Download or read book Contaminants as Contributing Factors to Wood Frog Abnormalities on the Kenai National Wildlife Refuge Alaska written by Mari Kathryn Reeves and published by . This book was released on 2008 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: Between 2004 and 2006 biologists assessed 38 breeding sites for prevalence of abnormal wood frogs in the Kenai National Wildlife Refuge. For 21 ponds variables known to cause abnormalities in amphibians were measured: ultraviolet-B radiation, temperature, water quality, contaminants, and abundance of predatory invertebrates. Of 5,716 metamorphic wood frogs examined, 450 had skeletal or eye abnomalities representing over 25 abnormality types. Intersex frogs were examined for abnormal gonadal morphology.
Download or read book Peril in the Ponds written by Judith Cairncross Helgen and published by Univ of Massachusetts Press. This book was released on 2012 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: When deformed frogs-many with missing legs or eyes, footless stumps, or misshapen jaws-began to emerge from Minnesota wetlands, alarm bells went off. What caused such deformities? Pollution? Ultraviolet rays? Biological agents? And could the mysterious cause also pose a threat to humans? Former government biologist Judy Helgen provides an inside view of a highly charged environmental issue that continues to spark controversy among scientists, politicians, and government agencies. Book jacket.
Download or read book Population Genetics and Metapopulation Structuring of the Wood Frog Rana Sylvatica in the Kenai National Wildlife Refuge Alaska written by Margaret K. Perdue and published by . This book was released on 2009 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multiple Stressors and the Cause of Amphibian Abnormalities written by Mary Kathryn Reeves and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of abnormal amphibians in nature points to ecological imbalance, yet identifying causes of these abnormalities has proven complex. Although multiple studies have linked amphibian abnormalities to chemically contaminated areas, inference about causal mechanisms is lacking. I investigated the relationship between multiple stressors and skeletal abnormalities in amphibians. My model system of metamorphic Alaskan wood frogs (Rana sylvatica) was simplified both by clear gradients in human disturbance lacking in other areas of the world and by relatively species-poor predator communities in the larval amphibian habitat. I conducted a series of studies progressing from field correlations to manipulative experiments to clarify the effects of multiple stressors in this system. First, I used road proximity as a proxy for human disturbance and tested relationships between skeletal abnormalities and anthropogenic influence in five National Wildlife Refuges in Alaska. This demonstrated that skeletal abnormalities were significantly correlated with proximity of the breeding site to the nearest road. I then used a high prevalence of abnormal frogs in one Alaskan Refuge (Kenai) to strengthen inference about the mechanisms for abnormalities by evaluating multiple putative causes of frog abnormalities at 21 wetlands. In this study, skeletal abnormalities were correlated with organic and inorganic contaminants and dragonfly predators. Manipulative experiments then evaluated the independent effects of each of these single-stressors. These studies showed that the abnormalities did not occur in high malformation sites when predators were excluded from the rearing environment. Furthermore, tadpoles reared in sediment and water from high malformation sites had lower hatching success, longer developmental periods and smaller size, but did not have skeletal abnormalities. Experimental amputation of the developing limbs of tadpoles resulted in malformations similar to those observed in the field. Together these observational and experimental results suggested that limb abnormalities were caused by a combination of multiple stressors. Specifically, toxicants led to increased predation, resulting in more injuries to developing limbs and subsequent developmental malformations. We used these investigations to generate the following ideas about how toxicants and predators may interact in nature. First, toxicant-induced activity reductions may reduce foraging, leading to smaller size and a longer time period during which tadpoles risk injurious predator encounters. Second, the ability of predators to injure, scare, or kill prey may be contingent on other factors, such as impaired behavior because of toxicants in the rearing environment. We devised an experiment to test whether a low concentration of copper would inhibit the ability of wood frog tadpoles to detect chemical cues of predators by olfactory means, causing them to respond inappropriately to predation risk. Contrary to expectations, we found that Cu, at an exposure level lower than any we could find reported as toxic to amphibians in the toxicology literature, did not affect predator detection but had strong effects on behavior, causing tadpoles to reduce activity and spend more time close to the water surface. When Cu and predator cues were administered together, the activity reduction was additive and stronger at earlier life stages. We argue that Cu intoxication would be disadvantageous to larval amphibian prey confronted by real predators, but this hypothesis should be tested with future work.
Download or read book Frogs and Toads of the Southeast written by Michael E. Dorcas and published by University of Georgia Press. This book was released on 2008 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive, authoritative, and fun-to-read identification guide enumerates the distinguishing characteristics of frogs and toads found throughout the southeastern United States and discusses their morphology, the main groups to be found in the Southeast, their habitats and distribution, life cycles, behavior, and conservation.
