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Surveys for Native Freshwater Mussels in the Potomac River. Extinction rate estimates for North American fauna 1. 1 Ricciardi and Rasmussen. 1999. Conservation Biology 13:1220-1222 2 percent loss per decade (extinction rate in tropical rainforest is 1 to 8%). Life Cycle.
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Surveys for Native Freshwater Mussels in the Potomac River
Extinction rate estimates for North American fauna1 1 Ricciardi and Rasmussen. 1999. Conservation Biology 13:1220-1222 2 percent loss per decade (extinction rate in tropical rainforest is 1 to 8%)
Life Cycle Picture provided by NC Resources Commission U.S. Department of the Interior U.S. Geological Survey
Lampsilis reeveiana, broken-rays mussel Lampsilis cardium, plain pocketbook U.S. Department of the Interior U.S. Geological Survey M. C. Barnhart
Ptychobranchus occidentalis, kidneyshell M. C. Barnhart U.S. Department of the Interior U.S. Geological Survey
*MDNR 1997 U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
Mussel Survey in the C&O Canal NHP U.S. Department of the Interior U.S. Geological Survey
Mussels Species in the C&O Canal U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
Mussel Populations in the Park Densities considered low (0.11 to 0.61/m2) Total density 0.21/m2 (SE = 0.07) Total abundance 170,479 (91,322 – 254,966) U.S. Department of the Interior U.S. Geological Survey
U.S. Department of the Interior U.S. Geological Survey
Sample Design Phase One Qualitative Survey Sediment, Corbicula analyzed for aluminum Phase Two Quantitative Survey U.S. Department of the Interior U.S. Geological Survey
A1 E. complanata 100% A2 E. complanata 100% E. complanata 50% U. imbecillis 50% A3 E. complanata 100% A4 S. undulatus 100% A5 Little Falls Dam U.S. Department of the Interior U.S. Geological Survey
Little Falls Dam E. complanata 97.1% L. cariosa 1.5% P. cataracta 0.74% A. implicata 0.74% B2 Delacarlia Reservoir U.S. Department of the Interior U.S. Geological Survey
U. imbecillis 85.7% P. cataracta 14.3% 45A E. complanata 100% 44.8 44.6 E. complanata 100% E. complanata 97.9% P. cataracta 1.67% A. implicata 0.06% L. ochracea 0.26% L. radiata 0.13% 43.2 E. complanata 80.7% L. radiata 1.02% L. ochracea 6.62% P. cataracta 10.94% U. imbecillis 0.76% 43 U.S. Department of the Interior U.S. Geological Survey Georgetown Reservoir
Effect of Drought on Mussels • Flow velocity <0.01 m/s mortality increased • Dissolved oxygen < 5 mg/L mortality increased • Elliptio complanata considered tolerant • Rare and riffle species most sensitive • Behavior change triggered by low DO and temperature U.S. Department of the Interior U.S. Geological Survey
Behavioral Response to Drought U.S. Department of the Interior U.S. Geological Survey
Research Needs Minimum flow and DO requirements Quantify non-lethal effects Post-drought response of populations Effects on host populations U.S. Department of the Interior U.S. Geological Survey