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Master of Science / Department of Clinical Sciences / James W. Carpenter / In many species, temporary increases in glucocorticoids (GC) can be used to identify changes in adrenal activity in response to acute stressors. For this research, GC metabolites were identified in fecal extracts from various Atelopus species. The objectives were to identify possible correlates between GCs and health status, assess the impact of husbandry protocols on adrenal activity, and evaluate the sub-lethal effects of antifungal bacteria used for protection of frogs against the chytrid fungus (Batrachochytrium dendrobatidis; Bd). The first study examined whether fecal GC concentrations can be correlated with animal health and behavior changes in a captive setting. Atelopus zeteki with varying degrees of dermatitis were categorized based on the severity of their skin abnormalities and GC metabolite concentrations were analyzed to detect correlations between severity of disease and GC metabolite concentrations. Similarly, behaviors that may indicate elevated stress levels (e.g., time spent in hide) were analyzed to detect correlation between disease and behavior changes. There was no correlation between fecal GC metabolites and health status of the animal or between health status and amount of time spent in hide. The second study established ex situ colonies of two Panamanian frog species, Atelopus certus and Atelopus glyphus, to determine how male group size affects behavior and GC levels. When housed in groups of eight, animals initially had elevated GC concentrations and interacted aggressively, but these instances declined substantially in the first 2 weeks of being housed together. Thus, captive Atelopus populations can be housed in same-sex enclosures without causing sub-lethal stress on the individuals involved. The third study examined the ability of antifungal bacterium from Central America to propagate on Atelopus skin as a preventative treatment for Bd and the sub-lethal effects of each bacteria species on adrenal function based on GC analysis. Four species of bacteria (Pseudomonas sp., Pseudomonas putida, Chryseobacterium indolgenes, and Stenotrophomonas maltophili) were found to be successful Bd inhibitors in vitro. There were no detectable effects of bacterial exposure with GC metabolite concentrations over time for any of the treatments assessed.

Thesis (PhD (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / The Okavango Delta, Botswana, is a unique ecosystem and this is reflected in its extraordinary biodiversity. The Nile crocodile (Crocodylus niloticus Laurenti) is the apex predator, and performs a number of vital functions in this system, making it a keystone species. The panhandle crocodile population has declined significantly over the last 80 years and is now threatened as a result of past over-exploitation and present human disturbance. In order to effectively conserve this species and in turn the health of this important region it is imperative to gain an understanding of their ecology and population dynamics. The population status of the Nile crocodile in the panhandle region of the Okavango Delta, Botswana, was assessed using a combination of capture-mark-recapture surveys, spotlight surveys and aerial surveys. The capture-mark-recapture experiment was conducted continuously from 2002 - 2006. A total of 1717 individuals, ranging in size from 136 mm – 2780 mm SVL, were captured, of which 224 animals were recaptured. Using a Bayesian technique, the total annual population in the panhandle region of the Okavango Delta was estimated to be 2 570 ± 151.06 individuals, with an adult population of 649.2 individuals with the number of breeding females estimated to be 364 individuals. It was concluded that this population cannot sustain the further harvest of breeding animals prior to the increase and stabilization of the population. Spotlight counts revealed a decline in the encounter-rate of crocodiles on the Okavango River with time, although more long-term data needs to be collected to confirm this trend. During the low-water season (September - February), 22.34 % of all crocodiles were observed, while during the flood-season only 13.34 % were observed, yielding correction factors for spotlight surveys of 4.46 (low-water) and 7.49 (high-water) for all animals in the panhandle. Two aerial surveys, conducted at the low-water and high-water peaks yielded total estimates of 588 (77.7 % of adults) during the low-water period and 350 (56.7 % of adults) during the high-water period. Correction factors of 1.28 (low-water) and 1.77 (high-water) were calculated for aerial surveys. An annual average of 50 nests was located in the panhandle, representing a 50 - 60 % decrease over the last 20 years. In regions with high human disturbance, breeding females situated their nests in hidden locations, away from accessible channels. Hatchlings exhibited elongation of the jaw in order to capture smaller prey items and morphometric shifts in jaw shape coincided with a dietary change at 400 mm SVL. The jaw became broader and deeper as animals matured, presumably in preparation for larger mammalian prey. The average growth rate of recaptured yearlings was 0.198 ± 0.116 mm.d-1 SVL and was closely correlated to the amount of time an individual spent in above-average water temperatures. Body condition (RCF) was significantly and positively correlated with a rise in water-level and negatively correlated to time spent in above-average water and air temperatures. Average RCF values were intersected when animals had spent 50 % of their time in above-average temperatures and water level. Generally crocodiles in the panhandle showed no significant sex-related differences in their sizes or the distances they travelled. The majority of recaptures (62.5 %) moved less than 500 m from the initial capture site. Adults in the panhandle occupied definite ranges, within which were preferred core areas where the majority of their time was spent. The panhandle crocodile population has declined significantly over the last 80 years, and is now threatened as a result of past over-exploitation and present human disturbance. The management of this population, including both its conservation and sustainable commercial utilisation, requires an adaptive strategy based on accurate monitoring procedures.