Download or read book Bears written by Christopher Servheen and published by IUCN. This book was released on 1999 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of the status of bear species by distribution / Christopher Servheen -- An overview of bear conservation planning and implementation / Bernard Peyton, Christopher Servheen, and Stephen Herrero -- Genetics of the bears of the world / Lisette Waits, David Paetkau, and Curtis Strobeck -- The trade in bears and bear parts / Christopher Servheen -- Brown bear conservation action plan for North America (Ursus arctos). Alaska / Sterling D. Miller and John Schoen. Canada / Bruce McLellan and Vivian Banci. United States: grizzly bear in the Lower 48 / Christopher Servheen -- Brown bear conservation action plan for Europe (Ursus arctos). Austria / Georg Rauer. Bulgaria / Nikolai Spassov and G. Spiridonov. Finland / Erik S. Nyholm and Kai-Eerik Nyholm. France / Jean Jacques Camarra. Greece / George Mertzanis. Italy (Abruzzo) / Giorgio Boscagli. Italy (Trentino) / Fabio Osti. Norway / Ole Jakob Sørensen, Jon E. Swenson, and Tor Kvam. Poland / Witold Frackowiak, Roman Gula, and Kajetan Perzanowski. Romania / Ovidiu Ionescu. Slovakia / Pavel Hell and Slavomir Find'o. Spain: eastern and western Cantabria. Eastern Cantabrian subpopulation / Anthony P. Clevenger and Francisco J. Purroy. Western Cantabrian subpopulation / Javier Naves Cienfuegos and Carlos Nores Quesada. Sweden / Jon E. Swenson, Finn Sandegren, Anders Bjärvall, Robert Franzén, Arne Söderberg, and Petter Wabakken. Former Yugoslavia / Djuro Huber and Miha Adamic -- Brown bear conservation action plan for Asia (Ursus arctos). China: Heilonjiang black and brown bears / Cheng Jizhen. India / S. Sathyakumar. Japan: Hokkaido / Tsutomu Mano and Joseph Moll. Mongolia: Gobi bear / Thomas McCarthy. Russia / Igor Chestin -- American black bear conservation action plan (Ursus americanus) / Michael R. Pelton, Alex B. Coley, Thomas H. Eason, Diana L. Doan Martinez, Joel A. Pederson, Frank T. van Manem and Keith M. Weaver -- Spectacled bear conservation action plan (Tremarctos ornatus) / Bernard Peyton. Bolivia / Damián I. Rumiz and Jorge Salazar. Colombia / Jorge Orejuela and Jeffrey P. Jorgenson. Ecuador / Luis Suárez. Perú / Bernard Peyton, coordinator. Venezuela / Edgard Yerena, coordinator -- Asiatic black bear conservation action plan (Ursus thibetanus). China / Ma Yiqing and Li Xiaomin. India / S. Sathyakumar. Japan / Toshihiro Hazumi. Russia / Igor Chestin and Victor Yudin. Taiwan: Formosan black bear / Ying Wang. Vietnam: black bear and sun bear / Do Dinh Sam -- Sun bear conservation action plan (Helarctos malayanus) / Christopher Servheen. Lao PDR / Richard E. Salter -- Sloth bear conservation action plan (Melursus ursinus) / David L. Garshelis, Anup R. Joshi, James L.D. Smith, and Clifford G. Rice -- Giant panda conservation action plan (Ailuropoda melanoleuca) / Donald G. Read and Jien Gong -- Global status and management of the polar bear (Ursus maritimus) / IUCN/SSC Polar Bear Specialist Group.
Download or read book Thermal Imaging Techniques to Survey and Monitor Animals in the Wild written by Kirk J Havens and published by Academic Press. This book was released on 2015-09-22 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal Imaging Techniques to Survey and Monitor Animals in the Wild: A Methodology provides a manual for anyone interested in understanding thermal imaging and its usefulness in solving a wide range of problems regarding the observation of wildlife. In the last decade, the cost of thermal imaging technology has significantly decreased, making the equipment more widely available. This book offers an overview of thermal physics and the thermal imager, along with a methodology to optimize the window of opportunity so that wildlife can be observed and studied in their natural habitat. Users will find the knowledge and tools to formulate a sound survey design, with detailed sections on the theory and performance characteristics of thermal imaging cameras utilizing cooled quantum detectors as the sensitive element and additional information on the uncooled micro bolometric imagers which have been introduced into the camera market in past decades. The methodology presented is logical and simple, yet it presents a detailed understanding of the topic and how it applies to the critically interlinked disciplines of biology, physics, micrometeorology, and animal physiology. - Covers the technical aspects of thermal imaging allowing readers to design better experiments - Provides a clear description of the properties of thermal imaging - Includes approaches to consider before integrating thermal cameras into a field
Download or read book Wilderness management written by John C. Hendee and published by . This book was released on 1978 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lichen Secondary Metabolites written by Branislav Ranković and published by Springer. This book was released on 2019-07-26 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: This revised and extended edition provides in-depth insights into the benefits and untapped potential of lichen-derived bioactive compounds. The whole spectrum of these compounds’ biological and medical functions, from antibiotic to antiviral and anti-carcinogenic properties, is presented. In addition, a new chapter discusses the anti-neurodegenerative and anti-diabetic activities of lichenic secondary metabolites. Given its scope, the book offers a valuable asset for students and researchers in this field.
