Climate change is threatening biodiversity, causing populations and species to adapt, or otherwise, become extinct. Sea turtles have survived dramatic climate changes in the past, however, due to a history of intense human exploitation, and the current anthropogenic threats, their current resilience may be jeopardized. The main pursuits of this thesis were to i) evaluate the resistance of green turtles to predicted climate change impacts, using a globally significant rookery, in Poilão, Guinea-Bissau, as a case study; and ii) assess key population parameters to inform the conservation management of this resource. As the work developed I additionally had the opportunity to study the dynamics of an emerging disease in a juvenile foraging aggregation from Puerto Rico, which contributed to a broader understanding of resilience in this species. Specifically, I investigate the nest site selection behaviour of green turtles, their nesting environment, and the outcomes for their offspring, at Poilão, and apply this information to infer on the resilience of this population under future scenarios of climate change. I explore the connectivity established by the dispersal of post-hatchlings from Poilão, followed by their recruitment to foraging grounds, to set the geographical context of this major population. Lastly, I model the dynamics of Fibropapillomatosis, which affects juvenile green turtles globally, and examine the potential for disease recovery. The green turtle rookery in Poilão shows some resilience to expected climate change impacts. This significant population likely contributes to all juvenile foraging aggregations along the west coast of Africa, and to some extent to those in South America. Currently, green turtles are capable of recovery from Fibropapillomatosis, however, the incidence of disease may be enhanced by climate change.

Ninho vazio (NV) corresponde ao período em que os filhos deixam a casa dos pais para se lançar a novos projetos. Já Síndrome do Ninho Vazio (SNV) é o termo comumente utilizado para se referir ao sofrimento emocional dos pais associado a esse período da vida. Objetivo: contribuir para a identificação e caracterização da Síndrome do Ninho Vazio em jogadores patológicos. O estudo baseouse na comparação entre um grupo de jogadores patológicos cujos filhos já tinham saído de casa (grupo NV; n=23), e outro cujos filhos ainda moravam com os pais (grupo de comparação; n=23), quanto às variáveis sociodemográficas, comportamento de jogo, comorbidades psiquiátricas, aspectos emocionais e adequação social. A intensidade da SNV foi avaliada por meio de entrevista semiestruturada. Potenciais diferenças de gênero também foram exploradas. Não houve diferenças significativas entre os grupos NV e de comparação em nenhuma das variáveis estudadas com exceção da condição econômica, melhor no grupo de NV, possivelmente, em função do menor número de moradores na casa. No grupo NV (n=23), houve associação significativa entre a idade que o(a) jogador(a) tinha quando o(a) filho(a) deixou a casa e a idade de início dos problemas com o jogo (r=0,630; P<0,001) e a idade de procura por tratamento (r=0,681; P<0,001). Adicionalmente, observouse associação entre intensidade da SNV e idade de procura por tratamento (r=0,435; P=0,038) e também entre intensidade da SNV e gravidade do jogo patológico (r=0,610; P<0,001) medida pelos critérios do DSMIV TR. Em relação ao gênero, percebeuse que as jogadoras (n=16), em comparação aos jogadores (n=7), apresentaram maior intensidade da SNV e maior sintomatologia depressiva e ansiosa, indicando que o sofrimento na saída dos filhos de casa é maior entre as mulheres jogadoras. A análise qualitativa demonstrou que 61% dos jogadores patológicos relataram sofrer com o ninho vazio, com menção a sentimentos negativos, como tristeza e depressão após a saída de casa dos filhos. Jogadores patológicos, ainda, relacionaram a saída dos filhos da casa com o comportamento do aumento de jogo, diminuição de jogo ou busca por tratamento. Estes resultados sugerem a necessidade de estudos com amostras maiores para uma compreensão mais ampla do impacto da Síndrome do Ninho Vazio no comportamento de jogadores patológicos, particularmente, entre mulheres jogadoras / Empty Nest (NV) is the period when the children leave the family home to launch new projects. Empty Nest Syndrome (SNV) is the term commonly used to refer to parents emotional distress associated with this period of life. The purpose of this work is to contribute to the identification and characterization of the empty nest syndrome in pathological gamblers by comparing a group of pathological gamblers, whose children have already left home (NV group; n= 23), with another whose children still live with them at home (comparison group; n=23), by looking at sociodemographic variables, gambling behavior, psychiatric comorbidities, emotional aspects and social adequacy. The intensity of SNV was evaluated through semistructured interviews. Potential gender differences were also explored. There were no significant differences between the NV group and the comparison group except for economic status, higher in the NV group, possibly due to the lower number of household members. In the NV group (n=23), there was a significant association between the age of the gambler when the child left home and the age of onset of gambling problems (r=0,630; P<0,001) and the age of seeking treatment (r=0,681; P<0,001). Additionally, we observed an association between SNV intensity and the age of seeking treatment (r=0,435; P=0,038) and also between SNV intensity and the severity of pathological gambling (r=0,610; P<0,001), as measured by the number of positive criteria in DSMIVTR. Comparing genders, we observed that female gamblers (n=16), showed higher SNV intensity and more depression and anxiety symptoms compared to male gamblers (n=7) indicating that the suffering caused by their children leaving home is higher among female gamblers. The qualitative analysis showed that 61% of pathological gamblers reported suffering with empty nest, with negative feelings, sadness and depression after their children left home. Pathological gamblers also related their children leaving home whit increased gambling behavior, decreased gambling behavior or treatment seeking. These results suggest the need for studies with larger samples to broaden the understanding of the impact of empty nest syndrome in the behavior of pathological gamblers, particularly among female gamblers