Home range, habitat use, and movements of reintroduced masked bobwhite (Colinus virginianus ridgewayi) were studied during 1986-88 on the Buenos Aires National Wildlife Refuge in southern Arizona. Home ranges averaged 10.9 ha (5.2-14.6 ha), and core areas averaged 1.1 ha (0.2-2.7 ha). Core areas had significantly higher visual obstruction by vegetation from 0-1 dm, aerial and basal grass cover, and significantly lower bare ground, litter, half-shrub cover, half shrub density, and visual obstruction by vegetation from 5-20 dm than non-core areas. The majority of the masked bobwhite moved less than 1 km between their release location and the site of first trapping. However, some long distance movements occurred. Once home ranges were established, masked bobwhite seldom left the boundaries. Key habitat components are identified for masked bobwhite on the Buenos Aires National Wildlife Refuge.

The need to understand the dynamics of the impala population in Mkuzi Game Reserve arose during the early 1960's when it became clear that various factors were contributing to an overpopulation of the species in the reserve. Population management was recognized as being necessary and was carried out, but it was based on inadequate information. This study set out to establish a rational basis for future management. The social organization and behaviour of impala in Mkuzi were analysed and placed in perspective relative to the population dynamics. Two methods of counting the animals were used and a relationship obtained between the respective results. The distribution of impala within the reserve, both on a gross population basis and with respect to the various sex and age categories, was determined from sampling. In order to establish the age structure of the population, samples obtained from the control programme were used, and these were aged on the basis of molar wear. At the same time the proportions of young animals and the population sex ratios were obtained by field sampling. Using these data, life tables were constructed, from . which it was possible to interpret the behaviour of the population at the time of the study. However, caution should be exercised in extrapolating these results literally to the same population under different conditions. The study only provides guidelines for regular monitoring to be carried out. At the same time a more detailed study of the vegetation dynamics of Mkuzi Game Reserve is a priority so that the relationship between the animal and plant elements of the reserve can be properly analysed. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1979.

Road networks have significant impacts on ecosystems through deforestation, rapid land conversion and wildlife-vehicle collisions. Road ecology seeks to analyze the spatial and biological patterns of collisions to understand the effect of roadways and best inform transportation planning in mitigating these threats. 215 km of roadway BR-262, that bisects critical habitat of the Brazilian Cerrado and Pantanal in southwest Brazil, was analyzed between April 2011 and June 2012 to assess how biological, physical and landscape characteristics affect clustering of collisions. 518 collisions, representing 40 species, were found to be seasonally clustered between the unimodal rain and flood pulse in a February-March-April window and were spatially clustered over the study area in relation to cash crop and cattle ranching land-use and the rural low-lying Pantanal floodplain. Mitigation seeks to work with local communities and transportation agencies to facilitate fauna safe crossing through the roadway that do not conflict with drivers. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

