Green crabs

The European green crab (Carcinus maenas) is one of the most successful and damaging invasive species in the world. Its recent arrival along Washington's inland shorelines poses a threat to critically important estuarine ecosystems, including native species and shellfish resources, as well as critical wildlife habitat.

Source: Washington Sea Grant

European green crab story map cover image

OVERVIEW

Story map: European green crab in Puget Sound

A broad collaboration of volunteers, agencies, and tribes are working together to keep invasive European green crabs at bay in Washington state. This story map was produced by the Encyclopedia of Puget Sound and the Puget Sound Institute in collaboration with the Washington Sea Grant Crab Team. 

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Sharon Riggs from Padilla Bay National Estuarine Research Reserve sets a Fukui trap to monitor European green crabs. Photo: Emily Grason/WSG
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Search for invasive green crab continues during pandemic

The state's stay-at-home order has halted much of the field research that would normally be underway in Puget Sound this spring, but a small group of scientists and volunteers have been able to continue their search for an invading marauder along the shoreline. Their work has been classified as critical by the state.

Image of dark blue ocean water surface overlaid with a light blue double helix graphic.
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Carcinus maenas. Photo: Brent Wilson (CC BY-NC-SA 2.0) https://www.flickr.com/photos/59048895@N06/5409329320/
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Where did the Puget Sound green crabs come from? We’re still not sure

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Carcinus maenas. Photo: Brent Wilson (CC BY-NC-SA 2.0) https://www.flickr.com/photos/59048895@N06/5409329320/
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Second invasive green crab found in Puget Sound

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A state inspector boards a container ship at the Port of Seattle to check on ballast water and determine whether procedures were followed to reduce the risk of invasive species being released into Puget Sound.  Photo: WDFW
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Carcinus maenas. Photo: Brent Wilson (CC BY-NC-SA 2.0) https://www.flickr.com/photos/59048895@N06/5409329320/
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Green crabs could impair Puget Sound shellfish operations

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A clump of cordgrass (Spartina alterniflora) Photo: USDA-NRCS PLANTS Database
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