The abundance and species composition of larval fishes in the Missouri
River below Garrison Dam, North Dakota, was assessed during May-Augus
t of 1993 and 1994. Only Catostomus spp., Ictiobus spp., Moxostoma spp
., Stizostedion spp., Osmerus mordax, and Perca flavescens were collec
ted during the course of the study. Larval fish species diversity and
abundance were lower than expected given the number of adult fish spec
ies found in the tailwaters and numbers of larval fishes collected in
other studies on the Missouri and Mississippi rivers. The low abundanc
e and diversity likely were due to the hypolimnetic discharge of cold
water from Lake Sakakawea. Larval fish species also appeared later in
the season than expected.