River Redhorse (Moxostoma carinatum)

Status: State Threatened (1989).

Occurrence: Mississippi, Rock, lower St. Croix, Sugar, Wisconsin, Black, Chippewa and the Yellow Rivers. A map outlining Pre-1977 and 1997 to Present Distribution is available.

Aid to ID: Red fins and thick fleshy lips distinguish river redhorse from other members of the sucker family. Moderately stout, round body. Bronze olive back, sides and belly yellowish or bronze. Head has a squared snout. Has molar-like throat teeth. Adult size: 12 inches (30cm).

Habitat: Prefer moderate to swift waters of large rivers, lower portions of their main tributaries, reservoirs and pools over clean gravel and rubble. Seldom found in deep water with mud, silt, or sand bottom.

Food Habits: River redhouse eat mollusks, larval ephemeroptera, chironomids and trichoptera. Their molar-like throat teeth are specialized for eating mollusks.

Natural History: Spawn during late March or early June. Females lay from 6000-23,000 eggs on nests in gravel which hatch in three or four days. They may make upriver spawning migrations.

Management Considerations: This redhorse species is quickly restored to waters from which they have been eliminated if there is a reservoir population nearby. Both the river redhorse and mollusks on which they feed are intolerant to siltation and turbidity.

Information compiled from publication ER-091.