Invasive European Green Crabs Are Spreading in Washington

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Highly invasive European green crabs are spreading south in the Salish Sea.

Washington state has spent millions of dollars to contain the European green crab, a harmful invasive species that threatens native shellfish, eelgrass and estuary habitat that can be important for salmon.

Yet they remain stubbornly pervasive.

Earlier this month, the Washington Department of Fish and Wildlife increased funding, deployed emergency measures and strengthened coordination with other agencies, tribes and organizations after a European green crab was captured in Hood Canal in May — the furthest south the species has ever been found in the Salish Sea.

As of June 11, more than 64,000 European green crabs have been found and removed across the state, according to the department.

In January, Gov. Jay Inslee issued an emergency proclamation after the crabs were increasing exponentially within the Lummi Nation's Sea Pond and coastal areas in Whatcom County.

"The European green crab is a globally-damaging invasive species that, if they become permanently established, will particularly harm endangered species, impact resources that are part of the cultural identity of the tribes and native peoples, and affect small businesses," the proclamation stated.

In 2020, the discovery of 2,600 European green crabs — the most ever found in Puget Sound — on the shores of the reservation near Bellingham alarmed the Lummi Nation. Last year, they captured more than 70,000.

There and elsewhere, efforts are underway to prevent European green crabs from establishing themselves permanently.

In May, volunteers with Washington Sea Grant capture a male European green crab near Seabeck in Hood Canal, the first report of the species in Hood Canal and the southern most place they have ever been reported in the Salish Sea.

The crab arrived there last year based on its size, according to Washington Sea Grant's Crab Team.



The species arrived on the East Coast in the 1800s, most likely as stowaways. They have been present in the Pacific Northwest for more than a decade in the coastal estuaries of Willapa Bay and Grays Harbor as well as near Vancouver Island and off the coast of Oregon. In 2016, they were first discovered in Washington's inland waters.

The European green crab, or Carcinus maenas, is classified in Washington as a Prohibited Level 1 Invasive Species — the highest of three levels — meaning they "pose a high invasive risk and a are a priority for prevention and expedited rapid response management actions."

The Legislature appropriated $8.5 million toward eradicating the species earlier this year. In previous years, the state spent less — a one-time provision of $783,000 in 2020 and $2.3 million in ongoing funding in 2021 — but the funds weren't enough to contain the crabs.

Washington state, along with Washington Sea Grant's "Crab Team," the Lummi Nation, Makah Tribe, Shoalwater Bay Tribe and the Willapa-Grays Harbor Oyster Growers Association, have been monitoring, trapping and removing the crabs from Washington waters.

The department is working to secure an additional $1.1 million in funding to expand interagency coordination. It's also implementing a grant program to provide $675,000 in funding available for local, nonprofit and private entities looking to remove the crabs.

Washington Department of Fish and Wildlife says permits, traps and other support are available for tidelands owners.

The agency is not asking the public to keep or kill European green crabs because they can often be mistaken for native species.

Instead, it's asking people to take pictures and report any crabs or shells that appear to be the European green crab, either through the agency's reporting form, the WA Invasives app or by contacting ais@dfw.wa.gov.

European green crabs are often mistaken for other species, but identification guides can be helpful in spotting them.

Despite their name, these crabs aren't always green and their colors vary widely. Juveniles usually change color when they molt, and adults are typically dark green with yellow markings and orange joints.