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The dynamic geological and climatic history of northwestern North America has made it a focal region for phylogeography. We conducted a range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) across its range in northwestern North America to understand its evolutionary history and the distribution of clades to inform conservation of R. pretiosa and Great Basin R. luteiventris, candidates for listing under the US Endangered Species Act. Mitochondrial DNA sequence data from a segment of the cytochrome b gene were obtained from 308 R. luteiventris and R. pretiosa from 96 sites. Phylogenetic analysis revealed one main R. pretiosa clade and three main R. luteiventris clades,...
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The repeated occurrence of abnormal amphibians in nature points to ecological imbalance, yet identifying causes of these abnormalities has proved complex. Multiple studies have linked amphibian abnormalities to chemically contaminated areas, but inference about causal mechanisms is lacking. Here we use a high incidence of abnormalities in Alaskan wood frogs to strengthen inference about the mechanism for these abnormalities. We suggest that limb abnormalities are caused by a combination of multiple stressors. Specifically, toxicants lead to increased predation, resulting in more injuries to developing limbs and subsequent developmental malformations. We evaluated a variety of putative causes of frog abnormalities...
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Five species of amphibians, all anurans, are known to occur in the Northwest Territories (NT): wood frogs (Rana sylvatica = Lithobates sylvaticus; Family Ranidae), northern leopard frogs (Rana pipiens = Lithobates pipiens; Family Ranidae), western toads (Bufo boreas = Anaxyrus boreas; Family Bufonidae), Canadian toads (Bufo hemiophrys = Anaxyrus hemiophrys; Famiily Bufonidae) and boreal chorus frogs (Pseudacris maculata; Family Hylidae). Of these five, wood frogs, western toads, and boreal chorus frogs, are known from the Dehcho whereas wood frogs and boreal chorus frogs are known from the Sahtu. Baseline information on species distribution and abundance is key to identifying and then addressing declines...
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A statewide database and GIS has been created for amphibian observations in the National Parks of Alaska. This database contains the records for an opportunistic survey of 2001-2003.
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Four amphibian species occur in the Yukon: Western Toad (Bufo boreas; first verified record in 1961), the Boreal Chorus Frog (Pseudacris maculata, first record in 1995), the Columbia Spotted Frog (Ram luteiventris, first record in 1993), and the Wood Frog (Rana sylvatica; first record in 1933). The Western Toad is restricted to the Liard Basin in five geographically separated areas. Breeding sites have been located on the lower Coal River and vicinity. The Boreal Chorus Frog has been documented from a small area of the lower La Biche River valley near the Yukon-British Columbia-Northwest Territories border. The Columbia Spotted Frog occurs in two widely separated areas, at Bennett Lake in the southwest and in the...
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Amphibians with missing, misshapen, and extra limbs have garnered public and scientific attention for two decades, yet the extent of the phenomenon remains poorly understood. Despite progress in identifying the causes of abnormalities in some regions, a lack of knowledge about their broader spatial distribution and temporal dynamics has hindered efforts to understand their implications for amphibian population declines and environmental quality. To address this data gap, we conducted a nationwide, 10-year assessment of 62,947 amphibians on U.S. National Wildlife Refuges. Analysis of a core dataset of 48,081 individuals revealed that consistent with expected background frequencies, an average of 2% were abnormal,...
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The National Park Service, Southeast Alaska Network (SEAN), identified amphibians as a taxonomic group of concern at the Biological Inventory Scoping Meeting in April 2000, because distribution, status and habitat requirements are poorly understood in Alaska for most species. In order to begin to understand basic distribution and species survival, an opportunistic amphibian inventory was developed for 2001-03 by the Inventory & Monitoring Program. In all, 78 observations were recorded in 10 of the 16 National Parks of Alaska, finding approximately 1600 amphibians in three years. Species found included western toad Bufo boreas, wood frog Rana sylvatica, Columbian spotted frog R. luteiventris, and surprisingly, a...


    map background search result map search result map Multiple stressors and the cause of amphibian abnormalities Twice as easy to catch? A toxicant and a predator cue cause additive reductions in larval amphibian activity Western toad, Bufo boreas, stewardship in the Yukon: Yukon biodiversity report Occurrence of Amphibians in British Columbia North of 57°N Diversity and Range of Amphibians of the Yukon Territory Atlin Lake Terrestrial Environment Baseline Studies - 2010 Amphibian Surveys. Prepared for: Yukon Energy Corporation and AECOM Canada Ltd National malformed amphibian study, FY2000: Kenai National Wildlife Refuge, Annual Progress Report Range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) in northwestern North America Southern Lakes Terrestrial Environment Baseline Studies - 2010 Amphibian Surveys. Prepared for: Yukon Energy Corporation and AECOM Canada Ltd Alaska Parks Amphibian Inventory 2003 Version An opportunistic amphibian inventory in Alaska's national parks 2001-2003. Final Report Wood Frog (Rana sylvatica) Survey Results: Chitina to McCarthy Road Wood Frog Surveys 2002 Amphibian population and pathogen surveys in the Dehcho and Sahtu, Northwest Territories, 2007 and 2008 Southern Lakes Terrestrial Environment Baseline Studies - 2010 Amphibian Surveys. Prepared for: Yukon Energy Corporation and AECOM Canada Ltd Multiple stressors and the cause of amphibian abnormalities Twice as easy to catch? A toxicant and a predator cue cause additive reductions in larval amphibian activity National malformed amphibian study, FY2000: Kenai National Wildlife Refuge, Annual Progress Report Range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) in northwestern North America Wood Frog (Rana sylvatica) Survey Results: Chitina to McCarthy Road Wood Frog Surveys 2002 Occurrence of Amphibians in British Columbia North of 57°N Atlin Lake Terrestrial Environment Baseline Studies - 2010 Amphibian Surveys. Prepared for: Yukon Energy Corporation and AECOM Canada Ltd Amphibian population and pathogen surveys in the Dehcho and Sahtu, Northwest Territories, 2007 and 2008 Diversity and Range of Amphibians of the Yukon Territory Western toad, Bufo boreas, stewardship in the Yukon: Yukon biodiversity report Alaska Parks Amphibian Inventory 2003 Version An opportunistic amphibian inventory in Alaska's national parks 2001-2003. Final Report