Download or read book Behavioral and Demographic Responses to Environmental Change in a Pond breeding Amphibian written by Gabriel Maturani Barrile and published by . This book was released on 2021 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding how organisms respond to environmental change is a fundamental challenge in ecology and wildlife management. We studied boreal toads (Anaxyrus boreas boreas) in western Wyoming, USA to investigate behavioral and demographic responses to infectious disease and several forms of habitat change. Boreal toads in this region were challenged with Batrachochytrium dendrobatidis (Bd), a fungal pathogen implicated in global amphibian declines. Toads experienced changing habitat conditions as the result of cattle grazing and stochastic variability in spring flooding, whereby high snowmelt runoff collapsed beaver dams and destroyed critical breeding habitat. In Chapter 1, we used radio-telemetry to track the habitat choices of adult toads (n = 42) during the summer months of 2016. Boreal toads infected with Bd selected warmer, more open habitats, which were associated with elevated body temperature and the subsequent clearing of infection. In Chapter 2, we used a five-year (2015–2019) mark-recapture dataset to investigate the dispersal of adult toads (n = 1100) between breeding ponds. Boreal toads more often departed from low quality breeding ponds (without successful metamorphosis) and settled in high quality breeding ponds (with successful metamorphosis). Movement decisions were context-dependent and associated with pond characteristics altered by beaver dam destruction. In Chapter 3, we used our mark-recapture dataset to explore the interplay between disease, livestock grazing, climatic variation, and annual survival of adult boreal toads (n = 1301) during 2015–2019. Cattle grazing generated conditions less conducive to Bd growth by reducing vegetation cover and creating warmer microclimates. Higher winter snowpack resulted in shorter spring breeding seasons, which were associated with lower Bd prevalence. Boreal toads infected with Bd suffered increased mortality, but only when temperatures during summer months were relatively cool. In Chapter 4, we examined the potential effects of livestock grazing and pond characteristics on tadpole survival across 20 breeding sites during May–September 2018. Cattle grazing reduced vegetation cover in and around breeding ponds, which may negatively influence metamorphosis by decreasing feeding sites and escape cover for tadpoles and/or increasing exposure to harmful UV radiation. Overall, our results suggest that disease is an important selective agent on animal habitat and space use, whereby some wild animals can proximately modify habitat choices in response to infection status. This behavioral tactic may only be effective at higher temperatures, however, suggesting that individuals at cooler, higher elevations face increased risk of disease-induced mortality compared to conspecifics at warmer, lower elevations. We demonstrate that some animals respond to stochastic variation in habitat quality via adaptive breeding dispersal. Creating new suitable environments (e.g., facilitating beaver activity in our system) and increasing the structural connectivity among patches will be important conservation tools for enabling dispersal to higher quality habitats. We further show that the effects of climatic variation can manifest via altered season lengths that influence ecological interactions such as host-pathogen dynamics. Future investigations of wildlife responses to disease therefore may benefit from considering the indirect effect of weather on host phenology. Finally, we demonstrate that vital rates across a species’ life cycle can be shaped by different extrinsic stressors, such that careful study of multiple stressors across several life-stages provides a more complete understanding of overall population effects and can help target conservation actions.

Download or read book Amphibian and Reptile Adaptations to the Environment written by Denis Vieira de Andrade and published by CRC Press. This book was released on 2017-12-19 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite their diversity, amphibians and reptiles share many physiological traits, such as their dependence on external heat sources for body temperature regulation, that are of pivotal importance to their ability to cope with the environment. Considerable variation in physiological capabilities exists in these groups and often can be related to seasonal and geographic differences in environmental parameters. This book provides a comprehensive and integrative view of the interplay between physiology and behavior in amphibians and reptiles, leading to a better understanding of the subject. The book covers topics that have recently been in the spotlight for scientific research on the physiology, behavior, and conservation of amphibians and reptiles. It brings together recent information from a range of disciplines that address critical topics for understanding their biology. As these studies are scattered across articles in specialized journals, this book provides a single and expanded source summarizing such advancements. Amphibian and Reptile Adaptations to the Environment: Interplay Between Physiology and Behavior maintains a solid scientific basis for the biological topics covered. However, it presents the material in a clear and direct manner so that it is accessible even to non-biologists interested in the basic biology, behavior, and ecology of these animals as well as how these elements are connected to their conservation.