Download or read book Machine Learning for Ecology and Sustainable Natural Resource Management written by Grant Humphries and published by Springer. This book was released on 2018-11-05 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecologists and natural resource managers are charged with making complex management decisions in the face of a rapidly changing environment resulting from climate change, energy development, urban sprawl, invasive species and globalization. Advances in Geographic Information System (GIS) technology, digitization, online data availability, historic legacy datasets, remote sensors and the ability to collect data on animal movements via satellite and GPS have given rise to large, highly complex datasets. These datasets could be utilized for making critical management decisions, but are often “messy” and difficult to interpret. Basic artificial intelligence algorithms (i.e., machine learning) are powerful tools that are shaping the world and must be taken advantage of in the life sciences. In ecology, machine learning algorithms are critical to helping resource managers synthesize information to better understand complex ecological systems. Machine Learning has a wide variety of powerful applications, with three general uses that are of particular interest to ecologists: (1) data exploration to gain system knowledge and generate new hypotheses, (2) predicting ecological patterns in space and time, and (3) pattern recognition for ecological sampling. Machine learning can be used to make predictive assessments even when relationships between variables are poorly understood. When traditional techniques fail to capture the relationship between variables, effective use of machine learning can unearth and capture previously unattainable insights into an ecosystem's complexity. Currently, many ecologists do not utilize machine learning as a part of the scientific process. This volume highlights how machine learning techniques can complement the traditional methodologies currently applied in this field.
Download or read book Wild Cats written by Kristin Nowell and published by World Conservation Union. This book was released on 1996 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the most comprehensive and up-to-date information available on the 36 wild cats of the world. It includes the first published collection of detailed range maps and some of the first photographs of rare species in the wild. It provides a thorough review of major issues in cat conservation such as habitat loss and management of big cats in livestock areas; field and laboratory research; international trade; the role of zoos; and reintroduction. High priority are identified to further the cause of cat conservation.
Download or read book Defending the Master Race written by Jonathan Spiro and published by UPNE. This book was released on 2009-12-15 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: A historical rediscovery of one of the heroic founders of the conservation movement who was also one of the most infamous racists in American history
Download or read book Timelines of Nearly Everything written by Manjunath.R and published by Manjunath.R. This book was released on 2021-07-03 with total page 2658 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book takes readers back and forth through time and makes the past accessible to all families, students and the general reader and is an unprecedented collection of a list of events in chronological order and a wealth of informative knowledge about the rise and fall of empires, major scientific breakthroughs, groundbreaking inventions, and monumental moments about everything that has ever happened.
Download or read book Canids written by Claudio Sillero-Zubiri and published by World Conservation Union. This book was released on 2004 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: The new Canid Action Plan synthesizes the current knowledge on the biology, ecology and status of all wild canid species, and outlines the conservation actions and projects needed to secure their long-term survival. Aiming at conservation biologists, ecologists, local conservation officials, administrators, educators, and all others dealing with canids in their jobs, the authors aspire to stimulate the conservation of all canids by highlighting problems, debating priorities and suggesting action.
Download or read book Under an Ionized Sky written by Elana Freeland and published by Feral House. This book was released on 2018-02-13 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is difficult to believe that our planet has been weaponized before our very eyes, but that is exactly what has happened. First, we were seduced by the convenience of a wireless world; then, atmospheric weather experimentation in the guise of carbons “climate change” converted the air we breathe into an antenna. Now, the geo-engineering we’ve been subjected to for two decades is being normalized as the “Star Wars” Space Fence rises around and within us. Is this the Space Age we were promised?
Download or read book National Water Summary 1988 89 written by and published by . This book was released on 1991 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability Index Models and Instream Flow Suitability Curves written by Richard L. Schroeder and published by . This book was released on 1985 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
