Freshwater Mussels of the National Park Service Obed Wild and Scenic River, Tennessee

Ahlstedt, Steven; Connell, Joseph; Bakaletz, Steve; Fagg, Mark

ABSTRACT: The Obed River was designated as a Wild and Scenic River (WSR) in 1976 and is a unit of the National Park Service. The river is considered to be among the highest quality in the state of Tennessee supporting a rich ecological diversity. Two federally listed species (one fish and one mussel) occur in the Obed: spotfin chub Cyprinella monacha, and purple bean Villosa perpurpurea. The Obed is a major tributary to the upper Emory River. Historical mussel collections and recent sampling have documented 27 species in the drainage. Freshwater mussel sampling was relegated to the Obed WSR and tributaries to determine species composition, abundance, and whether reproduction and recruitment is occurring to the fauna. Mussel sampling was conducted from 2000-2001 within the boundaries of the WSR at access points throughout the length of the Obed including portions of the upper Emory River, Daddy’s, Clear, and Whites creek. A total of 585 mussels representing nine species were found during the study. The most abundant mussel found was Villosa iris that comprised 55% of the fauna, followed by Lampsilis fasciola 19% and Medionidus conradicus 14%. The federally endangered V. perpurpurea was represented at 3%. Two species, Pleuronaia barnesiana (live) and Lampsilis cardium (fresh dead), were found as single individuals and P. barnesiana is a new distribution record for the Obed. The mussel fauna in the Obed WSR is relatively rare and historically the river may never have had a more diverse fauna because of the biologically non-productive nature of shale and sandstone that characterize streams on the Cumberland Plateau. Mostly larger size-class mussels measured suggests older adult individuals with minimum or no recruitment of some species to the fauna. Mussel reproduction and recruitment may be exacerbated from human activities outside the boundaries of the WSR, which influence the quality of water within its boundaries.

Freshwater Mussels of the National Park Service Obed Wild and Scenic River, Tennessee

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