Monitoring and Research on Wading Birds in the Water Conservation Areas ofthe Everglades: The 1996 Nesting season

This project was initiated to continue monitoring reproductive responses of wading birds in the central Everglades, and to investigate two areas of research considered key to understanding and managing wading birds: nestling energetics, and factors affecting food availability. This report summarizes the first of two years of work. (101 page document

Factors affecting breeding status of wading birds in the Everglades.

This goals of this research and monitoring effort are to document nesting effort and roughly categorize success of nesting by wading birds in the central Everglades of Florida, and to investigate the causes of nonbreeding in a high proportion of the adult wading birds in the ecosystem The latter goal has focused on breeding of White Ibises (Eudocimus albus) and has been approached through 1) understanding the nutritional, behavioral, and hormonal aspects of normal breeding in a captive colony ofScarlet Ibises (considered conspecific to White Ibises) in central Florida, and 2) comparing breeding and nonbreeding wild White Ibises in the Everglades, in their physiology, nutritional state, breeding phenology, contaminant load, and hormonal status. This report covers work on this project between January and November, 2000. (81 page docoument

Now Hear This! Orientation and Behavioral Responses of Hatchling Loggerhead Sea Turtles, Caretta caretta, to Environmental Acoustic Cues

Although the visual and geologic orientation cues utilized by sea turtle hatchlings during seafinding, when they move from the nest to the sea after hatching, have been well studied, the potential for auditory stimuli to act as an orientation cue has not been well explored. Over the past several decades our knowledge of the auditory capacity of sea turtles has increased greatly, yet little is known about the biological significance of this sensory ability. To investigate whether hatchlings can use ocean sounds during seafinding, we measured the behavioral responses of hatchling loggerhead sea turtles (Caretta caretta) collected from nesting beaches in North Carolina to the presence of beach wave sound recorded on a nesting beach during the summer of 2015. The highest sound energy of beach waves occursHz, which overlaps with the most sensitive hearing range of loggerhead hatchlings (range of frequency detection: 50-1600 Hz, maximum sensitivity: 50-400 Hz). In our experiment, we placed turtles in a V-maze that isolated them from visual, vibratory, and chemical cues. One end of the V held a speaker producing beach wave sounds recorded from nesting beaches, while the other end held sound-reducing foam. We examined the phonotaxic behaviors of the hatchlings at two sound pressure levels (68 dB re: 20μPa and 64 dB re: 20μPa measured directly in front of the speaker). In the presence of the higher sound pressure level (68 dB re: 20μPa), hatchlings exhibited no phonotaxic response (p=1.0); yet, at the reduced sound pressure level (64 dB re: 20μPa), hatchlings exhibited a negative phonotaxic response (p=0.005). In control trials, hatchlings oriented to the two sides of the V-maze equally (p=0.701), suggesting the hatchlings in the lower volume treatment group were responding negatively to the sound. These results indicate the need for further auditory orientation experiments to better understand hatchling behavioral responses to environmental acoustic cues and to address possible impacts of anthropogenic beach sounds that have the potential to disorient hatchlings during seafinding

Variation in population synchrony in a multi-species seabird community: response to changes in predator abundance

Ecologically similar sympatric species, subject to typical environmental conditions, may be expected to exhibit synchronous temporal fluctuations in demographic parameters, while populations of dissimilar species might be expected to show less synchrony. Previous studies have tested for synchrony in different populations of single species, and those including data from more than one species have compared fluctuations in only one demographic parameter. We tested for synchrony in inter-annual changes in breeding population abundance and productivity among four tern species on Coquet Island, northeast England. We also examined how manipulation of one independent environmental variable (predator abundance) influenced temporal changes in ecologically similar and dissimilar tern species. Changes in breeding abundance and productivity of ecologically similar species (Arctic Sterna paradisaea, Common S. hirundo and Roseate Terns S. dougallii) were synchronous with one another over time, but not with a species with different foraging and breeding behaviour (Sandwich Terns Thalasseus sandvicensis). With respect to changes in predator abundance, there was no clear pattern. Roseate Tern abundance was negatively correlated with that of large gulls breeding on the island from 1975 to 2013, while Common Tern abundance was positively correlated with number of large gulls, and no significant correlations were found between large gull and Arctic and Sandwich Tern populations. Large gull abundance was negatively correlated with productivity of Arctic and Common Terns two years later, possibly due to predation risk after fledging, while no correlation with Roseate Tern productivity was found. The varying effect of predator abundance is most likely due to specific differences in the behaviour and ecology of even these closely-related species. Examining synchrony in multi-species assemblages improves our understanding of how whole communities react to long-term changes in the environment and suggests that changes in predator abundance may differentially affect populations of sympatric seabird species

The utility of hierarchical logistic regression for predicting repeated measures binary responses

