A5013317039- Amphibian and Reptile Biology
- Species Distribution and Climate Change
- Wildlife Ecology and Conservation
- Rangeland and Wildlife Management
- Bat Biology and Ecology Studies
- Plant and animal studies
- Ecology and Vegetation Dynamics Studies
- Animal Behavior and Reproduction
- Turtle Biology and Conservation
- Ecology and biodiversity studies
- Environmental Toxicology and Ecotoxicology
- Animal and Plant Science Education
- Genetic diversity and population structure
- Insect and Pesticide Research
- Insect and Arachnid Ecology and Behavior
- Pharmaceutical and Antibiotic Environmental Impacts
- Environmental DNA in Biodiversity Studies
- Animal Vocal Communication and Behavior
- Marine animal studies overview
- Botany, Ecology, and Taxonomy Studies
- Pesticide and Herbicide Environmental Studies
- Avian ecology and behavior
- Animal Ecology and Behavior Studies
- Toxic Organic Pollutants Impact
- Wildlife-Road Interactions and Conservation
Western Ecological Research Center
2012-2023
United States Geological Survey
2011-2023
Center Point
2012-2023
Bear Valley
2011-2023
Marin Community Foundation
2018
United States Department of Agriculture
2013
Boston University
2010
Pacific Island Ecosystems Research Center
2007-2009
National Wildlife Health Center
2001
California Department of Parks and Recreation
1993
ABSTRACT Bats are hosts to a variety of viruses capable zoonotic transmissions. Because increased contact between bats, humans, and other animal species, the possibility exists for further cross-species transmissions ensuing disease outbreaks. We describe here full partial viral genomes identified using metagenomics in guano bats from California Texas. A total 34% 58% 390,000 sequence reads bat Texas, respectively, were related eukaryotic viruses, largest proportion those infect insects,...
Since amphibian declines were first proposed as a global phenomenon over quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for "smoking gun" was replaced with expectation that are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence effects of drivers is lacking at large spatial scales. Here, we use 389 time-series 83...
Abstract Several species of anuran amphibians have undergone drastic population declines in the western United States over last 10 to 15 years. In California, most severe are Sierra Mountains east Central Valley and downwind intensely agricultural San Joaquin Valley. contrast, coastal more northern populations across from less agrarian Sacramento stable or declining precipitously. this article, we provide evidence that pesticides instrumental these species. Using Hyla regilla as a sentinel...
There has been much concern about widespread declines among amphibians, but efforts to determine the extent and magnitude of these have hampered by scarcity comparative inventory data. We resurveyed a transect Sierra Nevada mountains in western North America that was carefully studied early 1900s. Our comparisons show at least five seven frog toad species area suffered serious declines. One disappeared from entirely second species, formerly most abundant amphibian area, dwindled few small...
Abstract Aricultural activity in California's Central Valley may be an important source of pesticides that are transported the air to Sierra Nevada Mountain Range, USA. Pesticides applied this intensive crop production area volatilize under warm temperatures typical valley and through atmosphere deposited cooler, higher elevation regions Mountains. To determine extent summertime atmospheric transport region, high-volume air, dry deposition, surface water samples were collected at different...
The chytrid fungus Batrachochytrium dendrobatidis was originally reported in wild frog populations Panama and Australia, from captive frogs the U.S. National Zoological Park (Washington, DC). This recently described affects keratinized epidermis of amphibians has been implicated as a causative factor declines populations. We report here presence B. larval metamorphosed mountain yellow-legged (Rana muscosa) or near Sierra Nevada Mountains California, an area where have documented all five...
Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate population losses. We conducted first analysis change in probability that amphibians occupy ponds and other comparable habitat features across United States. found overall occupancy by declined 3.7% annually from 2002 2011. Species Red-listed International Union for Conservation Nature (IUCN) an average 11.6% annually. All...