Download or read book Carryover Effects of Hydroperiod Length Neonicotinoid Pesticide Exposure and Predation Risk in a Pond breeding Amphibian written by Cassandra Marie Thompson and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphibian species are declining globally, and are now one of the most threatened taxon, with over one-third of global amphibian species being listed by IUCN as Threatened, Endangered, or Critically Endangered. Foremost, the effects of climate change are pervasive across both terrestrial and aquatic systems, and synergies with other threats are actively contributing to current declines and local or global extinctions. Whether a species will be able to buffer itself against novel climate conditions and interactions with other environmental stressors will largely depend on their ability to respond through physiological and behavioral plasticity. Assessing these responses and their demographic consequences is particularly challenging for species with complex life cycles, such as amphibians, for which environmental variation can have different effects on demographic parameters across life stages. Environmental variation during development can have profound, variable effects on an organism's phenotype, fitness, morphology, and physiological attributes. As such, carryover effects from one life stage to another occur when an individuals’ early life experiences affect their fitness, performance, and demographic parameters at a later life stage. Aquatic stressors, such as temperature regimes, predation risk, pool hydroperiod, and exposure to contaminants often have sublethal impacts on the developmental environment of larval amphibians, which can affect morphology, behavior, and physiology throughout development and into later life stage. My doctoral research uses a range of meso- and microcosm experiments with larval and juvenile wood frogs (Rana sylvatica) to investigate (1) whether the innate plasticity of pond-breeding amphibians allows them to demographically compensate for negative carryover effects of various environmental stressors experienced during the larval stage and (2) how particular stressors may interact and cause synergistic, additive, or antagonistic effects on larval development and carryover effects. First, I investigated the carryover impacts of pond drying (hydroperiod length) on the development, survival, morphology, and locomotor performance of larval and juvenile frogs. Shorter hydroperiods resulted in lower larval survival and smaller sizes at metamorphosis. Post-metamorphic frogs from longer hydroperiod treatments grew faster and larger compared to individuals from shortest hydroperiods and had higher locomotor performance during endurance trials under various temperature and dehydrations regimes. Second, I quantified the developmental and behavioral effects of pond drying and sublethal neonicotinoid pesticide imidacloprid exposure on larval wood frogs.

Download or read book The Ecology and Behavior of Amphibians written by Kentwood D. Wells and published by University of Chicago Press. This book was released on 2010-02-15 with total page 1162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Consisting of more than six thousand species, amphibians are more diverse than mammals and are found on every continent save Antarctica. Despite the abundance and diversity of these animals, many aspects of the biology of amphibians remain unstudied or misunderstood. The Ecology and Behavior of Amphibians aims to fill this gap in the literature on this remarkable taxon. It is a celebration of the diversity of amphibian life and the ecological and behavioral adaptations that have made it a successful component of terrestrial and aquatic ecosystems. Synthesizing seventy years of research on amphibian biology, Kentwood D. Wells addresses all major areas of inquiry, including phylogeny, classification, and morphology; aspects of physiological ecology such as water and temperature relations, respiration, metabolism, and energetics; movements and orientation; communication and social behavior; reproduction and parental care; ecology and behavior of amphibian larvae and ecological aspects of metamorphosis; ecological impact of predation on amphibian populations and antipredator defenses; and aspects of amphibian community ecology. With an eye towards modern concerns, The Ecology and Behavior of Amphibians concludes with a chapter devoted to amphibian conservation. An unprecedented scholarly contribution to amphibian biology, this book is eagerly anticipated among specialists.

