The Pacific Giant Salamander is found along the West Coast of North America from northern California to southern British Columbia. Its range in British Columbia is only about 250 square kilometers, a meager 0.03% of the province. It is also only found in a limited area in California.
The Pacific Giant Salamander is found in a variety of aquatic habitats, including lakes, ponds, rivers, and streams. They prefer fast moving water to slow moving water. Cover is another vital characteristic of this Salamander's habitat. Cover is used for hiding, protection from the sun, and brooding eggs.
Like all salamanders, the Pacific Giant has an aquatic larval stage, and a terrestrial adult stage. The adult is stout-bodied with a long tail. It is very large, usually 30 centimeters or more in length. Its tail is about 40% of its total length, and is laterally compressed as an aid for swimming. The Giant Salamander has four toes on the front feet, and five toes on the hind feet. Pacific Giant Salamanders are often identified by their coloring. They have a distinct pattern of dark blotches on a light brown almost brassy-colored background. Color is known to vary widely within the range of this species.
Larvae of the Pacific Giant Salamander are streamlined and adapted for life in flowing water. They have small "fuzzy" gills behind their heads and a fin along the top and bottom of their tails.
Mature adults migrate to suitable streams or springs for breeding. This is believed to occur from spring to autumn, but not much is really known. The female deposits from 85 to 200 eggs, singly or in clumps, in a hidden subterranean or underwater nest site. The female protects these eggs for up to seven months. She aggressively protects them from being cannibalized by males or eaten by other predators, and eats little or nothing herself. When the larvae finally hatch, they live in the nest for another two to four months. During this time they do not feed but get energy from their yolk. Because of this long gestation period, females are only able to reproduce once every two years. They also do not reach sexual maturity until they are five or six years old. These things combined with the small number of eggs laid give this animal a relatively slow reproductive rate.
The Pacific Giant Salamander is particularly elusive, moving about and feeding mostly by night, and hiding by day. It is least active in winter. This is a response to the cold weather, because the animal is an ectotherm. Adults are capable diggers and climbers, and have hardened toes for this purpose. They frequently dig to find food and protective cover. They avoid brightly lit areas and direct sunlight, and prefer damp surroundings where their skin will not dry out.
These animals are known to be aggressive against any possible predators and those of their own kind. They bite, thrash the tail, try to look formidable, and use glands on the top of the tail to secrete foul tasting chemicals.
The adult and larval forms of the Pacific Giant Salamanders are predators. Adults feed on land snails and slugs; insects such as beetles, caddisfly larvae, moths and flies. They also eat small mammals such as shrews and white-footed mice; and other amphibians. Larvae feed on absolutely anything that comes near them. This includes insects, snakes, and small fish. In an experiment they were shown to grab anything attached to a hook, and refuse to let go of it, even when dragged from the water.
The Pacific Giant Salamander is sold as a pet in the United States where it is more common then in British Columbia.
The Pacific Giant Salamander is a rare species due to several factors, the most important of which are limited range, human activities, severe weather, and predation. The Pacific Giant Salamander is protected from killing or collecting under the Wildlife Act in British Columbia. It has been "red-listed" by British Columbia, meaning that it is being considered for "threatened" or "endangered" status.
Michelle Gonder (author), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
Encyclopedia Americana International edition. vol. 24. p. 144-145, 1994
Conant, Roger. 1975. A Field Guide to Reptiles and Amphibians. Houghton Mifflin Company, Boston, Massachusetts
Stebbins, Robert C.1951. Amphibians of Western North America. University of California Press, Los Angeles, California
Pacific Giant Salamander. 1997. The Ministry of Environment, Lands and Parks, Wildlife Branch. Victoria, British Columbia.