Montana Field Guide

Torrent Sculpin - Cottus rhotheus

The torrent sculpin is found only in the fast headwater streams of the Kootenai River drainage of northwest Montana. As with all sculpins, it presents a somewhat grotesque appearance with its large head, huge pectoral fins, and bulging eyes. Sculpins have a very flattened hydrodynamic shape, which serves them well as they dart along the bottom between the cracks and crevices of rocks.

This species is gray-brown with black speckling. The underside is light and the chin strongly mottled. The first dorsal fin is fringed with orange on spawning males. Palatine teeth are usually present. The body is robust. They usually have coarse prickles on the back, sides, and sometimes on the caudal peduncle.

Montana Range

These fish are typically found in the riffles of cold, clear streams, but are also taken in lakes. They hide near stones on the bottom.

The fry eat mostly plankton. Adults feed mainly on aquatic insects and a variety of invertebrates, but also include plankton. Larger individuals often eat small fish.

They are sexually mature in 2 years and spawn in late spring. The eggs hatch in 30 to 50 degrees F. The male remains close to the nest until after the eggs hatch.