Download or read book Behavioral Choice and Demographic Consequences of Wood Frog Habitat Selection in Response to Land Use written by Tracy A. Green Rittenhouse and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Land use is a pervasive form of disturbance affecting natural systems on Earth. My dissertation research is set within the context of a large scale project referred to as Land-use Effects on Amphibian Populations (LEAP), where researchers in Maine, Missouri, and South Carolina are determining the effects of timber harvest on the persistence of amphibian populations. The purpose of my dissertation research was to define adult wood frog nonbreeding habitat in continuous oak-hickory forest and in response to timber harvest. I asked research questions that address the two components of habitat selection: 1) the behavioral choice, and 2) the demographic consequences of that choice. To document behavioral choice, I allowed adults to move freely throughout the circular experimental timber harvest arrays (164 m radius) by using standard radiotelemetry techniques. Prior to timber harvest, I found that wood frogs were not distributed equally throughout oak-hickory forest. Adults used drainages as non-breeding habitat. In addition, the number of frogs that migrated to a specific drainage correlated with the distance between the pond and the drainage. Following timber harvest wood frogs avoided clearcuts and increased movement rates in response to timber harvest. Further, I confirmed the consistency of this behavioral response by conducting experimental displacements and found that adults exhibit site fidelity to non-breeding habitat. Frogs displaced to the center of clearcuts evacuated the clearcuts in one night of rain and 20 of 22 frogs displaced back to the pond returned to the same drainage. To determine demographic consequences, I estimated survival of frogs constrained within microhabitats. Desiccation risks for frogs located on forested ridgetops or in exposed areas within clearcuts were severe. Brushpiles within clearcuts provided microhabitats with similar desiccation risks as microhabitats within forested drainages. I also determined survival of transmittered frogs that moved freely among microhabitats by radio-tracking 117 frogs over 3 years. I documented 29 predation events, 13 desiccation events, and 8 mortalities of unknown cause. Using Coxproportional hazard models, I found that survival within the timber harvest array was 1.7 times lower than survival within continuous forest. Survival was lowest during the drought year of 2005 when all desiccation events occurred. My results indicated that predation and desiccation risks near the breeding ponds are ecological pressures that explain why adult amphibians migrate away from breeding habitat during the nonbreeding season.

Download or read book Contributions of Behavior and Physiology to Conservation Biology written by Susan C. Walls and published by Frontiers Media SA. This book was released on 2020-03-30 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Natterjack Toad written by Trevor John Clark Beebee and published by . This book was released on 1983 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ecotoxicology of Amphibians and Reptiles written by Donald W. Sparling and published by CRC Press. This book was released on 2010-06-02 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: Building on the success of its popular predecessor, the second edition of Ecotoxicology of Amphibians and Reptiles presents newly available findings on the species that are important environmental indicators. This new edition covers nearly twice as many topics as the first, including recent developments in the ecotoxicology of amphibians and reptil

Download or read book Amphibian conservation action plan proceedings IUCN SSC Amphibian Conservation Summit 2005 written by and published by IUCN. This book was released on 2007 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Natural History of Amphibians written by Robert C. Stebbins and published by Princeton University Press. This book was released on 1997-01-26 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphibia, the animal group that includes frogs, toads, salamanders, and caecilians, contains more than 4,500 known living species and new ones are being discovered continuously. This book focuses on the natural history of amphibians worldwide, how interaction with their environment over time has affected their evolutionary processes and what factors will determine their destinies. 37 photos. 52 line illus.

Download or read book Experimental Studies of the Spatial Dynamics of T ngara Frog Populations written by David M. Marsh and published by . This book was released on 2000 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Amphibian Declines written by Michael J. Lannoo and published by Univ of California Press. This book was released on 2005-06-15 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Documents in comprehensive detail a major environmental crisis: rapidly declining amphibian populations and the disturbing developmental problems that are increasingly prevalent within many amphibian species.

