Circadian rhythms dictate the timing of both once-in-a-lifetime adult emergence (eclosion) and daily locomotor activity rhythms in the flesh fly S. crassipalpis. Light cycles are considered the primary environmental time cue (zeitgeber), but the life history of S. crassipalpis suggests that temperature cycles (thermocycles) may also play a key role. This work evaluates the efficacy of thermocycling as a zeitgeber in S. crassipalpis. We found that shifting both light and temperature cycles of sufficient amplitude affect the phasing of eclosion and locomotor activity, but result in different patterns. Additional experiments suggest greater thermocycle sensitivity during the late metamorphic period and that thermocycling reduces variance in eclosion times. Taken together, these findings suggest that temperature cycles can be used by S. crassipalpis to time eclosion and adult locomotor activity, and that S. crassipalpis may be physiologically primed to use thermocycle information during metamorphosis.

Ruminant animals comprise the greatest proportion of herbivores around the world, provide essential ecosystem services and human consumable protein by consuming grass and human inedible dietary fiber. Herbivory pressure alters plant communities and species diversity, effectively making grazing animals ecosystem engineers in dynamic ecosystems. Development of advanced computer processing power coupled with biometric and ecosystem sensors may be employed in the internet of things framework to create an integrated information system designed to inform understanding of grazing system function and animal energy balance. Towards this end, I utilized Bos indicus / Bos taurus crossbred steers (n = 20) across two study sites each in consecutive calendar years and fitted them with GPS and accelerometer collar systems. Steers were grazed in improved grass pastures containing Tall Fescue (Festuca arundinacea) and Bermudagrass (Cyanodon dactylon). Forage samples were collected in a 20-m grid pattern at 35-day intervals to test nutritional composition, and NDVI maps were created using remotely sensed data collected using a UAV mounted camera system. In the first chapter, I utilize the movement ecology framework to investigate metabolic theory and animal behavior on energy budgets, then explore available technology to utilize in an integrative information system. In Chapter 2, I tested preprocessing and behavior collection methods used to train a machine learning randomforest classification model to predict animal behavior using triaxial accelerometers. Landscape functional scale and optimal sampling density is the primary focus of Chapter 3, where I explored the complex relationship between sampling regime, interpolation strategy, and landscape complexity, demonstrating that sampling density is a product of desired accuracy and landscape complexity. Finally, I focused on animal growth in Chapter 4, demonstrating the functionality of a walk-over-weigh system, and identified robust regression as the most accurate smoothing method to identify and remove spurious animal weights.

Mandated by the Sikes Act of 1960, natural resource managers work to manage the habitats and wildlife that are found on military installations in the United States and Territories. At Camp Edwards Military Training Reservation (hereby abbreviated to Camp Edwards), (Bourne, MA), such wildlife includes the state-protected eastern box turtle (Terrapene carolina carolina) and the declining prairie warbler (Setophaga discolor), which both occupy pine barrens. In 2020, natural resource managers at Camp Edwards noticed that eastern box turtles were being infected by myiasis, which occurs when flesh flies deposit larvae into the living tissue of a vertebrate host. In the literature, it has been documented that several ectothermic hosts respond to disease or parasite infection through a phenomenon referred to as ‘behavioral fever’ by moving to warmer locations to raise their internal temperature. Behavioral fever may clear the infection faster because higher body temperatures can induce parasite mortality or prevent secondary infections. However, it is unclear if myiasis induces behavioral fever in eastern box turtles or impacts other aspects of their behavior, such as habitat use. In Chapter 1, I compare behavior and habitat characteristics of myiasis infected and noninfected eastern box turtles at Camp Edwards. I radio-tracked 48 turtles weekly from May to August 2022. Upon capture, I recorded their infection status, shell surface temperature, and capture location habitat characteristics: understory vegetation, basal area, and canopy closure. I used generalized linear models and linear models to compare body condition indexes, shell temperatures, habitat use, and movement distances between infection statuses, sexes, and age classes. I found that myiasis infection had no significant effect on any variable other than shell surface temperature, which suggests infected turtles may be exhibiting behavioral fever. A second species of great concern at Camp Edwards are prairie warblers. Prairie warblers occupy early successional forests, which means that habitat management could have a direct impact on the distribution and abundance of this species. Despite declining populations regionally, prairie warbler populations at Camp Edwards have increased in the last few years. In Chapter 2, I analyze the effect of management projects (i.e., prescribed fire and mechanical projects) on prairie warbler colonization, extinction, and detection probabilities at Camp Edwards. I found that colonization was significantly predicted by the number of years since management and the proportion of the following vegetation cover types at a site: grassland, disturbed land, pitch pine – oak forest, and pitch pine – scrub oak community. I also found that extinction was significantly predicted by the proportion of pitch pine – scrub oak community at a site. Lastly, I found that detection probability was significantly predicted by the year of observation and the proportion of the following vegetation cover types: grassland, pitch pine – oak forest, and pitch pine – scrub oak community. These results can help managers predict how prairie warbler populations respond to management projects at Camp Edwards.

