Download or read book Effects of Body Size on the Survival and Timing of Emigration of Newly Metamorphosed Northern Red legged Frogs written by Nathan D. Chelgren and published by . This book was released on 2003 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to investigate the survival and movements of newly metamorphosed Northern Red-legged frogs (Rana aurora aurora) as they emigrated from two ephemeral breeding ponds. Quantifying survival and movement rates will be important to our understanding how changes to terrestrial and aquatic systems affect behavior and population dynamics. I manipulated food availability for a subset of uniquely marked metamorphic frogs and then analyzed temporal and spatial aspects of their recapture in forest pitfall traps relative to body size and date of metamorphosis. The probability of surviving and emigrating increased strongly with increasing body size and declined for frogs metamorphosing later in the season. Larger body size was associated with earlier emigration and greater correlation of movements with rainfall events. Within a pond, the time elapsed between metamorphosis and emigration was not affected by the pond drying. My results demonstrate that conditions during the tadpole stage which affect body size and the timing of metamorphosis may have a dramatic impact on the performance of frogs during their initial transition into the terrestrial environment.
Download or read book Effects of Multiple Stressors written by Lindsey L. Gordon and published by . This book was released on 2020 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: As human activities reach every corner of the globe, climate change, invasive species, habitat destruction, and other stressors causing species’ declines no longer act alone. Climate change has the potential to exacerbate (or mitigate) other stressors (e.g. invasive species or pathogens) affecting amphibian populations. I assessed the combined effects of increased pond drying rates (potential impact of climate change), invasive bullfrogs (Lithobates catesbeianus) presence, and food availability on northern red-legged frog (Rana aurora) survival and body size after metamorphosis by rearing tadpoles under incrementally shortened hydroperiods with and without the presence of invasive bullfrog tadpoles in low and high food environments. To explore the underlying mechanisms driving the impact of bullfrogs on R. aurora tadpoles, I had two treatments where bullfrog tadpoles were either separated by a permeable barrier (behavioral cue) or free to move about the tanks (direct competition/predation). To validate the captive experiment, I examined the influence of hydroperiod length on R. aurora survival, development, and growth in a field-based mesocosm experiment. I found hydroperiod to have a threshold effect on survival through metamorphosis in the captive experiment. Once the hydroperiod threshold was met in both the captive and field study, I found no benefit of longer hydroperiods on survival through metamorphosis. Drying rate influenced R. aurora developmental rates, but the effects were dependent on life stage and time of season in the field study. Size at metamorphosis was synergistically affected by bullfrog presence and food availability in the captive experiment. Tadpoles emerged as smaller metamorphs when exposed to bullfrogs in a low food environment. In the field experiment, size at metamorphosis was positively affected by longer hydroperiod and later emergence date. Understanding how multiple stressors impact larval growth and survival is an important component for managing and potentially mitigating the interactive effects of climate change and invasive species for amphibian conservation.
Download or read book The Influence of Canopy Cover and Climate on Early Life stage Vital Rates for Northern Red legged Frogs Rana Aurora and the Implications for Population Growth Rates written by Kecly W. McHarry and published by . This book was released on 2017 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily relatable to the effects of climate change and collected at fine scales without specialized equipment. Estimates from field data, along with published accounts were used in a matrix modeling analysis to evaluate if tadpole survival impacted population growth rates. Egg hatch success did not differ between canopy treatments or among sites. Canopy cover did affect tadpole survival rates, but not tadpole development time. The effect of canopy over on tadpole survival varied depending on which population was being evaluated. There was no evidence that the effect of canopy cover on tadpole survival was dependent on air temperature. Tadpole survival rates did impact population growth rates. This research shows that the effect of canopy cover on early stage vital rates for this species is variable between populations, but not due to differences in average air temperatures. For some populations the effect of canopy cover on tadpole survival was large enough to change projected population growth rates from stable to decreases of 30%. These results demonstrate that manipulating canopy cover can influence tadpole survival sufficiently enough to alter population trajectories. However, the variable effects of canopy cover on vital rates suggest a universal management strategy through canopy cover manipulation will not have equal impacts across populations.
Download or read book Canadian Journal of Zoology written by and published by . This book was released on 2008-04 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conservation of California Red legged Frogs written by Antonia J. D'Amore and published by . This book was released on 2007 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book COSEWIC Assessment and Update Status Report on the Red legged Frog Rana Aurora in Canada electronic Resource written by Committee on the Status of Endangered Wildlife in Canada and published by COSEWIC Secretariat, Canadian Wildlife Service. This book was released on 2004 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The red-legged frog is one of the six species of true frogs native to North America, an inhabitant of moist, lower elevation forests. In Canada, it is found on Vancouver Island, on several Strait of Georgia islands, and on the adjacent mainland. This report provides an assessment of the status of this species. It includes information on its classification, physical characteristics, geographic distribution, habitat, biology (reproduction, survival, predators, physiology, movements, dispersal, nutrition, behaviour, adaptability), population sizes & trends, the factors & threats limiting the population, the special significance of the species, and existing protection or other status of the species.
