Catfish, Helogenes marmoratus

Streams are often sampled using small seines tied to brails pulled between two people. The seine can be set downstream of a particular habitat, like a submerged woody snag. The habitat is kicked and overturned, startling resident fishes into the net which is then lifted out of the water. Examples of fishes caught in this small blackwater stream are the catfish Helogenes marmoratus and tetra Hyphessobrycon heterorhabdus.