Responses of migratory birds to seasonal climate and long-term environmental changes have been a central theme of avian migration ecology. Atmospheric conditions (e.g., winds and thermals), climate, and land cover and land use (LCLU) are major factors influencing the flights of soaring birds. Soaring American White Pelicans (Pelecanus erythrorhynchos) (hereafter, AWPEs) migrate between the subtropical Gulf of Mexico (GOM) and the temperate Northern Great Plains. American White Pelicans are also economically important piscivorous birds, causing enormous damages to the commercial Channel Catfish (Ictalurus punctatus) aquaculture in the Southeastern US. My studies aimed to evaluate the effects of climate, wind, and LCLU on the geographic range distributions, seasonal movements, and annual survival of AWPEs. I used Bayesian integrated species distribution models to estimate the occupancy probability and space-use intensity of AWPEs at the breeding and non-breeding grounds in 2005, 2010, and 2015, respectively, with data from eBird, Breeding Bird Survey, and Christmas Bird Count. Decreases in wind speeds and surface net thermal radiation and increases in waterbodies, wetlands, and non-woody covers enhanced AWPE occupancy at both the breeding and non-breeding grounds. I used 72 GPS-tracked AWPE data to study circannual hourly movement speeds and seasonal home ranges of AWPEs from 2002 to 2012. American White Pelicans had shorter hourly movement distances and smaller seasonal home ranges in the Southern than Northern GOM during winters; however, the difference did not carry over to the shared breeding grounds during summers. Last, I built Bayesian integrated population models to estimate annual survival and population dynamics of AWPEs with mark-resight-recovery data and annual nest counts at Chase Lake, North Dakota, the US from 1960 to 2014. Increases in upward wind velocity during autumn migration enhanced hatch-year AWPE survival. Increased winter precipitation on the non-breeding grounds improved annual survival of yearling and adults. On the other hand, increased precipitation at the breeding grounds reduced annual survival of hatch-year AWPEs. My findings can help develop management plans for mitigating the economic damages of AWPEs by predicting what areas AWPEs may occupy with high abundances in the future changes in climate and LCLU.

As the earth’s landscape becomes increasingly urbanized, local wildlife must adapt to urban conditions or migrate to areas that are more rural. Urban wildlife face challenges such as direct loss of habitat, competition with non-native species, disturbance due to anthropogenic noise, and micro-climatic changes. Factors such as temperature, relative humidity, and noise affect the acoustical environment and may affect the ability of many animals, including birds, to communicate. Understanding how urbanization affects birds’ singing behavior is critical because singing often plays a vital role in attracting mates and defending territories. In addition, as global climate change occurs it will become increasingly important to understand the influence of abiotic factors such as temperature on the singing behavior of birds. Developing a deeper understanding of how those abiotic factors affect singing and other associated behaviors may help guide future conservation actions. Carolina Wrens are often used to study the role of singing in defending territories. They are also a common subject for ranging studies. However, surprisingly little research has been conducted on the factors influencing Carolina Wren song activity over the course of a day. No studies have compared the singing activity of Carolina Wrens in urban and rural environments. The purpose of this study was to compare the singing activity of Carolina Wrens in urban and rural areas. Specifically, this study looked for patterns in the timing of songs throughout the day and examined the effects of season, temperature, and anthropogenic noise on singing activity in urban and rural settings. I analyzed data from 4 SongMeter© SM2 data loggers (2 located at an urban park in Bowling Green, KY and 2 located at a rural preserve in Hart County, KY). The data loggers were programmed to record ambient sound for 3 minutes at the beginning of every hour. A Hobo® data logger was deployed with each SongMeter© SM2 data logger to record temperature and relative humidity at 15-minute intervals. One week of data in May and one week of data in July were analyzed. Both weeks had similar photoperiods, temperatures, and amounts of precipitation. For each recording, I documented the number of Carolina Wren songs I heard and a categorical assessment of the precipitation and anthropogenic noise due to traffic or machinery. I conducted Chi-square analyses to compare the seasonal or site-based observed frequencies of singing activity to the corresponding expected frequencies. In May, Carolina Wrens at the urban site sang more than their rural counterparts. Daily activity patterns were visually analyzed using the average number of songs detected for each hour’s sampling period. No Carolina Wrens were heard singing the hour before sunrise or the hour after sunset. In May, the dawn chorus lasted nearly twice as long as in July. Zero-inflated Poisson regressions were used to determine the correlations between Carolina Wren singing activity and temperature or anthropogenic noise. Carolina Wren singing activity had significant correlations with both variables.

