houston toads were neither caught equally among capture methods, nor across years. Toad activity was mostly confined within their breeding season, and activity was not continuous. A logistic regression indicated activity depended on time of year, mean precipitation, mean minimum daily temperature, and mean percent lunation as well as two-way interactions with moon-phase and other variables. Abundance depended on time of year, current precipitation, minimum temperature, and two-way interactions between time of year and the other two variables. Twenty-one of the 199 males (10.5%) and no females were recaptured among years. The probability of male survival was estimated using program MARK. Eight of 16 candidate models were supported and all but one contained precipitation as a covariate, indicating precipitation is important for Houston toad survival. Survivorship estimates varied from 0.1 to 0.41. The sex ratio was significantly male-biased. The odds of catching females in traps were 3.5 greater than capturing females in a pond, while the odds of capturing males in a trap were 0.28 compared to ponds. Results from a simulation model indicated the sex ratio is biased because of the difference in maturation times between males and females, coupled with high juvenile mortality. Results from an individual-based, spatially-explicit, stochastic simulation model, indicated a relatively low probability (~ 0.013) of B. houstonensis going extinct at the GLR within the next 10 years. Emergent properties of the model were similar to results observed in the field or reported in the literature. The model also identified that dispersal of Houston toads should be a future research priority.

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