Freshwater Mussel Observations

Freshwater mussel shell Freshwater mussels are an important part of aquatic ecosystems. They filter water, provide a food source for wildlife and can be found in many different aquatic habitat areas, including streams, rivers, and lakes. Unfortunately, freshwater mussels are the most imperiled group of animals in the world, with over 75 percent of North America's species listed as endangered, threatened, or a species of concern.

Click here to start reporting observations (registration is required)

The Washington Department of Fish and Wildlife (WDFW) is collecting information about the distribution and abundance of freshwater mussels around the state. If you spend time in lakes or rivers where freshwater mussels may be present, you can help gather this information.

As you swim, kayak, canoe, hike, fish, or otherwise spend time in freshwater, keep track of any freshwater mussels you see, whether alive or dead. Submit one report per location. In general, mussels are easiest to see during late summer, when stream levels are lowest.

WDFW is most interested in reports from areas where no freshwater mussel observations have been reported and also reports from historical observation sites as shown on this web map. You will be able to see all records for freshwater mussel locations. Specific locations from this form will be displayed publicly. You can also make changes after you have submitted the form. WDFW will use these reports to inform studies, conservation, and management decisions.

Please note that handling live freshwater mussels requires a state scientific collection permit. Empty shells can be handled and collected. This quick ID guide illustrates how to identify mussels by siphon characteristics when they are found live, and by shell characteristics when found dead.

If you have any questions please contact Chris Sato ( or Liz Bockstiegel (