Nicrophorus americanus is a federally endangered species whose range has decreased dramatically since the 1920s. It is a nocturnal species that is only active from May to September when temperatures reach at least 15.5°C for three nights in a row. It once ranged throughout North America, from Maine and the southern parts of Canada, west to South Dakota and south to Texas. The historic Texas population consists of four Texas specimens from the 1880s residing at the Philadelphia Academy of Science Invertebrate Collection. Since then, there were no confirmed specimens in Texas, until 2003 when a single individual was found in Lamar County, Texas. The population discovered in Lamar County has been on a steady decrease from 2005, 223 individuals captured, until 2008 only 8 individuals captured. Since 2008, no individuals have been captured in Texas, despite intense surveys. It is possible that the Texas population is a sink population with the Oklahoma population to its north, acting as the source. Genetic analysis of the Texas and Oklahoma populations would help to answer this question and analysis of the entire population may answer questions to why the species declined leaving only the peripheral populations. The specific habitat variables that caused the population to re-colonize and go extinct in Texas are unclear, but when determined could play a critical role in managing the population. / text

No description available.

Research can conflict with conservation when invasive techniques are used on protected animal species. We developed a decision framework including the research question, the choice of technique, and the recommended course of action following the evaluation of the risks and benefits. This evaluation includes biological risks and benefits and considerations linked to the perception of resource users. We applied this framework a posteriori to a case study, the use of biopsy sampling on St. Lawrence belugas. We monitored the biological risks and benefits over four field seasons using behavioural and physiological indices and reports on the work in progress. We evaluated the risks as "low" and the benefits as "medium". For benefits to outweigh risks, procedures to minimise risks, publication of the work, and formulation of recommendations for conservation are essential. Researchers should be prepared to discuss with stakeholders the potential conflicts between their projects and conservation.

There is no abstract available for this thesis. / Department of Biology

Earlier studies have found that endangered species recovery is only weakly associated with the tools enabled by the U.S. Endangered Species Act (ESA). With habitat loss often cited as a leading cause of species declines, we tested whether the recovery of ESA-listed species is instead associated with the protection of critical habitat (CH) by protected areas. We tested the relationship for 299 species using recovery indices derived from the biennial status reports to Congress (1990-2010), as well as NatureServe and IUCN population status data. We found no overall relationship between recovery and the extent to which CH is protected. However, restricting the analysis to recovering species, listed species with larger areas of protected (R2 = 0.158) or strictly protected (R2 = 0.194) CH fared better than species with less protected or strictly protected CH areas. Declining species (199 of 273 species studied) fared no better with more protected habitat. We conclude that the abatement of habitat loss alone does not necessarily facilitate recoveries for the majority of ESA-listed species. We also note that the weak relationships we observed in this study may be reflective of poor recovery status estimates.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references. / Also available by subscription via World Wide Web / ix, 202 leaves, bound ill., map 29 cm

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.

Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen (viewed 1/24/2008). "MES thesis." Includes bibliographical references (p. 79-88).

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 6 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.