HR: 11:30h
AN: NB52B-05    [Abstracts]
TI: Segment and Reach Scale Geomorphology and Associated Fish Assemblages in the Cheyenne River Basin
AU: Duehr, J P
EM: jeremyduehr@hotmail.com
AF: Deparment of Wildlife & Fisheries South Dakota State University, Box 2140B, Room 138 SNP, Brookings, SD 57007 United States
AU: * Hoagstrom, C W
EM: pecospupfish@hotmail.com
AF: Deparment of Wildlife & Fisheries South Dakota State University, Box 2140B, Room 138 SNP, Brookings, SD 57007 United States
AU: Berry, C R
EM: charles.berry@sdstate.edu
AF: South Dakota Cooperative Fish and Wildlife Research Unit South Dakota State University, Box 2140B, Room 138 SNP, Brookings, SD 57007 United States
AB: We used bankfull width, maximum bankfull depth, reach slope, and median substrate particle size to characterize 58 stream reaches in the Cheyenne River Basin, South Dakota including the mainstem Belle Fourche and Cheyenne rivers and their tributaries. We collected fishes from all reaches to investigate correspondence between geomorphology and fish assemblage composition. Cluster analysis grouped 56 reaches into medium-river, small-river, flat-stream, and steep-stream groups. Small- and medium-river reaches were sequential along the lower mainstem Belle Fourche and Cheyenne rivers. Flat- and steep-stream reaches were intermixed among tributary streams and the upper mainstems. We collected a total of 38 fish species. Ten favored riverine reaches and 10 others favored flat- or steep-stream reaches. Species richness and faunal similarity (Morisita's Index) were highest in small-river reaches and lowest in flat- and steep-stream reaches. Small-river reaches had the most distinct fish assemblage with relatively high species richness and faunal similarity. Environmental harshness and isolation from stable (source) fish assemblages apparently reduced richness and faunal similarity among flat- and steep-stream fish assemblages. This suggests faunal composition of stream reaches would be difficult to predict despite habitat similarity.
DE: 1824 Geomorphology (1625)
DE: 1869 Stochastic processes
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly