Washington Dreissenid Mussel Rapid Response Plan (2017)

In 2007, both zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis) were found to have established populations west of the Rocky Mountains, and in 2016, the perimeter of the Pacific Northwest was breached when dreissenid veligers were detected in two Montana reservoirs.

The risk posed to the Pacific Northwest by the proximity of these new infestations is significant. This plan was developed in response to the increasing likelihood of the successful transport and introduction of these species into the State of Washington and Pacific Northwest. Although prevention remains the most cost-effective means of addressing potential infestations of aquatic invasive species, if prevention efforts fail, the State of Washington must be prepared to respond rapidly and effectively to minimize environmental and economic impacts and reduce the risk of spread.

The purpose of this plan is to identify prevention and contingency efforts to protect Washington’s waters, outdoor recreational resources, aquatic resources, and facilities from the deleterious effects of dreissenid mussel establishment. This plan serves as a guidance document for natural resource managers to plan for and provide a rapid response effort to a dreissenid mussel infestation in Washington waters. This plan is intended to complement the Columbia River Basin Interagency Invasive Species Response Plan: Zebra Mussels and Other Dreissena Species drafted by the Columbia River Basin 100th Meridian Team as well as provide stand-alone guidance should mussels be found in Washington, but outside of the Columbia River Basin. This plan applies to all dreissenid mussels, although the current focus is on zebra and quagga mussels. Many of the strategies listed herein can be applied to rapid response efforts for other aquatic invasive species (AIS) of concern.¹

¹ Although devised specifically to respond to dreissenid mussels, this plan should be useful for responding to any invasive freshwater animal. Freshwater plants fall under the purview of the Washington Department of Ecology (Water Quality Program) and are governed by different rules and regulations regarding response. Marine plants and animals will require unique considerations not included in this plan.