Description
Able to reach 30 cm in total length, the Coastal Giant Salamander is
one of the largest terrestrial salamanders. Most adults are only about
half of this length, however. It is generally brown with black mottling.
Confusing Species
The Coastal Giant Salamander is most similar to the Tiger
Salamander, which is also blotchy, but its snout is blunter than the
Coastal Giant Salamander. In addition, the ranges of the two species do
not overlap. In British Columbia, Tiger Salamanders are only found in areas
like the Okanagan Valley.
Distribution
In Canada, the Coastal Giant Salamander is limited to a small area in
southwestern British Columbia. To the south, it is found along the Coastal
coast to northern California.
Habitat
Steep mountain streams are the prime habitat for Coastal Giant Salamanders.
These fast flowing steams have many obstructions such as fallen logs that
form rapids, falls and splash pools. Just as important is the fact that
these obstructions prevent fish from moving upstream. This allows the Coastal
Giant Salamander to exist without competition or predation by fish.
Reproduction
Breeding occurs in the spring. The female lays large (more than half
a centimeter in diamter) eggs singly on the underside of rocks or logs.
The female will stay with the eggs until they hatch in the fall. It can
take two or three years for the larvae to transform at 10-15 cm in length.
In some populations in British Columbia, the larvae do not transform, but
reach maturity in the larval state. This strategy (neotony) is believed
to occur when conditions are particular harsh on land, or the aquatic habitat
is particular safe -- a permanent, fishless waterbody.
Natural history
Terrestrial Coastal Giant Salamanders live under logs or rocks. At times
however, they can be seen crawling about on the ground in the leaf litter
and even climbing in bushes or trees. Adults feed on a large variety of
insects and other invertebrates as well as small vertebrates: other salamanders
or small mammals like shrews or voles. The larvae also eat a wide variety
of insects, plus other amphibian larvae and small fish.
Conservation Concerns
As Coastal Giant Salamanders live in fishless streams, their habitat
has often been unprotected. They are senstive to disturbances in the mature
forests around their streams and thus have been effected by logging. The
government of British Columbia has placed the Coastal Giant Salamander
on their Red List of threatened and endangered species. Nationally they
are designated vulnerable by COSEWIC (the Committee on the Status of Endangered
Wildlife in Canada).
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