More Endangered Mussels Shouldn’t Mean Changes for Utility

A mature and juvenile spectaclecase mussel. (Photo by US Fish and Wildlife Service; Tamara Smith)

Two more species of mussels found in Tennessee have been added to the endangered list. That designation comes despite concerns expressed by a local utility.

Spectaclecase and sheepnose mussels used to live in rivers throughout Tennessee and the Midwest. Now, they’re found in just a handful of waterways, one of which is the Duck River.

Columbia Power and Water urged the US Fish and Wildlife Service not to grant endangered status to the animals. The utility expressed concern that the listing could restrict how much it can use the river for drawing drinking water and disposing of treated wastewater.

But Leslie Colley says the utility doesn’t need to worry. The director of the Nature Conservancy’s Duck River office says the new listing shouldn’t add to the limits that are already in place.

“It doesn’t matter if there are three listed species or thirty. Those regulatory constraints were in place with the first listed species.”

Colley says there’ve been endangered mussels in the Duck River as long as there have been regulations protecting dwindling animal groups.

Two other species of Duck River mussels were granted endangered status last month. The river is considered one of the nation’s richest habitats for freshwater animals, including many that have died out in other places.

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In 1906, 200 spectaclecase were found clinging to a single rock in the Tennessee River. Now, it’s entirely missing in that river. In the Duck, which is a place where mussels are generally more likely to survive, only two or three have been found in the last decade or so.

The sheepnose is now considered locally extinct in the entire Cumberland River system (the river and its tributary rivers and streams). Within the Tennessee River system, it’s likely gone from even the Duck River, although two other tributaries do have surviving groups.

The health of mussels is looked at as one indicator of a waterway’s water quality. Because the animals take impurities into their bodies, they’re particularly sensitive to water pollution. Mussels populations are also damaged by dams. The mollusks live in shallow areas that are flooded out by the lakes and ponds that form when dams are built.