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Tuesday, June 5, 2007 - 10:45 AM
143
Comparing the Responses of Fish Assemblages to Dams in Georgia Streams
Nick Ozburn and Carol Johnston. Department of Fisheries and Allied Aquacultures, Auburn University, Auburn, AL 36849
The abiotic factors influencing the persistence of stream fish assemblages are poorly understood. This is true for physiographic region, even though it has long been recognized that physiography has a strong influence on fish distribution. Streams from different physiographic regions may vary in elevation gradient, substrate type, turbidity, floodplain connectivity, and other factors. We compared the effect of an ecosystem disruption, non-hydroelectric dams, on fish assemblage persistence among three major physiographic regions in Georgia. Sample sites downstream of dams were compared with free-flowing reference sites in the same river drainage, physiographic region, and of the same stream size. Morisita Similarity between dammed sites and reference sites was calculated, and mean similarity was compared among the Ridge and Valley, Piedmont, and Coastal Plain regions of Georgia. In addition we assessed the impacts of dams on fish assemblages as a function of stream size. The responses of different fish guilds to dam-altered stream conditions and the life history characteristics that may render a species vulnerable will also be discussed.
See more of Special Session - Benthic vertebrates: Ecology and conservation of substrate-oriented fishes
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See more of The NABS 55th Annual Meeting
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See more of The NABS 55th Annual Meeting