Download or read book Climate Change and Ecological Models of Amphibian Communities in Palouse Prairie Wetlands written by Erim Gomez and published by . This book was released on 2020 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most wetlands in Palouse Prairie have been lost due to intensive agricultural development and amphibians now occupy a transformed landscape dominated by human use. I used machine learning statistical techniques to evaluate the performance of 30 environmental variables to predict the occurrence of 7 species of amphibians in 99 wetlands in Palouse Prairie and the Columbia River Basin of central Washington. Algorithmic models generally used about 3-5 ecological, landscape, or spatial variables to correctly predict amphibian occupancy in wetlands with high accuracy. These models demonstrate the adverse effects of non-native fish on pond-breeding amphibians and the importance of different wetland hydroperiods and ecological settings to influence amphibian breeding and conservation in novel human-dominated ecosystems.Ephemeral wetlands are productive for many breeding amphibian species partly because they dry up seasonally and are devoid of predatory fish. However, increasing temperatures and altered precipitation patterns that accompany global climate change may threaten these ecosystems if wetlands dry before amphibians can undergo metamorphosis. I studied growth dynamics of long-toed salamanders in Palouse Prairie wetlands to evaluate the hypothesis that growth was influenced by wetland periodicity and that salamander larva would be forced to emerge at a smaller body size in seasonally-flooded wetlands. I used machine learning modeling techniques to compare sizes of salamander larvae among different wetlands across time, elevation, and spatial landscapes in Palouse Prairie and found that size distributions were smaller in ephemeral ponds that dried more quickly and larger in more permanent wetlands. Salamanders originating from ephemeral wetlands were smaller as adults than were those coming from permanent wetlands suggesting a developmental penalty or genetic differences. If climate change alters the seasonal flooding dynamics of wetlands, it may influence population dynamics and survival of amphibians in Palouse Prairie wetlands.

Download or read book Behavioral Response of Adult and Larval Wood Frogs Lithobates Sylvaticus to a Common Road De icer NaCl written by Dylan Jones and published by . This book was released on 2018 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphibians are highly vulnerable to aquatic pollutants. Due to the permeability of their skin and their aquatic larval stages, pollutants are easily absorbed into the body, which can have adverse effects on performance, survival, and fitness. This has prompted research on how environmental pollutants affect amphibian populations, especially road deicers such as sodium chloride (NaCl). Elevated NaCl can have a negative physiological impact on both adult and larval stages of amphibians, leading to reduced breeding success, morphological abnormalities, and even mortality. However, less is known about the behavioral responses of adults and especially larval amphibians to increased environmental salinity. Earlier studies suggested that adult wood frogs did not show any behavioral responses to varying salinity with short-term (10 min) exposure, while larvae had not been assessed. In this study, the behavioral responses of both adult and larval wood frogs, Lithobates sylvaticus, to increased salinity were studied via salinity choice trials where a control (aged tap water) and a designated salt solution were placed on opposite sides of a binary arena for 3,600 seconds. Adults spent less time in NaCl solutions with increasing salinity. The threshold for response was approximately 0.17 M (slightly hyperosmotic to internal osmotic concentrations). For tadpoles, time spent in salt solutions did not change as salinity increased (to a maximum of 0.25 M NaCl), but these results were confounded by mixing between the control and the salt solutions. There were no behavioral differences in tadpole activity level (number of moves between chambers) as salinity increased. Since increased salinity has been associated with decreased fitness, behavioral avoidance of high salinity and preference for lower saline systems could be advantageous for wood frogs. Adults could potentially select breeding sites with lower solute levels that would be beneficial to egg masses and offspring. However, this study suggests that tadpoles in a high solute habitat may not change their activity level, potentially leading to inability to select microhabitats within a system. In addition, although adult wood frogs did respond to increasing salinity, they did so slower than previously assessed species, potentially making them more susceptible to habitat degradation. This study furthers the understanding of how amphibian populations respond to salinity influxes in the wild and will help to promote better conservation efforts for species vulnerable to salt pollution.

