Channel incision has major impacts on stream corridor ecosystems. Rehabilitation strategies may be guided by conceptual models of incised channel evolution and fish community structure in small warmwater streams. These models indicate that rehabilitation efforts should focus on aggradational reaches in the downstream portions of incising watersheds, and that ecological status can be improved by inducing formation and maintenance of stable pool habitats.
Rehabilitation increased pool habitat availability, and made the treated sites more similar to the lightly degraded reference site. Fish communities generally responded as suggested by the aforementioned conceptual model. Species composition shifted away from small colonists (principally cyprinids and small centrarchids) toward larger centrarchids, catostomids, and ictalurids.
These experiments suggest that major gains in stream ecosystem rehabilitation can be made through relatively modest but well designed efforts to modify degraded physical habitats.