Ashy (Columbia) pebblesnail (Fluminicola columbiana)

Photo not available for this species
Category: Molluscs
State status: Candidate
Vulnerability to climate change (More details)


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Climate vulnerability

Sensitivity to climate change


There is limited information on the sensitivity of the ashy pebblesnail to climate change. This species displays very similar traits and habitat requirements to the Olympia pebblesnail.

The ashy pebblesnail’s habitat range is believed to be restricted to the Columbia River Basin’s rivers, streams, and creeks, although its historic range encompassed Washington, Oregon, and Idaho. The ashy pebblesnail requires clear, cold, highly oxygenated streams, and therefore may be sensitive to changes in flow regimes and increases in water temperature that negatively impact dissolved oxygen levels and chemical and biological processes. Changes in flow regimes that increase nutrient runoff may cause dense algae blooms that impair or prevent the ashy pebblesnail’s access to important food resources (e.g., lithophytes).

The invasive New Zealand mudsnail (Potamopyrgus antipodarum) may be a direct competitor for food and habitat.

Confidence: Low

Exposure to climate change


  • Altered flow regimes
  • Reduced oxygen
  • Increased water temperatures
Confidence: Low


This species is identified as a Species of Greatest Conservation Need (SGCN) under the State Wildlife Action Plan (SWAP). SGCN-classified species include both those with and without legal protection status under the Federal or State Endangered Species programs, as well as game species with low populations. The WDFW SWAP is part of a nationwide effort by all 50 states and five U.S. territories to develop conservation action plans for fish, wildlife and their natural habitats—identifying opportunities for species' recovery before they are imperiled and more limited.
This species is identified as a Priority Species under WDFW's Priority Habitat and Species Program. Priority species require protective measures for their survival due to their population status, sensitivity to habitat alteration, and/or recreational, commercial, or tribal importance. The PHS program is the agency's main means of sharing fish and wildlife information with local governments, landowners, and others who use it to protect priority habitats for land use planning.