Thesis (M.S.)--Oregon State University, 1981. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 36-39). Also available via Humboldt Digital Scholar.

Thesis (M.S.)--Wildlife and Fisheries Sciences. South Dakota State University, 1988. / Includes bibliographical references (leaves 77-82). Available also on the Internet.

Ground-nesting birds nesting in the open have to cope with an extreme thermal environment. Their nests egos and chicks are often located within the boundary layer and are exposed to, direct solar radiation. In preventing eggs and chicks from overheating, adult incubating birds expose themselves to severe heat loads. This study looked at two aspects of this system. Firstly, we examined the role of behaviour in the thermoregulation of breeding crowned plovers (Vanellus coronatus). We then examined the development of independent thermoregulation in hatchling crowned plovers. This study assessed the role of shading behaviour in the thermoregulation of incubating crowned plovers (Vanellus coronatus). Shading behaviour was shown to have no direct benefit for eggs, at times even causing eggs to rise close to lethal levels. Instead, shading behaviour played an important role in maintaining incubating bird temperatures at a constant level. We therefore suggest changing the term "shading" to "standing" behaviour. In addition, core body temperatures of free-ranging adult incubating birds and their eggs were examined on both a daily and a seasonal scale. A range of core bird temperature of 8.8° C was measured during the course of the study. Both daily and seasonal differences in core bird temperature occurred. Daily differences are a result of daily circadian rhythms while seasonal differences are explained by changes in ambient temperature. Both daily and seasonal differences in egg temperatures also occurred. The concept of optimum incubation temperature for a species is therefore reconsidered. Differences between and within species may not be as a result of phylogenetic differences as previously reported, but may be as a result of relatively short-term changes in response to ambient temperature changes. The validity of using taxidermic models in thermoregulatory studies was assessed by comparing data collected using both real and model birds. No direct correlations were found between real and model eggs and birds. This suggests that the patterns seen in models may not adequately reflect short term changes that occur in the real system, thus reducing the ability to use such data to make broad generalizations about thermoregulation in general. The models are, however, useful in providing insight into the heat load an animal carries under different environmental conditions, and in estimating the overall, long-term effects of metabolic heat production in a real bird and egg. Secondly, we looked at the development of thermoregulation in a ground- nesting shorebird. An issue of general importance with regard to the ontogeny of precocial chicks is the timing of the onset of independent thermoregulation. We wanted to determine the mass at which crowned plover (Vanellus coronatus) chicks are able to thermoregulate independently in both the laboratory and the field, and to compare this to predicted values previously reported. Laboratory reared chicks attained independent thermoregulation at a mass of 65 g, while chicks in the field did so at a mass of 55 g. This is 33 - 39% of adult body mass, or approximately twice that predicted for a 167 g shorebird chick. Development of homeothermy represents a trade-off between growth rate and development of thermoregulation. Efficient use of behavioural thermoregulation, coupled with predation risks, allows more energy to be channelled into growth early on in the development of crowned plover chicks. Development of homeothermy in anyone taxonomic group may not, therefore, always be described by a single function. Instead , differences reflect a balance between growth rate, development of physiological thermoregulation, use of behavioural thermoregulation, predation risk, and environmental factors. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

Plovers was compared with particular reference to breeding biology, feeding ecology and habitat preference. Crowned and Blackwinged Plovers coexisted in mixed flocks in grasslands which aided predator detect ion and defence against predators. Lesser Blackwinged Plovers were opportunistic in their use of habitat and were found in habitats ranging from the muddy edges of pans to woodlands. Body size was found to have an important effect on the breeding biology of these birds, affecting incubation behaviour and reproductive pattern. The behaviour of Lesser Blackwinged Plovers differed considerably from that of Crowned and Blackwinged Plovers. Crowned and Blackwinged Plovers appear to constitute a superspecies on account of their behavioural and morphological similarities while the Lesser Blackwinged Plover is possibly closely related to the ancestral stock of the genus Vanellus. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg.

"April 1994"--P. (4). / Shipping list no.: 94-0334-P.

eBird, a citizen-science program developed by the Cornell Lab of Ornithology and National Audubon, allows users to enter bird sightings from around the world in order to develop a large scale data set for research. This study seeks to analyze eBird data and methods in order to determine if the data collected is robust enough to be usable as a basis for habitat management and, if so, to what extent. This is accomplished through a comparison of Piping Plover (Charadrius melodus) (a threatened shorebird of management concern) counts, trends, and methodologies made through a survey following a strict protocol versus data collected by eBird in three different areas (Bolivar Flats, Apfel Park, and San Luis Pass). Using descriptive statistics such as mean counts, counts adjusted for effort, and frequency, and confirming with Kruskal-Wallis tests, variation was found between eBird and survey data. eBird contained lower counts of Piping Plovers and a lower sighting frequency than survey data. When adjusting counts as a function of effort, similar results were found. Piping Plovers were found not to occur frequently at Bolivar Flats (9 birds over 2 surveys), while Apfel Park and San Luis Pass showed similar but inconclusive results. This study ultimately determined that, while of great use on large scales, use of eBird data on the local level, should be used with caution. Further study should be done to investigate sources of variation and methods to increase the effectiveness of eBird on small scales.

