Lower Mississippi River Environmental Program. Report 7. An Ecological Evaluation of Five Secondary Channel Habitats in the Lower Mississippi River
Abstract
Chemical, physical, and biological attributes of the aquatic habitat of five Lower Mississippi River secondary channels were surveyed during summer (July) 1984; two of the channels were resurveyed during fall (October). Dikes at least partially restricted flow through two of the channels (Lakeport Towhead and Cottonwood Bar, river miles 470 and 528, respectively); flow through the remaining three (Wolf Island, river mile 935; Island 8, river mile 915; Profit Island, river mile 250) was not restricted. The channel at which flow was most restricted, Lakeport Towhead, showed both physical and chemical differences from the others. Electroshocking catches of fish were highest at Profit Island due to unusually large collections of catfishes. The macroinvertebrate assemblages found within the channels were similar overall, and they appeared to reflect the current speed and substrate conditions. The dike macrofauna was similar to that noted in earlier studies on the Lower Mississippi River. Dikes that block or greatly restrict flow through secondary channels produce habitats in which the macroinvertebrate and fish assemblages are quite different from undiked channels, at least when river stages are near or lower than the controlling elevation of the dikes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA196343
Entities
People
- C. H. Pennington
- C. R. Bingham
- John A. Baker
- Linda E. Winfield