Washington will soon have another tool to support long-term management for one of the highest-priority invasive species, European green crab, thanks to additional state funding dedicated to genetic research. Last fall, Washington Sea Grant received $185,000 in state appropriations to work with the Washington Department of Fish & Wildlife and the Woods Hole Oceanographic Institution to sequence the European green crab genome. That work is underway. The European green crab, which has had severe impacts on the East Coast shellfish industry and can harm important eelgrass and estuary habitats, is listed as a priority species for the Washington Invasive Species Council and is a top management priority for the Washington Department of Fish & Wildlife, the state’s jurisdictional lead for aquatic invasive species. Washington Sea Grant, housed within the University of Washington College of the Environment, has hosted an extensive green crab-monitoring program since 2015.

In early 2022, Gov. Jay Inslee issued an emergency proclamation in response to growing populations of European green crab in Washington waters, including in Grays Harbor and the Willapa Bay. As of 2024, European green crab infestations have been found along much of Washington’s Pacific Coast and in the Salish Sea. Existing genetics research indicates that all the European green crab along the Pacific Coast of the U.S. and Canada originated from a single introduction event to San Francisco Bay from the northeastern United States. However, a deeper investigation of the European green crab genetic makeup is still needed to understand how the species could continue to spread and to form the basis for potential management strategies. Mapping the genome of the European green crab will provide crucial information such as how genes play a role in enabling green crabs to adapt to a variety of environments including changing water temperatures along the Pacific Coast. “The green crab is one of the most successful invasive species globally, and a large part of that success is its adaptability to a wide range of variable marine habitats,” said Emily Grason, marine ecologist and lead of the Washington Sea Grant crab program.