European Green Crab 2025-2031 Management Plan for Washington

The European Green Crab 2025-2031 Management Plan for Washington (hereafter the Plan) has been facilitated by the Washington Department of Fish and Wildlife (WDFW) and developed in collaboration with tribal governments, U.S. federal agencies, Washington state agencies, shellfish growers, and additional partners throughout Washington. The Plan was developed in recognition that European green crab (hereafter, green crab) pose a significant, long-term threat to Washington's coastal ecosystems and species, as well as the economic, cultural, recreational, and subsistence resources of tribes and coastal communities. Management of green crab along the vast coastline of Washington poses a difficult challenge requiring a long-term, collaborative approach emphasizing local management with WDFW oversight as the state lead management agency. Not only must efforts be made to detect and rapidly respond to the introduction of green crab to new locations, but continual control efforts are necessary at locations where established populations threaten priority resources.

Green crab (Carcinus maenas) are a highly invasive species whose ecological and economic damage is well-documented on both coasts of North America. On the Pacific coast, green crab were discovered in the late 1980s and spread northward into Washington in the late 1990s. Green crab are a globally notorious invasive species that can tolerate broad temperature and salinity ranges. Individual green crab females can produce hundreds of thousands of larval offspring that can disperse over hundreds of kilometers along coastal regions. The diet of green crab is diverse, including eelgrass, bivalve mollusks, crustaceans, polychaetes (marine worms), and other prey. Green crab are implicated in historic declines and current losses of commercial bivalves in the eastern U.S. and maritime Canada, as well as impacts to native species, including eelgrass habitats along both coasts of North America. While the assessment of the current impacts of green crab in Washington is being determined, many habitats, species, indigenous cultural resources, and coastal community assets are at risk of significant damage. 

On January 19, 2022, Governor Jay Inslee issued an emergency proclamation (#22-02) to address the exponential increase in the green crab numbers within the Lummi Nation’s Sea Pond and Pacific coastal areas. The proclamation directed WDFW to implement emergency measures as necessary to affect the eradication of or to prevent the permanent establishment and expansion of green crab in Washington. In December 2023, Governor Inslee, the Office of Financial Management, and the State Legislature directed WDFW to develop a comprehensive long-term plan for Washington’s response to European green crab (Engrossed Substitute Senate Bill 5950 – Operating Budget 2023-2025 Supplemental). While the Plan was already under development at the time of the request, the objectives of the Plan expanded to incorporate specific requirements from the Governor and legislature. 

The following fifteen objectives are the focus of the Plan: 

1. Establish processes for collaborative and transparent management across the entirety of Washington.
2. Maximize early detection in areas where green crab have not been detected. 
3. Maximize reduction or negation of green crab impacts via population reduction or containment.
4. Reduce the risk of human-mediated movement of green crab.
5. Provide clear communication and guidance regarding science-based green crab management strategies and techniques.
6. Establish methods and capacity for long-term monitoring of community structure to observe changes in populations of green crab and native species.
7. Provide clear communication and guidance on necessary data standards and submission to inform management of real-time status and trends. 
8. Provide a systematic approach to respond to confirmed detections of green crab in new locations.
9. Establish the capacity for local co-managers, tribes, and partners to transition to long-term green crab management with WDFW support and oversight.
10. Identify research that should be performed or promoted to support management.
11. Identify outreach and communications opportunities to support management and enhance local stewardship.
12. Provide clear communication and guidance about the acquisition and distribution of funding to allow for appropriate long-term planning. 
13. Provide procedures for the sustainable and beneficial disposal or use of green crab and other fish waste.
14. Provide safety guidance and training, where feasible, for participants. 
15. Outline the objectives of field operations for all co-managers, tribes, and partners, across the state.

The focus of the Plan is to provide guidance and information for current and new participants in green crab management activities, document actions planned by and identify needs of co-managers, tribes, and partners. The initial sections of the Plan focus on providing background information on the green crab emergency in Washington, then provide guidance and information to aid the planning and execution of green crab management actions. The latter sections of the plan lay out the Statewide and Management Area Objectives and the associated actions, and identifies needs (e.g., initial research, funding, and resource gaps) that must be addressed. WDFW utilizes the outlined actions and the associated gaps to inform funding recommendations to the legislature.

The Plan is intended to be a living document, subject to adjustment and change as the green crab situation changes over time. Reviews and updates will be facilitated by WDFW on a regular basis throughout the 2025-2031 period and beyond.