Download or read book Density dependence and Dispersal Mechanisms in a Pond Breeding Amphibian written by Katharine Yagi and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "In this thesis, I attempt to quantify the effect of density on toad dispersal in a series of steps that coincide with the amphibian's notable life stages, which are outlined by the five chapters of my thesis. Chapter 2 examines the direct effect of density on tadpole survival, growth and size at metamorphosis using a unique technique of density manipulation. I discuss potential downfalls of the traditional method of tadpole density-manipulations whereby raising them in crowded conditions might confound results as tadpoles are known to respond differently to chemical cues left in the water by conspecifics. My method of manipulating density by volume resulted in a strong negative relationship with tadpole survival, growth and size at metamorphosis, as predicted, while the traditional method showed similar but less striking trends. Chapter 3 addresses whether carry-over effects are present in the new metamorphs (i.e. toadlets) that emerge from a range of density treatments, by monitoring changes in behaviour between the tadpole and toadlet life stages. I discovered a significant change in activity levels in those grown under high densities as tadpoles, where their small post-metamorph body size coincided with a notable decrease in activity. My results support the concept of density-dependent carry-over effects being present in these amphibians, and that their post-metamorphic mobility may be impacted by their early-life growth conditions. Chapter 4 examines the behavioural plasticity of tadpoles under these effects using a controlled factorial experiment. My results showed that larger sized tadpoles had high activity levels under all temperature regimes only when they came from high density treatments. This suggests that the size of the animal is important, as it becomes relevant under more stressful conditions and that the behavioural plasticity of tadpoles is governed by an interaction among individual body size, water temperature and density. Chapter 5 follows the size-dependent movement capabilities of individual toadlets from density-treatments in a controlled performance test, and their subsequent free-ranging movement behaviour in the field. I discovered that the body size of toadlets predicted dispersal in a quadratic relationship, where intermediate sized toads, regardless of their tadpole density, move greater distances and had the highest probability for dispersal. Interestingly, these intermediate-sized toads became the largest in their cohort as adults, resulting in a positive logistic relationship between adult size and dispersal probability. Chapter 6 uses the information gathered for size-dependent dispersal probabilities, and calculates the populations density-dependent dispersal rates using historical data, to inform model simulations to predict the extinction risk of this Fowler's toad population. I discovered that this population has a quadratic relationship between dispersal probability and population density, where very low and very high densities coincided with the highest dispersal rates. Additionally, I was able to predict a low extinction risk for the population if carrying capacity was kept at a minimum of 16 toads, however if continuous habitat management, which translates into continuous habitat disturbances, were to be employed on a short 7-year cycle, extinction risk could be as high as 78%.Human activities, including fragmentation and restoration, continue to impact the animals living in the surrounding environment. As dispersal is a key process that can save many populations from local extinctions it is important to understand how movement is restricted on a species-specific level. My thesis provides a detailed examination of density-dependence and movement capabilities across multiple life stages in a pond breeding amphibian and advances our understanding of how density itself can impact dispersal under different mechanisms." --

Download or read book Amphibian Declines written by Michael Lannoo and published by Univ of California Press. This book was released on 2005-06-15 with total page 1117 pages. Available in PDF, EPUB and Kindle. Book excerpt: This benchmark volume documents in comprehensive detail a major environmental crisis: rapidly declining amphibian populations and the disturbing developmental problems that are increasingly prevalent within many amphibian species. Horror stories on this topic have been featured in the scientific and popular press over the past fifteen years, invariably asking what amphibian declines are telling us about the state of the environment. Are declines harbingers of devastated ecosystems or simply weird reflections of a peculiar amphibian world? This compendium—presenting new data, reviews of current literature, and comprehensive species accounts—reinforces what scientists have begun to suspect, that amphibians are a lens through which the state of the environment can be viewed more clearly. And, that the view is alarming and presages serious concerns for all life, including that of our own species. The first part of this work consists of more than fifty essays covering topics from the causes of declines to conservation, surveys and monitoring, and education. The second part consists of species accounts describing the life history and natural history of every known amphibian species in the United States.

Download or read book Science and Conservation of Vernal Pools in Northeastern North America written by Aram J. K. Calhoun and published by CRC Press. This book was released on 2007-08-13 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthesizes Decades of Research on Vernal Pools Science Pulling together information from a broad array of sources, Science and Conservation of Vernal Pools in Northeastern North America is a guide to the issues and solutions surrounding seasonal pools. Drawing on 15 years of experience, the editors have mined published literature,