Fish Community Patterns in a
Northeast Texas Stream
Michael N. Morgan and Frances P. Gelwick Department
of Wildlife and Fisheries Sciences 210 Nagle Hall Texas A&M University College
Station, Texas 77843-2258 Voice 409-847-9335 FAX 409-845-4096 E-Mail mnm5694@acs.tamu.edu, fig0697@acs.tamu.edu
Keywords: habitat, woody debris, fish assemblage, flow regime,
Sulphur River, Texas
This study is designed to provide information about fishes downstream
of two proposed reservoir sites on the Sulphur River, Texas. Historic channelization and
logging operations appear to have altered the usual longitudinal habitat pattern. The
three sites in the upstream reach are straight and deep with a more open canopy than the
three sites in the downstream study reach, which are meandering, narrow, and shallower.
Pools are the primary mesohabitat type in both reaches, but more riffles occur in the
downstream reach. In both reaches, complex microhabitats are dominated by snags, rootwads,
and debris dams. Electrofishers, seines, and gillnets are used to sample fish at target
discharges within the normal flow regime. Samples to date indicate similar species
richness and relative abundances in upstream and downstream sections. However, smallmouth
buffalo (Ictiobus bubalus) are most abundant in the upstream reach, and red shiners
(Cyprinella lutrensis) are most abundant in the downstream reach. Results will
guide operation of the proposed dams for the purpose of mitigating further alterations to
fish communities due to impoundment.
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