Nest box programs provide supplemental nest sites for American Kestrels, Falco sparverius. When the availability of nest sites is a limiting factor, the addition of nest boxes can increase local breeding populations. These programs also facilitate the collection of data on breeding kestrels. This study focuses on an American Kestrel (Falco sparverius) nest box trail along Interstate 26 in northeastern Tennessee during the breeding seasons of 1998, 1999, 2000, 2003, 2004, 2006, and 2009. Productivity measures and reproductive success of nesting birds are provided and compared to other programs. The data are analyzed across years and by box. Finally, a discussion of the habitat surrounding the most and least active boxes provides recommendations for increased efficiency of the program.

The structure of a protein molecule is highly correlated to its function. Some diseases such as cystic fibrosis are the result of a change in the structure of a protein so that this change interferes or inhibits its function. Often these changes in structure are caused by a misfolding of the protein molecule. To assist computational biologists, there is a database of proteins together with their misfolded versions, called decoys, that can be used to test the accuracy of protein structure prediction algorithms. In our work we use a nested graph model to quantify a selected set of proteins that have two single misfold decoys. The graph theoretic model used is a three tiered nested graph. Measures based on the vertex weights are calculated and we compare the quantification of the proteins with their decoys. Our method is able to separate the misfolded proteins from the correctly folded proteins.

The red-headed woodpecker is a primary cavity excavator found throughout the Eastern Deciduous Forest and parts of the Great Plains. Although widespread, the red-headed woodpecker is generally considered uncommon, with patchily distributed populations. Over the past 50 years, this species has experienced precipitous, range-wide declines. The red-headed woodpecker uses a variety of cover types to meet resource needs across the annual cycle, ranging from oak savannas and wetlands, to mature beech forests and urban parks. Given their apparent adaptability to such a wide range of habitats, causes of declines are perplexing. To understand and stem declines, recent studies have focused on quantifying this species’ habitat requirements. Most of these studies have focused on a single cover type, often open forests, during the breeding season. However, effective management requires comprehensive knowledge of red-headed woodpecker habitat needs in a variety of cover types across the annual cycle. My thesis seeks to address this knowledge gap. I studied red-headed woodpecker habitat selection during both the breeding and non-breeding seasons at Fort A.P. Hill (FAPH) in Caroline County, Virginia. FAPH contains a variety of cover types that red-headed woodpeckers are known to use for breeding and overwintering, including: wetlands, open forests and closed forests. In Chapter 1, I investigated winter roost-site selection of red-headed woodpeckers in a burned forest stand. My study was the first to quantify winter habitat selection for this species. My aim was to identify variables driving winter roost-site selection at two relevant spatial scales, and estimate their parameter weights using logistic regression. I found that red-headed woodpeckers preferred habitat around the roost tree that contained a higher basal area of snags and mast-producing trees. They differentially selected roost trees based on taxon and decay state. My results indicate that managers should adopt practices that promote snag generation and retention, and mature oak recruitment. In chapter 2, I focused on red-headed woodpecker breeding season habitat requirements, as many other studies have done. However, unlike other studies that investigated habitat selection within a single cover type, I found and characterized nest-sites in three distinct cover types (wetlands, closed forests, open forests). I used a comparative approach to identify cover-type specific nest-habitat thresholds at the landscape, patch and tree scales using boosted regression trees (BRT). Although models at the landscape scale inadequately discriminated between nest and available sites, models at the patch and tree scales achieved excellent discrimination ability. I found that red-headed woodpeckers are consistent in their preference for a number of habitat features at the patch (high medium/large snag density, open canopy) and tree (large diameter tree with less bark) scales, irrespective of cover type context. However, I also found cover-type specific habitat preferences at the patch scale, indicating red-headed woodpeckers are flexible in their selection of features surrounding the nest and responsive to the broader habitat context. My findings suggest that there are a number of habitat features that facilitate breeding for red-headed woodpeckers generally, and management that promotes these features will be effective in a variety of habitat contexts. They also indicate that management can be tailored to provide the most suitable habitat for each of these three commonly used cover types. Together, Chapters 1 and Chapter 2 expand our knowledge of this declining keystone species’ habitat needs across the full annual cycle. But there is still much to know. The choices of habitat selection have consequences. Determining the conditions under which habitat features function to either help or harm populations is a necessary next step. While not a part of this thesis, I am currently investigating the factors that drive nest success among cover types, linking breeding-site selection to population dynamics. I also have behavioral data that will help reveal the mechanisms that either facilitate or constrain the exploitation of food resources across cover types. Finally, the red-headed woodpecker is a facultative migrant that often shifts habitat associations to take advantage of seasonally available resources. Data from my point count surveys—conducted over two successive winter and summer seasons—allow for development of dynamic occupancy models. Modeling shifts in occupancy across seasons will show the habitat factors underlying seasonal shifts. Site-specific differences in colonization, extinction and frequency of occupancy, within seasons but across years, will further our understanding of what constitutes habitat quality for this species, in both the breeding and non-breeding seasons.

