News of the North- The invasive European green crab has been confirmed on beaches along the Ketchikan road system for the first time. The species was first detected in Alaska in July 2022 by the Metlakatla Indian Community on Annette Island, who have since spearheaded local and regional responses.
The green crab is considered one of the most invasive species in the marine environment. It has few predators, aggressively hunts and eats its prey, destroys seagrass, and outcompetes local species for food and habitat. It has been documented that green crab devour juvenile king crab as well as juvenile salmon. They also destroy eelgrass habitat that larval fish use to hide from predators, and outcompete Dungeness crabs for food and habitat. Green crab could potentially damage Alaska’s multi-billion dollar fisheries industries, especially for salmon, crab, and mariculture operations.
Southeast Alaska Tribal Ocean Research, Alaska Fish & Game, and Alaska Sea Grant provide public resources about European green crabs in Southeast Alaska including detection, identification, and impact information, The best way to identify green crab is to count the spines. There are 5 spines behind the eye on each side of the shell.
Green crabs live on rocky shores, cobble beaches, sandflats and tidal marshes. They can often be found near eelgrass beds or other shoreline vegetation. Green crabs tolerate a wide range of water salinity and temperature. They can also survive upstream of river mouths in some estuarine environments.
Report your sightings via the ADF&G Invasive Species Reporter or by calling the Invasive Species Hotline: (877) INVASIV ((877) 468-2748). If you locate invasive green crab on Annette Islands Reserve, you can call (907) 886-FISH to make a report.
