Pacific Giant Salamanders: Dicamptodontidae
Coastal Giant Salamander (dicamptodon Tenebrosus): Species Account
Physical characteristics: Adult coastal giant salamanders may be the largest land-dwelling salamanders. The head plus body length is more than 7.5 inches (19 centimeters), and the total length is at least 13 inches (34 centimeters). The largest coastal giant salamanders on record were larvae found in large rivers. These larvae were about 8 inches (20 centimeters) in head plus body length and nearly 14 inches (35 centimeters) in overall length. The color of coastal giant salamanders varies. The background color of larvae usually is dark brown to black. As metamorphosis approaches, a silvery or dull golden color appears over the dark base and produces a marbling effect of light on dark. The marbling varies from fine to coarse. In some cases the marbling is so coarse that the underlying color cannot be seen.
Geographic range: Coastal giant salamanders live in an area that extends from southwestern British Columbia, Canada, southward west of the crest of the Cascade Mountains to northern California, United States. Some of these salamanders live in isolated areas in north central Oregon, east of the Cascade crest.
Habitat: Coastal giant salamanders live in and near clear, cold, rocky streams.
Diet: Coastal giant salamanders mainly eat frogs and small mammals, but they also eat worms, insects, and spiders.
Behavior and reproduction: Adult coastal giant salamanders are active at night and are secretive, but they sometimes are seen walking through leaves on rainy days in densely forested regions. When approached, these salamanders bark. They are one of the few salamanders that make a sound. Coastal giant salamanders also can be found on rainy nights as they try to cross roads in areas near breeding sites.
Scientists know little about the breeding habits of coastal giant salamanders. Eggs are fertilized inside the female's body, so scientists believe males make a sperm sac that the females pick up. Females lay large numbers of large eggs under large rocks that are at least partially underwater in streams. The eggs take several months to hatch, and scientists believe the females guard their nests while the eggs are developing. After hatching, metamorphosis takes about two years. Some coastal giant salamanders do not go through metamorphosis, but even though they look like larvae, they can reproduce.
Coastal giant salamanders and people: Coastal giant salamanders are rarely found and are little known to people.
Conservation status: Coastal giant salamanders are not considered threatened or endangered. The greatest risk to these salamanders is destruction of forests and the buildup of silt in streams. ∎
FOR MORE INFORMATION
Bernhard, Emery. Salamanders. New York: Holiday House, 1995.
Duellman, William E., and Linda Trueb. Biology of Amphibians. Baltimore: Johns Hopkins University Press, 1994.
Gunzi, Christiane. Amphibians and Reptiles of North America. San Diego, CA: Thunder Bay, 1995.
Lawlor, Elizabeth P. Discover Nature in Water and Wetlands. Mechanicsburg, PA: Stackpole, 2000.
Llamas Ruiz, Andres. Reptiles and Amphibians: Birth and Growth. New York: Sterling, 1996.
Petranka, J. W. Salamanders of the United States and Canada. Washington, DC: Smithsonian Institution Press, 1998.
"Coastal (Pacific) Giant Salamander, Dicamptodon tenebrosus." Northern Prairie Wildlife Research Center. http://www.npwrc.usgs.gov/narcam/idguide/diteneb.htm (accessed on April 21, 2005).
"Dicamptodon (Strauch, 1870) Giant Salamanders." Livingunderworld.org. http://www.livingunderworld.org/caudata/database/dicamptodontidae/dicamptodon (accessed on April 21, 2005).
Guillermo, G.L. "Pacific Giant Salamander." Colegio Franklin Delano Roosevelt, American School of Lima. http://www.amersol.edu.pe/ms/7th/7block/jungle_research/new_cards/11c/report11c_G.html (accessed on April 21, 2005).
Animal Life ResourceAmphibiansPacific Giant Salamanders: Dicamptodontidae - Physical Characteristics, Geographic Range, Diet, Behavior And Reproduction, Conservation Status, Coastal Giant Salamander (dicamptodon Tenebrosus): Species Account - HABITAT, PACIFIC GIANT SALAMANDERS AND PEO