|Scientific Name:||Ascaphus truei|
|Species Authority:||Stejneger, 1899|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Geoffrey Hammerson, Michael Adams|
|Reviewer(s):||Global Amphibian Assessment Coordinating Team (Simon Stuart, Janice Chanson, Neil Cox and Bruce Young)|
Listed as Least Concern in view of its wide distribution, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.
|Range Description:||This species ranges from the Cascades and the Pacific Coast from southern British Columbia, Canada south to north-western California, USA (Stebbins 1985, Nielson et al. 2001).|
Native:Canada; United States
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This species has many extant occurrences distributed throughout the range. Total population size is unknown but probably exceeds 10,000. It is common in suitable habitat. Its long-term trend is likely relatively stable in terms of extent of occurrence. There has been an unknown degree of decline in population size, area of occupancy, and number/condition of locations. Its short-term population trend is probably declining based on habitat trends, but few population data are available.|
|Habitat and Ecology:||Can be found in clear, cold swift-moving mountain streams with coarse substrates. Primarily in older forest sites, required microclimatic and microhabitat conditions are more common in older forests (Welsh 1990). Diller and Wallace (1999) reported that canopy cover, temperature, and forest age in managed forests were not significantly different between occupied and unoccupied stream reaches in northern California; however, this probably reflects past timber harvest patterns. Animals may be found on land during wet weather near water in humid forests or in more open habitat. During dry weather it stays on moist stream-banks and lays eggs in long strings under stones in water.|
|Major Threat(s):||It is sensitive to logging and road building (Leonard et al. 1993). Logging and construction practices that increase water temperatures and siltation might have an adverse effect on tailed frog populations (Nussbaum et al. 1983, Welsh and Ollivier 1998). See also Bury and Corn (1988) and Corn and Bury (1989) for information on negative effects of timber harvest. Diller and Wallace (1999) emphasized that current timber harvest practices are not as detrimental as those used in the past. Despite negative effects of logging, this species frequently occurs in many young forests that have been harvested one or more times in the past. Sensitivity to timber harvest might depend on surface geology and harvest practices (Adams and Bury 2002, Welsh and Lind 2002).|
|Conservation Actions:||Range includes many national parks and wilderness areas. Maintenance of cool, forested, unsilted streams and stream corridors is a basic conservation need.|
Adams, M.J. and Bury, R.B. 2002. The endemic headwater stream amphibians of the American Northwest: associations with environmental gradients in a large forested preserve. Global Ecology and Biogeography: 169-178.
Behler, J.L. and King, F.W. 1979. The Audubon Society Field Guide to North American Reptiles and Amphibians. New York.
Blackburn, L., Nanjappa, P. and Lannoo, M.J. 2001. An Atlas of the Distribution of U.S. Amphibians. Ball State University, Muncie, IN, USA.
Bury, R.B. and Adams, M.J. 1999. Variation in age at metamorphosis across a latitudinal gradient for the tailed frog, Ascaphus truei. Herpetologica: 283-291.
Bury, R.B. and Corn, P.S. 1988. Responses of aquatic and streamside amphibians to timber harvest: a review. In: Raedaeke, K. (ed.), Streamside management: riparian wildlife and forestry interactions, pp. 165-181. Univ. Washington.
Corn, P.S. and Bury, R.B. 1989. Logging in western Oregon: responses of headwater habitats and stream amphibians. Forest Ecology and Management: 39-57.
Daugherty, C.H. and Sheldon, A.L. 1982. Age-determination, growth, and life history of a Montana population of the tailed frog (Ascaphus truei). Herpetologica: 461-468.
Daugherty, C.H. and Sheldon, A.L. 1982. Age-specific movement patterns of the frog Ascaphus truei. Herpetologica: 468-474.
Diller, L.V. and Wallace, R.L. 1999. Distribution and habitat of Ascaphus truei in streams in managed, young growth forests in north coastal California. Journal of Herpetology: 71-79.
Dupuis, L. 1998. Status report on the tailed frog, Ascaphus truei, in Canada (draft). Unpublished draft report submitted to the Commitee on the Status of Endangered Wildlife in Canada, Ottawa.
Dvornich, K.M., McAllister, K.R. and Aubry, K.B. 1997. Amphibians and reptiles of Washington State: Location data and predicted distributions, Vol. 2. In: Cassidy, K.M., Grue, C.E., Smith, M.R. and Dvornich, K.M. (eds), Washington State Gap Analysis - Final Report, Washington Cooperative Fish and Wildlife Research Unit, University of Washington, Seattle, Washington.
IUCN. 2004. 2004 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 23 November 2004.
Leonard, W.P., Brown, H.A., Jones, L.L.C., McAllister, K.R. and Storm, R.M. 1993. Amphibians of Washington and Oregon. Seattle Audubon Society, Seattle, Washington.
Metter, D. and Pauken, R. 1969. An analysis of the reduction of gene flow in Ascaphus truei in the northwest U.S. since the Pleistocene. Copeia: 301-307.
Metter, D.E. 1968. Ascaphus and A. truei. Catalogue of American Amphibians and Reptiles: 1-2.
Nielson, M., Lohman, K. and Sullivan, J. 2001. Phylogeography of the tailed frog (Ascaphus truei): implications for the biogeography of the Pacific Northwest. Evolution: 147-160.
Nussbaum, R.A., Brodie, Jr., E.D. and Storm, R.M. 1983. Amphibians and Reptiles of the Pacific Northwest. University Press of Idaho, Moscow, ID, USA.
Ritland, K., Dupuis, L.A., Bunnell, F.L., Hung, W.L.Y. and Carlson, J.E. 2000. Phylogeography of the tailed frog (Ascaphus truei) in British Columbia. Canadian Journal of Zoology: 1749-1758.
Species at Risk Branch. 2002. Species at Risk Range Maps. Canadian Wildlife Service, Environment Canada. (http://www.sis.ec.gc.ca/download_e.htm), Ottawa.
Stebbins, R.C. 1985. A Field Guide to Western Reptiles and Amphibians. Second Edition. Houghton Mifflin Company, Boston, Massachusetts.
Stebbins, R.C. 2003. A Field Guide to Western Reptiles and Amphibians, Third Edition. Houghton Mifflin Company, Boston, Massachusetts.
Thomas, J.W., Ward, J., Raphael, M.G., Anthony, R.G., Forsman, E.D., Gunderson, A.G., Holthausen, R.S., Marcot, B.G., Reeves, G.H., Sedell, J.R. and Solis, D.M. 1993. Viability assessments and management considerations for species associated with late-successional and old-growth forests of the Pacific Northwest. The report of the Scientific Analysis Team. USDA Forest Service, Spotted Owl EIS Team, pp. 530 pp. Portland, Oregon.
Wallace, R.L. and Diller, L.V. 1998. Length of the larval cycle of Ascaphus truei in coastal streams of the redwood region, northern California. Journal of Herpetology: 404-409.
Welsh, H.H., Jr. 1990. Relictual amphibians and old-growth forests. Conservation Biology: 309-319.
Welsh, H.H., Jr. and Lind, A.J. 2002. Multiscale habitat relationships of stream amphibians in the Klamath-Siskiyou region of California and Oregon. Journal of Wildlife Management: 581-602.
Welsh, H.H., Jr., Hodgson, G.R. and Lind, A.J. 2005. Ecogeography of the herpetofauna of a northern Californian watershed: linking species patterns to landscape processes. Ecography: 521-536.
|Citation:||Geoffrey Hammerson, Michael Adams 2004. Ascaphus truei. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 02 October 2014.|