Ambystoma gracile (Baird, 1859) Northwestern
Salamander (Ambystoma
gracile gallery)
Physical Description
Adult Ambystoma gracile are found as both metamorphosed, and gilled
adults. Metamorphosed adults are usually dark to light brown, or
grayish colored dorsally and ventrally. Northern populations may have yellowish flecks scattered from the head to tail. All species possess
large paratoid glands behind the eyes, and a rounded ridge along the upper
surface of the tail. Costal grooves are typically prominent.
During the breeding season, normal males become a
darker color than females, while the gilled adults will develop hypertrophied
hind limbs, less spotted feet, and an enlarged
glandular ridge on the tail. Transformed adults measure approximately 14-22cm from the snout to tip of tail, and gilled adults measure
approximately 24-26cm from the snout to tip of tail (Petranka 53). When threatened, Ambystoma gracile will secrete a white, sticky, noxious substance from paratoid glands located
on the head, tail, and body (Behler 290).
Distribution & Natural Habitat
Adult Ambystoma gracile are found in humid grasslands and dense forests from the Pacific Coast of Northern
California upward through British Columbia to the Southern most areas of Alaska. Terrestrial adults are mostly
fossorial.
Adults live in areas ranging from grasslands to dense forests, and occur from sea level to nearly 3,110 meters
(Petranka 54).
Ambystoma gracile can be found under rotting logs, leaves, or other damp substrates,
often times near stream banks.
 
Subspecies
A.g. gracile - Ranges from the Pacific Coast of California upward through British Columbia.
Ambystoma gracile gracile possesses two joints on the fourth toe on the hind limbs
(Behler 290).
A.g. decorticatum - Ranges from British Columbia upward to the Southern most tip of Alaska.
Ambystoma gracile decorticatum possesses three joints on the fourth toe on the
hind legs, and may have light colored flecks on the head, dorsum, and tail (Behler 290).
References
Behler, John L., and F. Wayne King. National Audubon Society
Field Guide to North American Reptiles and Amphibians.
New York: Knopf, 1979, 1996.
Center for North American Herpetology. (2003).
http://www.cnah.org/
(Accessed: 2000).
Frost, Darrel & AMNH. Amphibian Species of the World 3.0, an Online
Reference. American Museum of Natural History.
http://research.amnh.org/herpetology/amphibia/index.php. (Accessed:
2004).
Nature Serve Explorer (Database). Nature Serve.
http://www.natureserve.org/explorer/index.htm
(Accessed: 2000-2003).
Obst, Fritz Jugen, Udo Jacob, and K. Richter. Completely Illustrated
Atlas of Reptiles and Amphibians for the Terrarium.
Neptune City, NY: T.F.H. Publications, Inc., 1989.
Petranka, James W. Salamanders of the United States and Canada.
Smithsonian Institution Press, 1998.
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