Significance Human influences are causing the disappearance of species at a rate unprecedented in millions years. Amphibians being particularly affected, and extinctions many may be inevitable. The Sierra Nevada yellow-legged frog ( Rana sierrae ) was once common mountains California (United States), but human impacts have driven it near extinction. Repeated surveys thousands water bodies Yosemite National Park show that decline R. has recently reversed population abundance is now increasing...
Contaminants have been associated with population declines of several amphibian species in California (USA). Pesticides from the Central Valley are transported by winds into Sierra Nevada Mountains and precipitate wet meadows where amphibians breed. The present study examined chronic toxicity two insecticides most commonly used found mountains, chlorpyrifos endosulfan, to larval Pacific treefrogs (Pseudacris regilla) foothill yellow-legged frogs (Rana boylii) discusses implications this...
Changing climate will impact species' ranges only when environmental variability directly impacts the demography of local populations. However, measurement demographic responses to change has largely been limited single species and locations. Here we show that amphibian communities are responsive climatic variability, using >500,000 time-series observations for 81 across 86 North American study areas. The effect on colonization persistence probabilities varies among eco-regions depends...
Comparative studies of mortality in the wild are necessary to understand evolution aging; yet, ectothermic tetrapods underrepresented this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study aging rates and longevity across tetrapod ectotherms, using data from 107 populations (77 species) nonavian reptiles amphibians. test hypotheses how thermoregulatory mode, environmental temperature, protective phenotypes, pace life history contribute...
Four species of myrmicine ants, Aphaenogaster rudis, A. treatae, tennesseensis, and fulva, use pieces leaf, mud, sand grains as tools to carry soft foods from distant sources the colony. Tools are tended on food removed by colony members without regard which individual brought tool. Food is gathered more efficiently tool than internal transport. Tool-using behavior may increase competitive ability rudis in an interspecific dominance hierarchy.
Abstract The pervasive and unabated nature of global amphibian declines suggests common demographic responses to a given driver, quantification major drivers could inform broad-scale conservation actions. We explored the influence climate on parameters (i.e., changes in probabilities survival recruitment) using 31 datasets from temperate zone populations (North America Europe) with more than decade observations each. There was evidence for an population rates, but direction magnitude highly...
We present a comprehensive survey of genetic variation across the range narrowly distributed endemic Yosemite toad Bufo canorus, declining amphibian restricted to Sierra Nevada California. Based on 322 bp mitochondrial cytochrome b sequence data, we found limited support for monophyly B. canorus and its closely related congener exsul exclusion widespread western boreas. However, was always phylogenetically nested within suggesting that latter may not be monophyletic. SSCP (single-strand...
In 1997, pesticide concentrations were measured in mountain yellow-legged frogs (Rana muscosa) from two areas the Sierra Nevada Mountains of California, USA. One area (Sixty Lakes Basin, Kings Canyon National Park) had large, apparently healthy populations frogs. A second (Tablelands, Sequoia once large populations, but species been extirpated this by early 1980s. The Tablelands is exposed directly to prevailing winds agricultural regions west. When an experimental reintroduction R. muscosa...
A population of individually marked Hyla versicolor was censused every night during the 1975 season to evaluate male breeding success. There no relationship between success and size or number nights a called. The data suggest that particular perch sites were especially advantageous calling places. Perches where males amplexed females surrounded by less vegetation which interfered with sound propagation mating call. distribution non-calling, subordinate is considered in relation dominant males.
Abstract Pesticides are receiving increasing attention as potential causes of amphibian declines, acting singly or in combination with other stressors, but limited information is available on the accumulation current‐use pesticides tissue. The authors examined exposure and currently used pond‐breeding frogs ( Pseudacris regilla ) collected from 7 high elevations sites northern California. All sampled located downwind California's highly agricultural Central Valley receive inputs through...
Abstract The red‐legged frog, Rana aurora , has been recognized as both a single, polytypic species and two distinct since its original description 150 years ago. It is currently one with geographically contiguous subspecies, draytonii ; the latter protected under US Endangered Species Act. We present results of survey 50 populations frogs from across their range plus four outgroup for variation in phylogenetically informative, ∼400 base pairs (bp) fragment mitochondrial cytochrome b gene....