Bottlenose dolphins exhibit fission-fusion social systems in which group size and composition change fluidly throughout the day. Societies are typically sexually segregated, and the quality and patterning of individual relationships in this social species shape the social structure of a population. Female dolphins usually have a large network of associates with whom they form recurring moderate bonds, while male associations are highly variable due to their mating strategies. Males employ one of two strategies; males may be solitary, and encounter and herd females individually, while others may form strong bonds with one to two other males and cooperatively herd individual females in the shape of a first-order alliance. Second-order alliances are more uncommon and have only been observed in Shark Bay, Australia, and more recently within the St. Johns River (SJR), Jacksonville, Florida. Given the inter-population variation in male mating strategies, greater documentation of social structure in neighboring populations along the Atlantic coast is needed. Therefore, chapter one documents the social structure of the Indian River Lagoon (IRL) estuarine system where dolphins have experienced recurrent cetacean morbillivirus (CeMV) epizootics. Although environmental disturbances can affect both social and mating systems, IRL dolphin sociality does not seem to be affected by the 2008 CeMV mass mortality event. Additionally, males only form first-order alliances within this population. Because multi-level alliances are unique to the SJR in this region, chapter two analyzes the stability and function of SJR alliances. Both first- and second-order alliances exhibited variation in stability, while alliance association appears dependent on female presence. Thus, SJR alliances likely function within a reproductive context. Together, this work provides insight into the social and mating systems of bottlenose dolphins, as well as the function of multi-level alliances at a relatively new study site.

Coral cover is in decline on a global scale, with increased mortality events being attributed to a number of global and regional stressors. While the impacts of global stressors (e.g. sea surface temperature rise, ocean acidification) are well documented, there is growing interest in identifying and understanding the impacts of regional stressors. The reason for this change in focus is that regional stressors can often work in combination, sometimes synergistically, with global stressors and that stressors on a regional scale tend to be more easily mitigated by management practices. One regional stressor that impacts a myriad of marine organisms in the southeastern United States is the annual red tide blooms produced by the dinoflagellate, Karenia brevis. Their impacts, along with the lipid soluble polyether neurotoxins they produce, termed brevetoxins, are well studied in economically important organisms, such as bivalves. However, little is known of their impacts on organisms that possess ecological importance, such as species of scleractinian coral. To address this gap in knowledge, a multifaceted study is discussed herein, which evaluated the effects of ecologically relevant concentrations of K. brevis and associated brevetoxins on different coral life history stages and coral species. The second chapter addresses the impacts of red tide on larval behavior, settlement and survival of the coral species Porites astreoides, as well as impacts of photochemical efficiency and oxidative stress within different coral species (P. astreoides larvae, P. astreoides adults, Acropora cervicornis, Cladocora arbuscula, and Phyllangia americana). The third chapter confers the use of broad-scale proteomic analysis to identify the cellular response of the non-model coral species, P. astreoides, following exposure to red tide. Coral larvae actively avoided both medium and high bloom conditions of K. brevis and brevetoxins, while percent larval settlement and survival were impacted following exposure to high bloom concentrations of K. brevis. Photochemical efficiency of in hospite Symbiodinium was reduced following exposure to both K. brevis and brevetoxin in P. astreoides larvae, as well as exposure to K. brevis in P. astreoides adults, while being unimpacted in A. cervicornis. Compared to controls, high bloom conditions resulted in an increase in biomarkers of lipid peroxidation in C. arbuscula. This was also seen in P. astreoides larvae at 24 hours; however, this difference was indistinguishable following 48 hours. Surprisingly, no other biomarker of oxidative stress analyzed were impacted. Broad-scale proteomic analysis of P. astreoides following exposure to red tide conditions revealed variable changes in proteome expression depending on if the corals were exposed to K. brevis or brevetoxins. Exposure to brevetoxins resulted in differential expression of proteins related to DNA organization, chromatin formation and transcription expression; while exposure to K. brevis resulted in differential expression of proteins related to redox homeostasis, protein folding, energy metabolism, and production of reactive oxygen species. The results of this study demonstrate the potential for annual red tide blooms to act as a regional stressor on coral species. They highlight the ability of red tide conditions to negatively impact coral at multiple life history stages and that the extent of these effects may be species specific. They also provide further incite of coral’s response to red tide exposure at the cellular level.