This report will employ a hierarchical logistic regression model with mixed effects as an alternative to the traditional analysis of variance (ANOVA) approach that is often used when repeated observations are taken for each treatment. In the case of a binary response variable, ANOVA approaches typically require the user to first convert responses to an appropriate continuous variable, often a total score. The data used in this report include responses from 83 participants and are coded binary. Each participant was asked to make 12 separate decisions based on information received from videos of adult informants. The original purpose of the study was to determine the effect of subjects’ age (between-subjects) and of video characteristics (within-subjects) on the likelihood that children will make the correct choice. The purpose of this report was instead methodological in nature. The results of the hierarchical model are compared to the results of a traditional mixed design analysis of variance to illustrate the strengths gained from applying hierarchical models to data that includes repeated observations per subject and to compare results when the dichotomous nature of the outcomes is appropriately modeled.Statistic

Sea Turtle Response to Climate Change: Analyzing Current and Predicting Future Impacts on Populations, Habitat, and Prey Populations

With the prediction of devastating global climate change effects for the near future, scientists are expanding their research and understanding of some of the most severely affected organisms. Because sea turtles rely on both marine and terrestrial habitats for survival, and because coastal areas are already experiencing great losses due to sea level rising, human development, and pollution, all seven species are already listed as threatened under the Endangered Species Act. In this literature analysis, I examined the many factors that contribute to a sampling of the current sea turtle population status as well as scrutinized turtle adaptability to the changing environment. After developing a broad global view of the effects of climate change and human practices on worldwide sea turtle populations, I focused my study on the populations found in the waters of America as a continent, which included case studies of Costa Rica and Cape Cod Bay. In these two unique regions, various species experience diverse threats, including cold stunning, problems feeding, and nesting pressures. From this literature review in combination with my own independent research projects, I examined how some turtle populations would be affected by changing environmental and anthropological factors, and congruently formed my own conclusions and predictions about current population statuses and potential future implications. Though global climate change is causing sea level rise, and sand and air temperature increases, humans greatly impact both the vital marine and terrestrial environments of foraging and nesting sea turtles through ocean acidification, development, and over exploitation. The future of sea turtle population conservation and management relies on research and understanding of anthropogenic and climate change effects on marine and coastal habitats

Influence of the internal yarn nesting (shifting) on the local structural response of a satin weave composite: an experimental and numerical overview

The current paper emphasizes on the effect of internal yarn nesting (shifting) on the local structural response, such as, local stress - strain and the local damage of a satin weave composite. Detailed study of the variation of the local stress – strain behavior in the plies of a satin weave composite leads to the following conclusions: 1) local longitudinal strain in the plies of a satin weave composite is not influenced by the internal yarn nesting of the adjacent plies (position of the ply in the laminate); 2) local transverse stress as well as the weft yarn transverse damage is sensitive to the position of the ply in the laminate

Assessing the Consequences of Brood Parasitism and Nest Predation On Seasonal Fecundity in Passerine Birds

Brood parasites and nest predators reduce the seasonal fecundity and, hence, the population growth rates of their victims. However, most field studies do not measure directly how parasites and predators decrease seasonal fecundity, but instead measure the impact of these organisms on individual nesting attempts. Because a female may renest after losing a nest to predation, abandoning a parasitized nest, or successfully fledging a brood, knowing how brood parasites and nest predators reduce the number of offspring fledged from individual nesting attempts is not equivalent to knowing their impact on seasonal fecundity. We address this problem by developing a mathematical model that: estimates several parameters describing the natural history of this system, including the brood-parasitism rate, nest-predation rate, and probability of nest abandonment in response to a parasitism event; and extrapolates to seasonal fecundity from these parameters and others describing the length of the breeding season, the timing of events in the nesting cycle, and the productivity of parasitized and unparasitized nests. We also show how different researchers using different observational methodologies to study exactly the same population likely would arrive at noticeably different conclusions regarding the intensity of brood parasitism, and we provide mathematical formulas for comparing among several of these measures of parasitism. Our procedures extend Mayfield's method for calculating nest-success rates from nest-history data in that we simultaneously estimate parameters describing nest predation and brood parasitism, predict seasonal fecundity from these parameters, and provide confidence intervals on all parameter estimates. The model should make the design and interpretation of logistically difficult empirical studies more efficient. It also can be specialized to species affected by nest predators but not brood parasites. We use the model to analyze prairie Warbler (Dendroica discolor) and Black-capped Vireo (Vireo atricapillus) nesting data. We estimate the model's parameters for these species and use the resulting estimates to predict seasonal fecundity. For both species, the predicted seasonal fecundity closely matches the value measured directly.Integrative Biolog

Seroepidemiological studies of herpesvirus-associated diseases of marine turtles: Fibropapillomatosis and lung-eye-trachea disease

We have developed immunological tests that can identify marine turtles in Florida (green and loggerhead) that have been exposed to the LETV herpesvirus. The seroepidemiological data collected provides critical evidence about the relationship between infection with the FP-associated herpesvirus and the LETV herpesvirus. The data supports the hypothesis that LETV and FPHV infections are independent infections of marine turtles. The data shows that wild green turtles in Florida are exposed to the LETD-associated herpesvirus, which is the first description ofLETV infection in free-ranging marine turtles. To our knowledge, the antigenic proteins identified in this study are not only the first proteins from a reptilian herpesvirus to be cloned and expressed, but they represent the first reptilian herpesvirus proteins to be identified as immunogenic in their host species. (16 page document