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Pink Papershell

Pink Papershell

North Dakota Species of Conservation Priority I

Fact Sheet
Scientific Name Potamilus ohiensis
General Description Large mussel with a maximum length of 7 inches. Shell is elongated and generally rectangular. Wing present near the umbos. Shell dark green to brown. Nacre is pink.
Status Year-round resident.
Abundance Rare.
Primary Habitat Medium to larger rivers. Bottom substrate generally mud or sand.
Federal Status None.
Reason for Designation Changes in land use in around rivers, and impoundment have impacted beds of these mussels.


Pink Papershell
Pink Papershell

(Photos courtesy of Prairie Waters Education and Research Center - Valley City University)

Locations and Conditions of Key Habitat

Preferred Habitat

Pink Papershell prefer large river systems, but was collected only from tributaries of the Missouri River with a stream width of 14 to 30m. The substrate of the river is normally mud, sand, or gravel.

Key Areas and Conditions for Pink Papershell in North Dakota

Found only in the lower reaches of the Missouri River and tributaries below Garrison Dam in North Dakota.

Problems Which May Affect this Species


Impoundments built on the Missouri River System have changed the flow regime of the river. Water released from the dam is cooler, cleaner, and moving faster. This has changed the historic habitat conditions of the river system.

Other Natural or Manmade Factors

Impoundments in the system block movement of fish species used by the Pink Papershell as hosts for young. In this case, the most common host is the freshwater drum.

Research and Survey Efforts

Current Research or Surveys

  • No current research or survey efforts are on-going in this species range.

Previous Research or Surveys

  • Cvancara conducted a state-wide survey of the mussels of North Dakota in 1978.
  • The North Dakota Game and Fish Department revisited Cvancara’s sites in 1990.
  • Valley City State University revisited Cvancara’s sites and surveyed additional sites in 2008.
  • The NDDH conducted freshwater mussel surveys for state waters as a segment of its Index of Biotic Integrity (IBI) work.

Additional Research or Surveys Needed

  • A monitoring protocol for mussel species has been developed for the North Dakota Game and Fish Department under the SWG program. Implementation of this monitoring protocol is a future goal.

Management Recommendations

  • Develop buffers along riparian areas.
  • Work with partners to reduce the use of chemical near waterways.
  • Work with partners to reduce wetland drainage.
  • Remove river impoundments where possible.
  • Work with partners to maintain instream flows.

Monitoring Plans

A monitoring protocol has been developed for the North Dakota Game and Fish Department under the SWG program. Implementation of this monitoring protocol is a future goal.

2005-2015 Progress

Upgraded to a Level I Species of Conservation Priority in the 2015 revision of the Wildlife Action Plan. SWG T-24-R A Two Phase Population Survey of Mussels in North Dakota Rivers provided important information on the distribution of this species. Work to implement a monitoring protocol for mussels species will is a goal of the revised Wildlife Action Plan.

Range Map

Note: A listing of works consulted when compiling the information on this page may be found in the 2015 State Wildlife Action Plan.