The Freshwater Mussels (Unionidae) of Twin Creek, Southwest Ohio

Abstract

We surveyed the mussel fauna of Twin Creek in southwest Ohio and examined its distribution relative to several selected environmental parameters. Unionid presence was determined with visual searches at 36 sites across 76 krn in four counties. Fifteen species from the subfamilies Anodontinae, Ambleminae, and Lampsilinae were recorded, with nine species found alive at 17 of the 36 sites. Mussel species richness and species composition agree in general with historical studies of Twin Creek and other streams in the Great Miami River watershed, although some species have declined or been extirpated. The subfamily Ambleminae was almost completely missing from the area. The presence of three species only as dead and relic shells also may indicate a loss of species richness over the last few decades. Species richness values from Twin Creek were lower than for streams in central and northeastern Ohio.

Spatial and Temporal Trends of Freshwater Mussel Assemblages in the Meramec River Basin, Missouri, USA

“…Significant decreases in diversity and abundance and increases in extirpation of species were evident at historical survey sites in the Meramec River basin, a pattern that continues to be reported in multiple U.S. river systems (Warren and Haag 2005;Hanlon et al 2009;Wendeln et al 2009;Haag and Warren 2010). Although mussel populations in the Meramec River basin appear more stable in terms of diversity and abundance than other regions (e.g., Abell et al 2000), decreases in SOCC distribution indicate that increased mussel conservation actions in the basin may be warranted.…”