Anthropogenic habitat change is the most important factor contributing to global losses in biodiversity. Ecological research can help identify the mechanisms that cause these declines by relating environmental characteristics to wildlife habitat use and productivity. Such studies can contribute to the design of land-use practices that enhance wildlife populations in conservation areas and promote efficient compromises between human use and conservation. The conflicts between human-use and conservation are particularly evident in coastal areas, which have enormous economic value and are thus coveted areas for development. Human-use can alter the habitat quality and affect coastal taxa, such as shorebirds. iv In this study I examine the breeding ecology and conservation biology of a beach-nesting, near-threatened shorebird, the Malaysian plover Charadrius peronii, which breeds on coastal areas throughout Southeast Asia. Although nearly half of the threatened shorebird species breed in tropical areas, little research has been conducted on the conservation and ecology of these species. My study is the first detailed research conducted on the Malaysian plover. It contributes to a better understanding of the environmental factors constraining breeding strategies in the tropics and identifies key mechanisms linking anthropogenic habitat change and wildlife populations. I used behavioural approaches to collect a wide range of data over a short-time period in order to describe the breeding ecology of Malaysian plovers, evaluate different types of constraints, identify anthropogenic impacts and provide recommendations on management approaches to mitigate the impacts of habitat change. Malaysian plovers have long breeding seasons, high site fidelity, complete biparental care and can nest multiple times in a single year. In contrast to shorebirds in Arctic environments, where fecundity is limited by the brief pulses of high seasonal productivity, Malaysian plover fecundity appeared to be constrained more by habitat availability rather than time. Malaysian plovers began defending territories several months prior to the breeding seasons and nested in the same habitats even if there were significant reductions in habitat quality throughout the course of the breeding season. In the Gulf of Thailand tourism-related habitat change that narrows beaches, alters vegetation structure and enhances human disturbance levels reduce habitat availability and breeding success. Enhanced vulnerability of clutches to tidal flooding, chicks to predation, exposure of eggs to heat and chicks to predation may be key mechanisms leading to these effects. Moreover Malaysian plovers had a density-dependent decline in breeding success. Consequently, if birds are displaced from preferred beaches due to habitat change, then breeding success may be reduced in otherwise high quality habitat as plovers crowd into remaining beaches. When people approach nesting or chick-rearing plovers, one or both of the adults will leave the clutch or chicks to conduct distraction displays. Compared to holarctic species, tropical shorebirds may be more vulnerable to the fitness impacts of human disturbance because even short periods of exposure to direct sunlight can cause clutch failure, whereas eggs are resistant to chilling. These results suggest that the environmental and ecological conditions in tropical regions may affect the susceptibility of breeding shorebirds to fitness impacts of anthropogenic disturbance and habitat change. Future research should assess cumulative impacts of habitat change by conducting multispecies studies and include wintering or stopover shorebirds. As my research was conducted in the best Malaysian plover breeding habitat in Thailand, it is important to assess the generality of my results by comparisons to other regions or across several years in which there may be a different range of predators or prey. Finally, it is important to note that these types of ecological conservation studies are only a first step towards successful protection of threatened species. The greater challenge is to tackle the ultimate socio-economic and institutional factors that limit the effectiveness of protected areas and contribute to the number of environmentally destructive coastal development projects.

No description available.

I studied the piping plover on Assateague Island during the 1986 and 1987 breeding seasons. In 1987, I estimated the population to be 69 pairs. During both years, plovers nested on only a few portions of the island. I think that this pattern of nesting was determined by the distribution of three types of foraging habitats: bayside mud and sand flats, saltwater pools formed by storm tides, and a drawn down waterfowl impoundment. Reproductive rates were lower than two recent estimates of the level necessary to maintain a stable population. The primary problem was poor nest success and the leading cause of nest loss was nest predation by red foxes (Vulpes vulpes) and raccoons (Procyon Iotor). I was not able to identify factors responsible for chick mortality, but my data show a relationship between chick survival and foraging habitat. Broods feeding on bayside foraging areas had a much higher survival rate than broods which did not have access to these areas. Management efforts should focus on reducing nest predation. Recent experiments have indicated that predator exclosures constructed around individual nests can be used to reduce nest predation. These exclosures should be tested on Assateague. Future research efforts should focus on the role of foraging habitat in breeding site selection and the relationship between chick survival and the type of foraging used. / Master of Science