Communities of aquatic macroinvertebrates, fish density and biomass, and environmental variables were investigated in three Patagonian mountain rivers affected by urbanization. The rivers Las Minas, Esquel and Carbón that flow through the towns of Cholila, Esquel and Corcovado, respectively (northwest Chubut, Argentina) were selected to assess the degree of impairment. A reference site and an u...

The study was carried out to ascertain benthic macro-invertebrates checklist in the Cross River, Nigeria and using it for bio-indication of the river quality. A total of 186 benthos specimens were collected. The phylum Insecta was most abundant (96) representing 51.61% of total benthos abundance; followed by Oligochaeta 60 (32.25%), Nemertea 10 (5.37%), Hirudiae 8 (4.3%), Cladocera 6 (3.22%), A...

We examined inter-habitat variation in benthic macroinvertebrate assemblages in the 180-km Garrison Reach of the Upper Missouri River, North Dakota (USA) in 2001–2003. The Garrison Reach is unchannelized with a mostly rural setting. Flows are regulated by Garrison Dam.We sampled benthos from three habitats defined a priori: channel, shoreline, and backwater. Benthic assemblages were different i...

The ecological effects of water hyacinth (Eichhornia crassipes), an introduced macrophyte, in freshwater systems depend on the growth and extent of floating mats. We studied macroinvertebrates associated with roots of water hyacinth in the Waccamaw River, a blackwater, tidal river in northeastern South Carolina, USA. In this system, water hyacinth is limited to a few protected bays and backwate...