Selecting a nest site is an important decision for waterfowl. Because most nest failure is due to depredation, the primary selective pressure in choosing a nest site should be to reduce depredation risk. This task is difficult because predators use differing tactics to locate nests, such as olfactory or visual cues. I investigated several components of waterfowl nest-site selection and success on sites with shelterbelts (planted tree-rows) in North Dakota, during the 2006 and 2007 nesting seasons. I found that meteorological conditions impacted nest depredation; artificial nests were more likely to be depredated when either temperature or dew point was high. These meteorological conditions should improve foraging efficiency for olfactory predators by increasing odor concentration. Waterfowl selected nesting sites with greater visual concealment than random locations (lateral concealment). However, the only difference found between successful and depredated nests was lateral dispersion, an olfactory concealment characteristic. Nest density was higher in areas without shelterbelts than in areas near shelterbelts. Nest success for waterfowl decreased as shelterbelt height increased. Other shelterbelt characteristics, like porosity and orientation, did not affect nest success or nest density. Given that nest predators differ in foraging habitat, temporal patterns of activity, and searching modalities, nest site characteristics that conceal the nest from 1 predator species may increase its vulnerability to another predator. For instance, risk due to olfactory predators should be reduced near shelterbelts because locating nests would be more difficult as turbulence is generated by the shelterbelts. Concomitantly, shelterbelts could also increase the presence of visual predators, by providing nesting sites and vantage points. In my study, any benefits shelterbelts provide in reducing nest depredation by olfactory predators may have been offset by increasing nest depredation from visual predators. Hence nesting near shelterbelts was neither a liability nor a benefit to ducks.

No description available.

No description available.

