The Mysterious, Amphibious Giant

Outfitted in a dry suit, snorkel and mask, I observed juvenile salmon taking refuge in a small, clear pool of Portuguese Creek in the Siskiyou Mountains. I remained still as I counted the juvenile Chinook and Steelhead. Suddenly, a creature emerged from the pool’s depths. Its foot-long pink body swam like a snake, but had four legs and bright-orange, fuzzy appendages coming from each side of its head.

This mysterious animal quickly glided through the water toward the school of small fish. I remained still as the large, amphibious creature moved in front of my mask, opened its mouth wide, and gobbled up a juvenile salmon. My lucky observation of this predator-prey interaction fueled my passion for Pacific Giant Salamanders, and I would like to share that passion with you!

Photo by: S. Oster

Pacific Giant Salamanders belong to the family Dicamptodontidae. The one in the picture above looks like it lost a portion of its tail, perhaps due to predation.

Description: Pacific Giant Salamanders are one of the largest salamanders in the world, measuring over 14 inches long! They have marbled skin in a variety of colors including: brown, orange, gray, and purple. They have hardened toenails for climbing and digging.

Distribution: The Pacific Giant is a-year round resident of the coastal mountain areas of northern California, Oregon and Washington (with the exception of the Olympic Peninsula).

Habitat: They reside in undisturbed streams and mountain lakes. The spend most of their time under rocks or underground.

 

How can you tell the difference between larval and adult Pacific Giant Salamanders?

Larvae Photo by: S. Oster

Pacific Giant Salamanders in the larval life stage are smaller than the adults, only reaching a length of 8-10 inches. They also have orange gills on each side of the back of their head.

Larvae spend most of their time living in the streams feeding on a variety of aquatic invertebrates including insect larvae and crayfish. They have been known to eat some vertebrates such as juvenile salmonids and sculpins.

Larval Pacific Giants typically metamorphose into adults 18-24 months after hatching but can retain their gills for an aquatic adult stage (neoteny).

Adult_Photo by: S. Oster

The larvae lose their gills, grow a few inches in length, and gain a narrower tail while changing into adults.

Adult Pacific Giant Salamanders are primarily terrestrial, meaning they live on land. It is not understood why adults are rare as compared to the aquatic larvae.

Terrestrial adults can be found under surface debris and in underground tunnels. They hunt for prey such as snails, slugs, small mice, shrews, and other small land creatures.

Adults migrate back to the stream to reproduce. Females lay eggs in slow moving water in May and guard them until they hatch in December or January. The inch long larvae leave immediately to fend for themselves.

Pacific Giant Salamander Facts!
  • Pacific Giants are “sit and wait” predators, thrusting at their prey at high speeds.
  • When threatened, they can produce a low pitched barking sound.
  •  Pacific Giant Salamanders can live up to 25 years!
  • In British Columbia, Pacific Giant Salamanders are listed as endangered due to their limited range.
  • Their predators include weasels and otters, snakes, and large salmonids.
Gopher Snake eating a Pacific Giant Salamander_Photo by: S. Oster

References:

Nussbaum, R.A. 1969. Nest and eggs of the Pacific  Giant Salamander, Dicamptodon ensatus (Eschscholtz). Herpetologica 25:257-262.

Nussbaum, R.A., E.D. Brodie Jr., and R.M Storm. 1983. Amphibians and reptiles of the Pacific northwest. University of Idaho Press, Moscow, ID.

Parker, M.S. 1994. Feeding ecology of the stream-dwelling Pacific Giant Salamanders (Dicamptodon ensatus). Copeia 1994(3):705-718.

Stebbins, R.C. 1985. A field guide to western reptiles and amphibians. Houghton Mifflin Co., Boston, MA.

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