Endangered Carolina Heelsplitter mussels released into Lancaster County creek

April 17, 2024

The S.C. Department of Natural Resources (SCDNR) has released 500 endangered Carolina Heelsplitter mussels, Lasmigona decorata, into Lancaster County’s Flat Creek, near Flat Creek Heritage Preserve, which features the locally famous 40-Acre Rock.

The area where the mussels were released is owned by the Katawba Valley Land Trust (KVLT), which assisted with the mussel augmentation. The U.S. Fish and Wildlife Service’s National Fish Hatchery in Orangeburg, which raises Carolina Heelsplitters along with SCDNR, also assisted in the release of mussels in Lancaster County.

"This is an incredibly important event," said Robert H. Boyles Jr., SCDNR director, who took part in the mussel augmentation and placed a number of mussels into Flat Creek. "Our state is growing rapidly, and we need to work to ensure the things that make South Carolina so special—like the Carolina Heelsplitter—are here for future generations to enjoy."

SCDNR began its freshwater mussel program in 2018 at Cohen Campbell Fish Hatchery in West Columbia. These rare freshwater mussels are federally endangered and found only in the Carolinas. The 500 mussels that were released into Flat Creek are mostly less than an inch long and are about 14 months old. They are part of a "cohort" of more than 2,500 mussels that were raised at Cohen Campbell in 2023-24. Each mussel carries a "pit tag" that features a microchip so the mussels can later be located. Under normal conditions, Carolina Heelsplitters may only move about 12 feet during a year’s time.

"Augmenting hatchery-produced animals will help to keep these mussels in the landscape to reproduce on their own when their habitat stabilizes," said Morgan Kern, SCDNR mussel program coordinator.

Carolina Heelsplitters and other freshwater mussels help establish the foundation of ecosystems and are vital for water quality. These animals are natural filters and help to remove algae and bacteria from streams by feeding on them. Kern estimated the life span of a Carolina Heelsplitter to normally be about 20 years. She said some Midwestern mussels, which are much larger than Carolina Heelsplitters, may live as long as 150 years due to the greater amount of calcium available to them in Midwestern waters.

Although it was once found in large rivers and streams, the Carolina Heelsplitter is now restricted to cool, pollution-free, heavily shaded streams of moderate gradient. Stable streambanks and channels, with pool, riffle and run sequences, little or no fine sediment, and periodic natural flooding, appear to be required for the Carolina Heelsplitter.

"Katawba Valley Land Trust appreciates working closely with other organizations to help protect the flora and fauna found here in the Piedmont, including the endangered Carolina Heelsplitter mussels," said Michelle Evans, KVLT executive director. "Our organization is able to provide protection of the natural riparian buffer that helps the water quality in Flat Creek to be what the mussels need through ownership of the land. The mission of the Katawba Valley Land Trust is to protect the natural resources, cultural resources, open lands, waters, and vistas of aesthetic value in the Catawba River Valley and surrounding areas. We enjoyed being a part of such an important, amazing experience."

The Carolina Heelsplitter is vulnerable to a variety of threats related to human disturbance. Polluted wastewater from sewage treatment plants and industrial discharges are a threat. Stormwater runoff carrying silt, fertilizer, pesticides, and other pollutants threatens the Carolina Heelsplitter, especially when erosion and stormwater control is inadequate. Habitat alteration including impoundments, channelization, dredging, and streambank scouring by stormwater runoff have also contributed to the decline of the Carolina Heelsplitter.

You can help protect Carolina Heelsplitter and the other freshwater mussels of the state by allowing plants to grow near waterbodies, properly disposing of waste and being aware of how water drains on your property.

The Katawba Valley Land Trust is a private, non-profit conservation organization dedicated to the protection of natural resources, open lands, waters and historic resources in the Catawba River Valley and surrounding areas. To learn more, visit www.kvlt.org.