ASSESSMENT OF LARVAL FISH CONSUMPTION BY GOLDEYE (HIODON ALOSOIDES) IN 2 MISSOURI RIVER BACKWATERS

The presence of large numbers of adult goldeye (Hiodon alosoides) in b ackwater habitats of the upper Missouri River, combined with the prese nce of many other native fishes and their larvae, has raised questions about the predatory effect that goldeye may have on the larval fish c ommunity. Goldeye and larval fishes were sampled in backwater habitats during April, May, July, August, and September of 1997. Peak relative abundance of adult goldeye coincided with peak relative abundance of larval fishes in July. We examined the stomach contents from 161 golde ye collected in July and August to determine what proportion of the go ldeye diet was composed of larval fishes. Only four stomachs contained larval fish (2.5% frequency of occurrence), and larval fishes compose d less than 0.1% of the total number of food items. Corixidae, Coleopt era, and zooplankton (Copepoda and Cladocera) were the primary diet it ems.