Date of Award

Spring 1976

Document Type



Life & Environmental Sciences

First Advisor

Gale Lewellen

Second Advisor

James Manion

Third Advisor

Guido Bugni


Parasite infestation of freshwater fish is encountered by the fisheries researcher and Montana fishermen alike. Frequently in the routine dressing of fish, a variety of worms or wormlike organisms will be noticed. It is not uncommon for the fisherman to recognize a certain organism repeatedly in a particular species of fish.No comprehensive parasite surveys have been published on Montana fishes. Some parasite information is available on salmoniform species in western Montana (Benson, 1961; Fox, 1962, 1965; Johnson, 1965; Mitchell, 1968; Canaris and Newell, 1969; Lockard, 1974). Three studies have also been conducted investigating particular parasites (Fox and Olson, 1965; Olson, 1965; Mitchell, 1970). After a careful review of these studies it was apparent that a parasite survey of fishes from the eastern slope and particularly the Missouri River drainage was lacking. Consequently an investigation of fish parasitism in the Missouri River would be original and useful.This study is a survey of helminth parasites taken from common fish species of the Missouri River. The study site is located in northeast Montana, five kilometers downstream from Fort Peck Dam (see figure l). Water is released from Fort Peck Reservoir through a hydroelectric plant situated below the dam, and continues downstream as the Missouri River.