Download or read book Ecological Effects of Climate Change on Amphibians written by Hilary Byrne Rollins and published by . This book was released on 2019 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: With climate change, global average temperatures are increasing and becoming more variable. As a result, reproductive phenology is shifting earlier, body size is decreasing in ectotherms, and snow cover is decreasing. I examined how these effects of climate change affected amphibians and their ecological interactions across life stages. In Chapter 1, I investigated whether an early shift in phenology could alter subsequent life history events, if the organisms were able to compensate, and if compensation was costly. Despite a seven day difference in hatch date, frogs from the delayed egg phenology treatment accelerated growth and development to metamorphose at the same time as the early egg phenology treatment. Frogs that accelerated development metamorphosed at the same size as frogs that did not accelerate development but had the same food availability, indicating that there was no size cost of compensation. In Chapter 2, to understand how climate change-induced shifts in phenotype could affect important interspecific interactions, I examined how a shift in wood frog larval phenology, and body size altered post-metamorphic competition with American toads. The interaction of wood frog metamorphic size and phenology affected toad body condition such that wood frogs that metamorphosed earlier and smaller, as expected under climate change, led to toads with higher body condition.Finally, in Chapter 3, I tested whether the effects of climate change on wood frogs were altered by early ecological interactions. I examined how predation during larval development affected how wood frogs would tolerate a reduced snow cover winter. Exposure to predators during larval development increased mass at metamorphosis, time to metamorphosis, and larval growth rate. Snow removal increased frog mortality. The interaction of larval exposure to predators and reduced snow cover caused a steeper relationship between mass and body length in animals that experienced both. I found that the ecological effects of climate change shifted larval development and juvenile growth, reduced the ability to compete against interspecific competitors, increased winter mortality, and altered spring body condition. These effects may scale up to affect population dynamics and fitness, and demonstrate the importance of considering ecological effects of climate change.
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 Wildlife Disease Ecology written by Kenneth Wilson and published by Cambridge University Press. This book was released on 2019-11-14 with total page 693 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduces readers to key case studies that illustrate how theory and data can be integrated to understand wildlife disease ecology.
Download or read book A Synopsis of the Amphibia of California written by Tracy Irwin Storer and published by . This book was released on 1925 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Amphibian Conservation written by Rebecca K. Smith and published by Pelagic Publishing Ltd. This book was released on 2014-05-16 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphibian Conservation is the fourth in the series of Synopses of Conservation Evidence, linked to the online resource www.ConservationEvidence.com. This synopsis is part of the Conservation Evidence project and provides a useful resource for conservationists. It forms part of a series designed to promote a more evidence-based approach to biodiversity conservation. Others in the series include bee, bird, farmland and bat conservation and many others are in preparation. Approximately 32% of the 7,164+ amphibian species are currently threatened with extinction and at least 43% of species are declining. Despite this, until recently amphibians and their conservation had received little attention. Although work is now being carried out to conserve many species, often it is not adequately documented. This book brings together and summarises the available scientific evidence and experience relevant to the practical conservation of amphibians. The authors consulted an international group of amphibian experts and conservationists to produce a thorough summary of what is known, or not known, about the effectiveness of amphibian conservation actions across the world. "The book is packed with literature summaries and citations; a veritable information goldmine for graduate students and researchers. It also admirably provides decision makers with a well-researched resource of proven interventions that can be employed to stem/reverse the decline of amphibian populations." -John G Palis, Bulletin of the Chicago Herpetological Society
Download or read book Everything You Need to Know About Frogs and Other Slippery Creatures written by DK and published by Penguin. This book was released on 2011-07-18 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Everything You Need to Know About Frogs and Other Slippery Creatures is a fascinating read - not only do you discover the basics of reptile and amphibian anatomy, you also learn about the lives and times of a great number of creatures: see how they survive in lakes and rivers, forests and deserts, and how they have adapted to the most inhospitable habitats. Everything You Need to Know About Frogs and Other Slippery Creatures provides ideas for things to make, games to play, quizzes, and shocking facts to share with your friends. It's everything you need to know, and everything you WANT to find out.
Download or read book Riparian Management Area Guidebook written by BC Environment and published by Forest Service British Columbia. This book was released on 1995-01-01 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Helps managers, planners and field staff set and comply with Forest Practices Code standards for management of riparian management areas (RMAs).