Abstract not available

Interactions between nesting birds and invertebrates are a common, yet poorly understood ecological phenomenon. Many of these types of interactions are close and prolonged, and therefore potentially critical to one or both of the species involved in the interaction. However it is unusual for the nature of the interaction to be evaluated in a manner that reveals the impact of the relationship on both parties to the interaction. This study examines two relationships between nesting birds and invertebrates, both of which involve the hooded parrot (Psephotus dissimilis), a small grass parrot that inhabits the tropical savannas of northern Australia. ¶ The field-work for this project was conducted over two parrot breeding seasons in 2006 and 2007 near Katherine, Northern Territory, in the Australian dry tropics. In chapter II, I present data on the breeding biology of the hooded parrot as background for the study that follows. Nest building commenced in January, with peak activity in February and the last chicks fledged in April. Fifty three active nests were located. The mean number of eggs laid per nest was 4.5 (s.d. ± 0.9), of which 3.0 (± 1.79) hatched and 2.0 (± 2.0) fledged. Clutches were laid asynchronously over a period of a week and chicks remained in eggs for 18.6 (± 1.95 days). Chicks were 29.2 (± 2.9) days old when they fledged from the nest. These data are typical for Australian parrots. ¶ In chapter III, the unusual nature of the parrot’s nest site is examined. Many species of bird nest in natural cavities or those they excavate. Whilst cavity nesters as a whole experience increased nesting success, the greatest success is experienced by species that can excavate their own nests. Certain arboreal cavity nesters, such as woodpeckers, require extensive morphological adaptation for this behaviour, but this has not occurred in Australia, despite competition among birds and a suite of arboreal mammals for naturally occurring cavities. Some species, however, have adapted their behaviour to make use of substrates that are not as hard as wood. Hooded parrots excavate nests in terrestrial termitaria, releasing them from competition for limited arboreal cavities. However, I show that only termitaria with a high level of termite activity, and which are more than two metres tall, are suitable, and that the parrots exhibit a strong preference for the cathedral mounds of Nasutitermes triodiae. Nests placed in highly active mounds had a significantly higher success rate than those in mounds where activity was somewhat lower, suggesting that the behaviour is adaptive. ¶ The thesis then shifts focus from the parrot to its nest symbiont, first describing the species involved in the interaction in chapter IV, and then its behaviour in the nests of hooded parrots in chapter V. Trisyntopa neossophila sp. n. (Lepidoptera: Oecophoridae) was reared from the nest of the hooded parrot and described using morphological characters. Aspects of its biology are reported and similarities to the biology of Trisyntopa scatophaga found in the nests of the golden-shouldered parrot (Psephotus chrysopterygius) are discussed. The possibility that a moth was associated with the extinct paradise parrot (Psephotus pulcherrimus) is considered in the light of the phylogenetic relationships between the parrots. ¶ Trisyntopa neossophila is an unusual moth whose breeding cycle is shown to be closely synchronised with the hooded parrot. T. neossophila is one of three coprophagous, nest dwelling moths in the genus Trisyntopa. True coprophagy is rare in the Lepidoptera, although some species occasionally consume faeces to gain rare nutrients. T. neossophila lays its eggs in the nest of hooded parrots so that larvae hatch in synchrony with the hatching of the parrot’s eggs. The larvae spend their larval period in the nest and exclusively consume the excrement of the nestling parrots. When the parrot chicks fledge, the larvae move to the walls of the nest cavity to pupate, emerging the following wet season to repeat the process during the next parrot breeding season. ¶ With a description of the ecology of both species involved in the nesting symbiosis, chapter VI reviews the literature surrounding other interactions between nesting birds and invertebrates. A large number of birds are shown to nest in, or in close proximity to, structures made by invertebrates and avian nesting material provides a reliable shelter for many invertebrate species. However, the nature of such relationships has rarely been experimentally demonstrated. I propose that in order to understand the nature of these relationships they need to be explored within the theoretical framework of community ecology. Putative commensal and parasitic relationships have all been documented in the bird/invertebrate nesting literature, yet researchers, with few exceptions, repeatedly overlook the impact that these relationships are having on the invertebrate, at best assuming the nature of its impact, but more often ignoring its impact entirely. Here I present a framework for formulating hypotheses to ensure that the nature of the relationship can be identified. Only by explicitly stating the level of organisation at which the experiment is to occur (individual or population), identifying the net cost or benefit of the interaction, the range of conditions under which such costs or benefits would apply and the spatial and temporal context in which they apply, can an investigator expect to recognise and describe the often complex nature of these relationships. ¶ While parasitic and commensal relationships between nesting birds and invertebrates are commonly reported, mutualisms between birds and invertebrates have not been reported. Despite this, candidates for this type of relationship exist. Chapter VII uses the framework outlined in the literature review (chapter VI) to experimentally examine the relationship between the hooded parrot and Trisyntopa neossophila. By manipulating the populations of moth larvae in a sample of hooded parrot nests, we sought to establish the impact of the relationship on each species. The moth depends on the parrot for provision of shelter and a reliable food source. The parrot however, was neither benefited nor harmed by the interaction in terms of short term reproductive output or chick growth, although differences between the experimental and control nests were noted. The relationship between the hooded parrot and T. neossophila, at least during the study period, is therefore concluded to be commensal. ¶ Collectively, the chapters of this thesis explore the complicated interactions between species. The dependence of the moth on the parrot and the parrot on the termite, demonstrate the importance of understanding interactions between species in a manner that reveals the impacts of the interactions, the range of conditions under which they would apply and the level of organisation at which they apply, as outlined in chapter VI. The dependence of the animals in this study on each other makes them more vulnerable to extinction than previously thought. Whilst this may not be immediately significant for the hooded parrot/T. neossophila system, which is thought to be secure, the ecologically similar system on the Cape York Peninsula, involving the golden-shouldered parrot and its nest attendant moth Trysintopa scatophaga, is vulnerable to extinction and subject to intensive management to ensure its persistence. This study brings new information to the management of the golden-shouldered parrots and urgently recommends increased protection for Trysintopa scatophaga.