Geographical Range Worldwide (except Antarctica)
Habitat Rivers, streams, lakes, ponds
Scientific Name Order: Siluriformes
Conservation Status Common

Catfish are a large and diverse group of fish found all over the world. Though a few types inhabit the ocean, the majority lives in freshwater. Catfish can be easily recognized by the so-called "whiskers" (barbels) that give them their name. And most can also tolerate low-oxygen water. But beyond that, the 2,000+ species vary widely in shape, size, and habits.

Some species are quite small. Others reach gigantic sizes -- more than eight feet long! Many catfish are bottom feeders, eating algae and decaying material off stream bottoms. But not all do this: some catfish are meat-eaters, others eat only plant material, and still others eat both.

Most catfish are not threatened in the wild, though there is concern about the status of more than 60 species.