Western ridged mussel (Gonidea angulata)

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


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Climate vulnerability

Sensitivity to climate change


There is limited information regarding the sensitivity of the Western ridged mussel to climate change. This species is generally found in shallow pools of freshwater creeks and streams and with good water quality and a sufficient abundance of small fish (e.g., sculpin and perch) who serve as hosts for mussels during their transition from the larval to juvenile stage. Therefore, their main sensitivity is likely to stem from climate-induced changes in water quality and host fish abundance. For instance, increased intensity of winter storms could lead to higher flow in rivers and increased nutrient runoff, both of which would degrade and reduce available mussel habitat. Additionally, increases in water temperature could lead to altered abundance of host fish for larval stage mussels, thus triggering declines in abundance, particularly since this species appears to be a specialist in terms of preferred host fish species. Western ridged mussels may also be sensitive to increasing water temperature in streams and creeks; increased temperatures could lead to decreased recruitment and increased mortality of larval stage mussels.
Confidence: Low

Exposure to climate change


  • Increased water temperatures
  • Altered flow regimes
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.