Creek Heelsplitter
NDGF
Mussel with relatively thin shell, flattened, and elongated up to 3 inches in length. Typically, Creek Heelsplitters are yellow in color with green rays extending from the top. Larger shells are typically darker in color.
Status in North Dakota
Year-round resident but rare in abundance.
Range Map
Creek heelsplitter range in North Dakota.
Reason for SWAP Designation
This species is regionally at risk or declining and North Dakota represents an important portion of its range.
Changes in land use in/around rivers including agriculture and impoundments have impacted this species, specifically related to their beds.
Threats
Impoundments of the Red River and its tributaries have altered the flow regime creating unsuitable habitat for Creek Heelsplitters by increasing sediment deposition and blocking host fish movement.
Agricultural practices, along with wetland drainage, continue to degrade water quality.
Also, increased flow and altered water chemistry in the Sheyenne River from the Devils Lake outlet may pose additional threats.
Research and Monitoring
A monitoring protocol for mussels has been developed by the North Dakota Game and Fish Department (NDGF) under the State Wildlife Grant Program with increased implementation as a future goal.
Additionally, the North Dakota Department of Environmental Quality (NDDEQ) conducts biological monitoring surveys on State waters as part of their Index of Biotic Integrity (IBI) development.
Valley City State University (VCSU) conducted a twophase populations survey of mussels in 2008-2010 and began another evaluation in 2024.
Management Recommendations
- Develop/maintain buffers along riparian areas.
- Partner with local, state, and federal entities to limit chemical use in/near aquatic habitats.
- Continue partnering with local, state, and federal entities to maintain instream flows.
- Continue partnering with local, state, and federal entities to reduce wetland drainage.
- Remove river impoundments where possible.
- Encourage efficient use of pesticides.
Primary Geological Regions
Habitat Associations
Habitat Use
Creek Heelsplitters are found in the Pembina, Forest, Wintering and Sheyenne Rivers.
Generally, they are found in headwater areas with sandy substrates.