Assessment of growth, survival, and organ tissues of caged mussels (Bivalvia: Unionidae) in a river-scape influenced by coal mining in the southeastern USA

Jennifer J Rogers; William F Henley; Amanda G Weberg; Jess W Jones; W Gregory Cope

doi:10.1016/j.scitotenv.2018.07.142

Assessment of growth, survival, and organ tissues of caged mussels (Bivalvia: Unionidae) in a river-scape influenced by coal mining in the southeastern USA

Sci Total Environ. 2018 Dec 15:645:1273-1286. doi: 10.1016/j.scitotenv.2018.07.142. Epub 2018 Jul 22.

Authors

Jennifer J Rogers¹, William F Henley², Amanda G Weberg¹, Jess W Jones³, W Gregory Cope⁴

Affiliations

¹ Freshwater Mollusk Conservation Center, Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, United States.
² Freshwater Mollusk Conservation Center, Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, United States. Electronic address: whenley@vt.edu.
³ Freshwater Mollusk Conservation Center, Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, United States; United States Fish and Wildlife Service, Blacksburg, VA 24061, United States.
⁴ Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695, United States.

PMID: 30248852
DOI: 10.1016/j.scitotenv.2018.07.142

Abstract

The Clinch River contains one of the most diverse freshwater mussel assemblages in the United States, with 46 extant species, 20 of which are listed as federally endangered. In a 91 km section of the Clinch River, mussel densities have severely declined at key sites from 1979 to 2014 (zone of decline), compared to other river sections that support high density and stable mussel populations (zone of stability). Coal mining has occurred in tributary watersheds that drain to the zone of decline since the late nineteenth century. To determine differences in survival, growth, and organ (gills, digestive glands, kidneys, and gonads) tissue health between the river zones, laboratory-propagated mussels were deployed to cages for one year at four sites each within the zones of mussel stability and decline. Means of growth and survival of mussels in the zone of stability were significantly greater than in the zone of decline, and mean fractions of kidney lipofuscin in mussels in the zone of decline was significantly greater than in the zone of stability. Water concentrations of K⁺, Na⁺, Al, and Mn were significantly greater in the zone of decline than in the zone of stability. Statistical correlation results indicated that mussel survival was positively associated with concentrations of Mn in water, and kidney lipofuscin was negatively associated with concentrations of dissolved K⁺, SO₄^2-, and Mg²⁺. Most concentrations of contaminants were below published benchmark criteria, yet our results suggest that conditions continue to exist in the zone of decline that promote impacts to mussels that are at least partially associated with low concentration coal-related contaminants. More research is needed to determine the additive, synergistic, or antagonistic effects of these complex ionic mixtures on freshwater mussels from river environments, such as in the Clinch River, where constituent concentrations are relatively low.

Keywords: Chemical mixtures; Clinch River; Freshwater mussels; Histology; Kidney lipofuscin; Lipid peroxidation.

MeSH terms

Animals
Bivalvia / physiology*
Coal Mining
Environmental Monitoring / methods*
Fresh Water
Rivers
Unionidae
Water Pollutants, Chemical / analysis*

Substances

Water Pollutants, Chemical