Adaptive radiation – the proliferation of species from a single ancestor and diversification into many ecologically different forms – has long been heralded as an important process in the generation of phenotypic diversity. However, the early stages of adaptive radiation are notoriously elusive to observe and study. In this dissertation, I capitalize on communities of introduced non-native Anolis lizards as analogues of early stage adaptive radiations. In Chapter II, I begin by reviewing the concept of “ecological opportunity” – a classic hypothesis put forward as a potential key to understanding when and how adaptive radiation occurs. In Chapter III, I investigate the mechanisms which allow for coexistence and community assembly among ecologically-similar species. To do this I investigate range dynamics and assembly patterns of introduced anoles on the oceanic island of Bermuda. I discover that interspecific partitioning of the structural environment facilitates species coexistence, however the order of species assembly was an important predictor of final community composition. In Chapter IV, I then investigate how interspecific interactions between coexisting species may drive phenotypic divergence. This is the process of character displacement, which has been widely hypothesized to be an important mechanism driving phenotypic divergence in adaptive radiations. To do this I investigate sympatric and allopatric populations of introduced Cuban brown anoles (Anolis sagrei) and Puerto Rican crested anoles (A. cristatellus) in Miami FL, USA. I identify morphological shifts in sympatry, driven by divergence in habitat use and decreases in abundance. This study provides evidence of how selection on both ecologically and sexually-important traits can both drive phenotypic divergence during character displacement. Finally, in Chapter V, after taking advantage of non-native species as model eco-evolutionary systems in previous chapters, I investigate the potentially harmful effects that their presence may have on vulnerable native biodiversity. To do this I investigate the conservation risk posed by newly-discovered populations of A. sagrei on Bermuda to Critically Endangered endemic Bermuda skinks (Plestiodon longirostris). Through a detailed analysis of habitat use, diet, population size, and morphology of A. sagrei on Bermuda, we conclude it likely poses a high conservation threat to P. longirostris through interspecific competition.

We study the equilibrium solutions of an integrodifferential equation used to model one-dimensional biological swarms. We assume that the motion of the swarm is governed by pairwise interactions, or a convolution in the continuous setting, and derive a continuous model from conservation laws. The steady-state solution found for the model is compactly supported and is shown to be an attractive equilibrium solution via linear perturbation theory. Numerical simulations support that the steady-state solution is attractive for all initial swarm distributions. Some initial results for the model in higher dimensions are also presented.

Trophic downgrading of ecosystems necessitates a functional understanding of trophic cascades. Identifying the presence of cascades, and the mechanisms through which they occur, is particularly important for seagrass meadows, which are among the most threatened ecosystems on Earth. Shark Bay, Western Australia provides a model system to investigate the potential importance of top-down effects in a relatively pristine seagrass ecosystem. The role of megagrazers in the Shark Bay system has been previously investigated, but the role of macrograzers (i.e., teleosts), and their importance relative to megagrazers, remains unknown. The objective of my dissertation was to elucidate the importance of teleost macrograzers in transmitting top-down effects in seagrass ecosystems. Seagrasses and macroalgae were the main food of the abundant teleost Pelates octolineatus, but stable isotopic values suggested that algae may contribute a larger portion of assimilated food than suggested by gut contents. Pelates octolineatus is at risk from numerous predators, with pied cormorants (Phalacrocorax varius) taking the majority of tethered P. octolineatus. Using a combination of fish trapping and unbaited underwater video surveillance, I found that the relative abundance of P. octolineatus was greater in interior areas of seagrass banks during the cold season, and that the mean length of P. octolineatus was greater in these areas compared to along edges of banks. Finally, I used seagrass transplants and exclosure experiments to determine the relative effect of megagrazers and macrograzers on the establishment and persistence of three species of seagrasses in interior microhabitats. Teleost grazing had the largest impact on seagrass species with the highest nutrient content, and these impacts were primarily observed during the warm season. My findings are consistent with predictions of a behaviorally-mediated trophic cascade initiated by tiger sharks (Galeocerdo cuvier) and transmitted through herbivorous fishes and their predators.