FISH ASSEMBLAGES WITHIN THE GREAT RIVERS OF THE UNITED STATES

Michael A. McClelland, Kevin S. Irons and Thad R. Cook   
Illinois River Biological Station, Illinois Natural History Survey, 704 North 
Schrader Avenue, Havana, Illinois  62644

      The Environmental Monitoring and Assessment Program of Great River 
Ecosystems (EMAP-GRE) has monitored a wide range of biotic and abiotic criteria 
on three great rivers of the United States.  Preliminary EMAP data from 
electrofishing surveys of 148 randomly selected sites on the Mississippi, 
Missouri, and Ohio rivers collected 60,586 fish in 2004.  Mean catch per run was 
significantly higher for the Mississippi (305.8) and Ohio (227.6) rivers 
compared to the Missouri River (90.6; P < 0.0001), with no significant 
difference between the Mississippi and Ohio rivers (P > 0.05).  However, the 
Mississippi (16.7) and Missouri (12.6) rivers had significantly higher diversity 
(numbers of taxa collected per run) than the Ohio River (11.8, P < 0.001), 
although differences were not significant between the Mississippi and Missouri 
rivers (P > 0.05).  Analysis of Similarity showed that fish assemblages between 
rivers were similar (R = 0.39), however non-metric multi-dimensional scaling 
suggests fish assemblage differences between the Missouri and Ohio rivers.  Fish 
assemblages from all three rivers were dominated by four common species, common 
carp Cyprinus carpio, emerald shiner Notropis atherinoides, gizzard shad 
Dorosoma cepedianum, and freshwater drum Aplodinotus grunniens.  This large-
scale, inter-river, multi-agency monitoring effort may likely provide further 
insight into large river fish population ecology.  


Keywords:  Environmental Monitoring and Assessment Program (EMAP), fish 
assemblages, Mississippi River, Missouri River, Ohio River.