A Summary of Information on Sturgeon Chub in Montana

Abstract

The sturgeon chub (Macrhybopsis gelida) is a Montana species of special concern and a candidate species for federal listing. ft has been reported as having limited distribution and numbers in Montana. However; recent surveys shau, sturgeon chub are present in long reaches in the Powder, Yellowstone and Missouri rivers in Montana and number in the hundreds. Chub were collected at sites with average depths of 0.1 - 6.4 m over bottoms composed of sand to cobble. Most of the presumed ripe fish were collected in July. Forty eight species of fish are reported as associates of sturgeon chub with flathead chub (Platygobto gracilis) the most frequent. The average fin ray and lateral line scale numbers of specimens from the Powder; Yellowstone and Missouri rivers, respectively, were within one unit of each other and indicated no subspeciftc differentiation in chub among rivers. l concluded that sturgeon chub in Montana are more widespread in secure habitats and are not as rare as earlier believed.