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Presented at the NABS Annual meeting, Vancouver, British Columbia, 2004
in Disturbance Ecology 1
Speculation on habitat loss and community change in rivers impacted by long-term flow Increases from proposed coal bed methane production in the Northern Great Plains.
J.A. Gore. Department of Environmental Science, Columbus State University, Columbus, GA 31907
A primary concern is the potential disruption of the integrity of riverine communities when flows are enhanced by surficial releases from proposed CBM production in the Northern Great Plains, especially the Powder and Tongue River basins. Regional hydrogeologists have predicted daily increases in flows of from 20% to 80%. Habitat evaluations for several rivers were performed for sauger, shovelnose sturgeon, the endangered western silvery minnow, and benthic macroinvertebrates. Greatest habitat losses, from 40% to 65% for more than 28 consecutive days, were predicted at all locations for the western silvery minnow and for macroinvertebrates. Losses in the richest habitat patches under high flows were over 75% during prolonged periods of high flow. Habitat loss creates a mosaic of habitat patches, becoming increasingly small and more isolated from each other. Numerical models from Haddad and Lande and systems models from Odum, and assuming limited dispersal for larval fish life stages and for most invertebrates species, predicted declines in secondary production and a concurrent loss of species from higher trophic levels. A reduction or loss of 20 to 30 benthic species, and as many as five fish species, can be predicted for project operation (continuous high flows) of 20 years.
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