Download or read book Ranaviruses written by Matthew J. Gray and published by Springer. This book was released on 2015-05-01 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book on ranaviruses. Ranaviruses are double-stranded DNA viruses that cause hemorrhagic disease in amphibians, reptiles, and fish. They have caused mass die-offs of ectothermic vertebrates in wild and captive populations around the globe. There is evidence that this pathogen is emerging and responsible for population declines in certain locations. Considering that amphibians and freshwater turtles are suitable hosts and the most imperiled vertebrate taxa in the world, ranaviruses can have significant impacts on biodiversity and ecosystem function. Additionally, many fish that are raised in aquaculture facilities and traded internationally are suitable hosts; thus, the potential economic impact of ranaviruses is significant. Ranaviruses also serve as a model for replication and gene function of large double-stranded DNA viruses. There is an urgent need to assemble the contemporary information on ranaviruses and provide guidance on how to assess their threats in populations. Through the Global Ranavirus Consortium, 24 experts from six countries were organize to write this volume, the first book on ranaviruses. The book begins with a discussion on the global extent of ranaviruses, case histories of infection and disease in ectothermic vertebrates, and current phylogeny. Basic principles of ranavirus ecology and evolution are covered next, with a focus on host-pathogen interactions and how the virus emerges in its environment. There are two chapters that will discuss the molecular biology of ranaviruses, host response to infection, and the genes responsible for immune system evasion. One chapter establishes standards for testing for infection and diagnosing ranaviral disease. The book ends by providing guidance on how to design ranavirus surveillance studies and analyze data to determine risk, and discussing the role of the Global Ranavirus Consortium in organizing research and outreach activities.
Download or read book The Biology of Chameleons written by Krystal A. Tolley and published by Univ of California Press. This book was released on 2013-11-16 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: They change color depending on their mood. They possess uniquely adapted hands and feet distinct from other tetrapods. They feature independently movable eyes. This comprehensive volume delves into these fascinating details and thorough research about one of the most charismatic families of reptilesÑChameleonidae. Written for professional herpetologists, scholars, researchers, and students, this book takes readers on a voyage across time to discover everything that is known about chameleon biology: anatomy, physiology, adaptations, ecology, behavior, biogeography, phylogeny, classification, and conservation. A description of the natural history of chameleons is given, along with the fossil record and typical characteristics of each genus. The state of chameleons in the modern world is also depicted, complete with new information on the most serious threats to these remarkable reptiles.
Download or read book Threatened Amphibians of the World written by S. N. Stuart and published by . This book was released on 2008 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Amphibians are facing an extinction crisis, but getting to the facts has been difficult. "Threatened Amphibians of the World" is a visual journey through the first-ever comprehensive assessment of the conservation status of the world's 6,000 known species of frogs, toads, salamanders, and caecilians. All 1,900 species known to be threatened with extinction are covered, including a description of threats to each species and an evaluation of conservation measures in place or needed. Each entry includes a photograph or illustration of the species where available, a distribution map, and detailed information on range, population and habitat and ecology. Introductory chapters present a detailed analysis of the results, complemented by a series of short essays written by many of the world's leading herpetologists. Appendices include annoted lists of lower risk species and a country-by-country listing of threatened amphibians."--pub. desc.
Download or read book Real Gardens Grow Natives written by Eileen M Stark and published by Mountaineers Books. This book was released on 2014-09-24 with total page 645 pages. Available in PDF, EPUB and Kindle. Book excerpt: CLICK HERE to download sample native plants from Real Gardens Grow Natives For many people, the most tangible and beneficial impact they can have on the environment is right in their own yard. Aimed at beginning and veteran gardeners alike, Real Gardens Grow Natives is a stunningly photographed guide that helps readers plan, implement, and sustain a retreat at home that reflects the natural world. Gardening with native plants that naturally belong and thrive in the Pacific Northwest’s climate and soil not only nurtures biodiversity, but provides a quintessential Northwest character and beauty to yard and neighborhood! For gardeners and conservationists who lack the time to read through lengthy design books and plant lists or can’t afford a landscape designer, Real Gardens Grow Natives is accessible yet comprehensive and provides the inspiration and clear instruction needed to create and sustain beautiful, functional, and undemanding gardens. With expert knowledge from professional landscape designer Eileen M. Stark, Real Gardens Grow Natives includes: * Detailed profiles of 100 select native plants for the Pacific Northwest west of the Cascades, plus related species, helping make plant choice and placement. * Straightfoward methods to enhance or restore habitat and increase biodiversity * Landscape design guidance for various-sized yards, including sample plans * Ways to integrate natives, edibles, and nonnative ornamentals within your garden * Specific planting procedures and secrets to healthy soil * Techniques for propagating your own native plants * Advice for easy, maintenance using organic methods
