PFMC Habitat Committee raises alarm on invasive golden mussels, flags Coos Bay channel proposal and Columbia River EIS

The Pacific Fishery Management Council’s Habitat Committee on March 6 reported the discovery of invasive golden mussels in California waters, encouraged the council to consider comment on a proposed supplemental environmental impact statement for Columbia River operations and flagged a large Port of Coos Bay channel modification project as having potentially substantial habitat impacts.

The habitat update was presented by Gary Griffith and Dr. Scott Hapelle, vice chair of the council’s Habitat Committee. “The golden mussel is an invasive freshwater brackish bivalve native to China and Southeast Asia,” Hapelle said, summarizing the committee’s supplemental informational report and the state and federal response to detections last October in the Port of Stockton and San Luis Reservoir.

Why it matters: committee members warned the mussels can alter food webs and clog water infrastructure, putting municipal and agricultural water supplies, hydroelectric facilities and fish passage at risk. The committee also flagged near‑term comment deadlines and coordination needs for federal and regional reviews that may affect fish and habitat across the Columbia River Basin.

Key details and immediate actions

- Golden mussel detections and responses: Golden mussels were first found in October 2024 at the Port of Stockton and San Luis Reservoir. The committee said monitoring has since revealed additional detections primarily on the eastern side of the Sacramento–San Joaquin Delta. California added the species to its restricted list (prohibiting possession, import or transport of live mussels), closed or quarantined multiple reservoirs, and created a state task force working on a response plan. Hapelle noted the U.S. Fish and Wildlife Service proposed adding the genus to the Federal injurious wildlife list in Title 50 of the Code of Federal Regulations; that proposed rule was open for comment through March 11, 2025.

- Biological and infrastructure risks: Hapelle described the mussel’s biology and potential impacts: planktonic larvae, rapid colony growth and very high local densities — “colonies can reach densities of 5,000 to 250,000 individuals per square meter,” he said — with risks to native bivalves, zooplankton productivity, fish screens, water intake systems, and boat hulls.

- Regional coordination and monitoring: The Committee summarized state and regional actions: California is developing a statewide habitat suitability assessment and vessel‑movement tracking; Bureau of Reclamation is developing a more sensitive eDNA primer for surveillance; the California State Lands Commission has authorized emergency rulemaking to add fresh/brackish ballast water requirements and discharge standards for vessels into California's fresh and brackish ports; and multiple interstate and federal coordination groups have added golden mussels to regional response plans.

- Columbia River System supplemental EIS: The Habitat Committee reviewed a notice of intent by the U.S. Army Corps of Engineers and Bureau of Reclamation to prepare a supplemental EIS analyzing operations, maintenance and configuration changes since the 2020 CRSO EIS. The committee noted the comment deadline on the Notice of Intent is May 9, 2025, and recommended the council consider preparing a quick‑response draft comment letter if states and tribes coordinate recommendations.

- Port of Coos Bay channel modification: The committee described a large Pacific Coast Intermodal Port proposal for Coos Bay that would widen, deepen and extend the navigation channel about a mile offshore, create two deep‑draft turning basins, and authorize ocean disposal sites for as much as 20 million cubic yards of dredged material including rock. The project also includes a new terminal and rail upgrades and “would have substantial effects on estuarine and freshwater habitats,” the committee report said, citing potential changes to hydrodynamics, salinity regimes, eelgrass beds and invasive species risk. A notice of intent to prepare a draft EIS for the channel modification was expected in June 2025.

Committee posture and council direction

- The Habitat Committee asked the Council to consider tasking the committee to draft a comment letter on the Columbia River supplemental EIS using the quick‑response process if states and tribes coordinate comments; multiple council members voiced support for that approach during the meeting.

- The committee said it will continue to track the Coos Bay project and may recommend council comment on the channel modification and the broader Pacific Coast Intermodal Port project as they develop.

Public comment and council response

- A public commenter, Joel Kawahara, identified himself as a salmon chaser from Quilcene, Washington, and urged the council to comment on the Columbia River supplemental EIS because of the “essential fish habitat nexus” with operations that affect salmon. Several council members and the committee supported developing a quick‑response comment letter.

What’s next

- Deadlines noted by the committee: federal NOI comment deadline May 9, 2025; Northwest Power and Conservation Council amendment recommendations due April 17, 2025. The Habitat Committee will track the Coos Bay project and return to the council if it proposes drafting comment letters.

Ending note: Committee members said the golden mussel issue will be revisited at future meetings as monitoring and response efforts continue.