Japanese Giant Slamanders

Japanese giant salamanders are about 55 pounds and five feet long. Brown and black skin helps them blend in with the mud, stones, and plants of the streambeds where they live. Their broad, flattened bodies are streamlined for swimming at the bottom of fast-moving water. Giant salamanders are covered in mucus, which protects their bodies from abrasions and parasites. When irritated or grasped, they produce a milky, sticky secretion that smells like Japanese peppers. The giant salamander absorbs oxygen through its skin. Loose folds of skin along its sides increase surface area to help absorb even more oxygen.

Distribution and Habitat: Japanese giant salamanders inhabit the cold, fast-flowing mountain streams and rivers of northern Kyushu Island and western Honshu in Japan.

Diet: With their tiny eyes, giant salamanders have poor vision. Instead, they rely on their other senses—such as sensory organs along their bodies and on their heads—to detect other animals and find their way. They eat almost anything they can, from insects to fish to mice to small invertebrates like crabs. Giant salamanders have a very slow metabolism, and go weeks without eating, if necessary.

Reproduction: Japanese giant salamanders begin reproduction in late August, when herds congregate at nest sites. Males compete, viciously, with many dying due to injuries from fights. Females lay between 400 and 500 eggs in the fall, which may be fertilized by several males. Males aggressively guard the nests, which may contain eggs from several females, until they hatch in the early spring.

Conservation: This giant salamander is protected from international trade by its listing on Appendix I of the Convention of International Trade of Endangered Species. It is listed as near threatened on the World Conservation Union's Red List of Threatened Species. It has no natural predators, but has been hunted by local populations for food, and is losing its habitat to deforestation.

About the Author

The Smithsonian National Zoological Park