Japanese giant salamander
Salamanders are opportunistic predators. They are generally not restricted to specific foods, but feed on almost any organism of a reasonable size. Large species such as the Japanese giant salamander ("Andrias japonicus") eat crabs, fish, small mammals, amphibians, and aquatic insects. In a study of smaller dusky salamanders ("Desmognathus") in the Appalachian Mountains, their diet includes earthworms, flies, beetles, beetle larvae, leafhoppers, springtails, moths, spiders, grasshoppers, and mites. Cannibalism sometimes takes place, especially when resources are short or time is limited. Tiger salamander tadpoles in ephemeral pools sometimes resort to eating each other, and are seemingly able to target unrelated individuals. Adult blackbelly salamanders ("Desmognathus quadramaculatus") prey on adults and young of other species of salamanders, while their larvae sometimes cannibalise smaller larvae.