This dissertation examined the natal origins, home-range, and in-situ foraging behavior of an aggregation of sub-adult hawksbill turtles (Eretmochelys imbricata) found off the coast of Palm Beach County, Florida. Surveys were conducted on approximately 30 linear km of reef between 15 and 30 m in depth. Tissue samples were retrieved from 112 turtles for mtDNA haplotype determination. GPS-linked satellite transmitters were deployed on six resident sub-adults, resulting in both minimum convex polygon (MCP) and 95%, 50%, and 25% kernel density estimates (KDE) of home-range size. A foraging ethogram was developed, and sequential analysis performed on thirty videos (141 total minutes) of in-situ foraging behavior. Seventeen total haplotypes were identified in this aggregation, the majority (75%) of which represented rookeries on Mexico’s Yucatan Peninsula. Other sources, from most to least important, include Barbados, Costa Rica, Puerto Rico, Antigua, and the U.S. Virgin Islands. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

The surveillance and control of introduced species has become an increasingly important, yet often controversial, form of environmental management. I investigate why and how introduced species management is initiated; whether, why and how it is contested; and what relations and outcomes emerge ‘in practice’. I examine how introduced species management is being done in the United Kingdom through detailed social scientific analyses of the processes, practices, and disputes involved in a series of management case studies. First, I demonstrate how some established approaches to the design and delivery of management initiatives can render them conflict-prone, ineffective and potentially unjust. Then, examining a disputesurrounding a state-initiated eradication of monk parakeets (Myiopsitta monachus), I show why and how ‘parakeet protectors’ opposed the initiative. I identify the significance of divergent evaluations of the risks posed by introduced wildlife; personal and community attachments between people and parakeets; and campaigners’ dissatisfaction with central government’s approach to the issue. By following the story of an unauthorised (re)introduction of Eurasian beavers (Castor fiber) to England, I show how adiverse collective has, at least temporarily, been united and empowered by a shared understanding of beavers as ‘belonging’ in the UK. I consider how nonhuman citizenship is socio-politically negotiated, and how the beavers have become enrolled in a ‘wild experiment’. Finally, through a multi- sited study of grey squirrel (Sciuruscarolinensis) control initiatives, I find important variations in management practitioners’ approaches to killing squirrels, and identify several ‘modes of killing’ that comprise different primary motivations, moral principles, ultimate aims, and practical methods. I identify multiple ways in which people respond and relate to introduced wildlife, and demonstrate how this multiplicity produces both socio-political tensions and accords. Furthermore, throughout this thesis I make a series of propositions for re-configuring the management of introduced species in ways that explicitly incorporate inclusive, constructive, and context-appropriate socio-political deliberations into its design and implementation.

Approximately 75% of the avian species in Utah use riparian habitats at some time during their life cycles and at least 80% of this habitat in Utah has been lost or altered since settlement; currently 0.6% of land cover in Utah is considered riparian. In 1992, with the support of Utah Partner's in Flight, the Utah Division of Wildlife Resources began a statewide neotropical migratory bird (NTMB) and habitat monitoring program to assess the status of bird populations at 31 sites. Additional sites (up to 52) were added in later years; bird and habitat assessments at 37 riparian sites have been continuously monitored since 1998. Using this long-term dataset, my primary study goals were to: 1) estimate abundance and densities of 38 focal avian species, 2) document and describe changes in riparian vegetation over time, and 3) investigate how these two processes are related by creating bird-habitat association models. Recent results from population trend analyses suggest that the patterns of annual variation and regional synchrony seen in riparian-dependent species groupings may be driven by landscape-wide effects on habitat. I developed riparian-bird habitat association models to better understand these large-scale effects using important variables specific to nine species of interest. I constructed classification and regression trees for three distinct foraging guilds to assess species-specific and community level habitat associations. Variables identified as important predictors of species density varied according to the species of interset. However, the variables selected by the classification models were consistent with each species life history strategies. Model results are intended to provide the framework for the development of management guidelines that will inform terrestrial riparian restoration and conservation efforts in Utah.