Anthropogenic impacts such as bridge sites can greatly alter established streambed morphology, associated ecology and flora and fauna. At bridge sites, streams are often channelized approaching the site and deep pools are created at the bridge site causing ecological alterations of faunal assemblages. However, restoring channels and reducing negative construction practices allows the return of natural habitats that are likely to include more sensitive species. Recent conservation studies have suggested that anthropogenic sites may serve as potential habitats for reestablishment of populations following a drought event. This study examined the impact of bridges on fish assemblages at first through fourth order streams in the Suwannee River Basin of South Georgia. Collections were made at bridge, upstream and downstream sites via seining and setting of gill nets. Assemblage structure at bridge sites was compared to bridge structure, biological and physiochemical factors at fourteen bridge sites. Fish assemblages were least diverse upstream of bridge sites, most diverse at bridge sites, and intermediate in diversity downstream of bridge sites. The results suggest that bridge sites, if properly engineered, can serve as valuable refuges for reestablishing fish assemblages up and down stream after events such as the severe drought that impacted South Georgia in 2011.
Bechler, David L. Dr.
"Effect of Bridges on Low Order Stream Fish Assemblages, South Georgia, USA,"
Georgia Journal of Science, Vol. 80, No. 2, Article 11.
Available at: https://digitalcommons.gaacademy.org/gjs/vol80/iss2/11