Dall’s Ramshorn

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  • Species Common Name Dall's Ramshorn
  • Species Scientific Name Vorticifex effusa dalli


Special needs

Dall's ramshorn is found in spring-influenced areas of large lakes. This species is now restricted to Upper Klamath Lake.

Limiting factors

This species has a very restricted distribution. Habitat loss, including spring alteration and decreased water flow, represents a major threat to Dall's ramshorn. Sedimentation and nutrient inputs from dredging, mining, road construction, and other land use practices may smother substrates or reduce egg survival.

Conservation actions

Maintain appropriate water flow and quality. Prevent or mitigate for water diversions, dredging, or other activities that could increase sediment or nutrient levels.