Description
A large, usually aquatic salamander. Most individuals never metamorphose and retain gills throughout life. Only six metamorphosed individuals have been found in the wild (Nussbaum 1976; Loafman and Jones 1996), and description here applies primarily to the larval form. Adults reach 6.5 - 11.4 cm snout to vent length and can be up to 20.5 cm total length (Nussbaum 1983; Leonard et al. 1993).

The dorsum is brown with little mottling, often with yellowish tan patches. The venter of young individuals is white and in older individuals it is bluish gray. The morphology is typical of stream-dwelling larval salamanders with short, bushy gills and a low tail fin that extends onto the body, forward of the hind limb insertion. Eyes are lidless (Petranka 1998).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: United States

U.S. state distribution from AmphibiaWeb's database: Oregon, Washington

View distribution map in BerkeleyMapper.

Distributed in the Coast Ranges of the Olympic Peninsula, Washington, to just south of the Columbia River in northwestern Oregon. Also found in the Cascade Mountains of northern Oregon and southern Washington (Nussbaum 1983; Petranka 1998).

Dicamptodon copei inhabit cold, fast-flowing streams in humid, coniferous forests. Individuals may be found under rocks and woody debris (Petranka 1998).

Life History, Abundance, Activity, and Special Behaviors
Mating and courtship have not been described. Dicamptodon copei is likely to be similar to other species of Dicamptodon (Petranka 1998). Eggs are laid throughout the year, but primarily in the winter months. Nests sites are on the undersides of rocks or other cover. Females attend the eggs until hatching, and will aggressively defend against conspecific predators. Clutch size ranges from 25 - 115, average about 50 (Nussbaum et al. 1983).

Dicamptodon copei feed on a variety of aquatic invertebrates and also small fish (trout and sculpin), eggs and tadpoles of tailed frogs (Ascaphus), and smaller larval Dicamptodon (Nussbaum et al. 1983). Predators are garter snakes (Thamnophis), water shrews (Sorex palustris), and D. tenebrosus (Nussbaum 1970; Nussbaum et al. 1983; Loafman and Jones 1996). Larvae may emerge from streams on particularly wet nights (Nussbaum et al. 1983)

Larva
Cope's Giant Salamander is nearly an obligate paedomorphic species, and its gilled aquatic form is retained when it sexually matures..

Trends and Threats
Logging is a threat to populations of D. copei both through direct destruction of habitat and also through increased siltation of streams (Petranka 1998).

Comments
For a long time, D. copei was not distinguished from D. ensatus (Nussbaum 1970; 1976; 1983). Recent genetic studies (Dougherty et al. 1983; Good 1989) have supported the recognition of these forms as separate species. The genus Dicamptodon was historically included as a subfamily (Dicamptodontinae) in the family Ambystomatidae, and was placed in a separate family, Dicamptodontidae, based on features of the spinal nerves (Edwards 1976).

References

Daugherty, C. H., Allendorf, F. W., Dunlap, W. W., and Knudsen, K. L. (1983). ''Systematic implications of geographic patterns of genetic variation in the genus Dicamptodon.'' Copeia, 1983(3), 679-691.

Edwards, J.L. (1976). "Spinal nerves and their bearing on salamander phylogeny." Journal of Morphology, 148, 305-328.

Good, D.A. (1989). "Hybridization and cryptic species in Dicamptodon (Caudata: Dicamptodontidae)." Evolution, 43, 728-744.

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, Seattle.

Loafman, P., and Jones, L. (1996). ''Dicamptodon copei (Cope's Giant Salamander). Metamorphosis and predation.'' Herpetological Review, 27, 136.

Nussbaum, R. A. (1970). "Dicamptodon copei, n. sp., from the Pacific Northwest, U.S.A. (Amphibia: Caudata: Ambystomatidae)." Copeia, 1970, 506-514.

Nussbaum, R. A. (1976). "Geographic variation and systematics of salamanders of the genus Dicamptodon Strauch (Ambystomatidae)." Miscellaneous Publications of the Museum of Zoology, University of Michigan, 149, 1-94.

Nussbaum, R. A. (1983). ''Dicamptodon copei Nussbaum. Cope's Giant Salamander.'' Catalogue of American Amphibians and Reptiles. Society for the Study of Amphibians and Reptiles, 334.1-334.2.

Nussbaum, R. A., Brodie, E. D., Jr., and Storm, R. M. (1983). Amphibians and Reptiles of the Pacific Northwest. University of Idaho Press, Moscow, Idaho.

Petranka, J. W. (1998). Salamanders of the United States and Canada. Smithsonian Institution Press, Washington D.C. and London.

Species Account Citation: AmphibiaWeb 2022 Dicamptodon copei: Cope's Giant Salamander <https://amphibiaweb.org/species/3865> University of California, Berkeley, CA, USA. Accessed Nov 26, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 26 Nov 2024.

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