Invasive European Green Crab Verified in Ketchikan, Alaska
Date of Press Release: June 17, 2025
(Ketchikan, Alaska) - The University of Alaska Southeast-Ketchikan Campus (UAS-K) reports the verified expansion of the invasive European green crab (Carcinus maenas) in Alaska waters. UAS-K, Ketchikan Indian Community (KIC), and Alaska Department of Fish and Game (ADF&G) personnel collected two invasive European green crab (EGC) molted carapaces on the shores of Refuge Cove State Park in Ketchikan on June 6, 2025. They are the first evidence of European Green crabs found on any of the beaches on the Ketchikan road system.
The crabs were found while engaging in shoreline carapace surveys as part of a week-long community education class offered by UAS professors Charmaine Lewis and Barbara Morgan and funded by the Alaska Climate Adaptation Science Center (AK CASC). The carapace surveys were conducted under an ADF&G aquatic resources permit, as required by ADF&G.
“This was not the beach I expected to find them on,” said Morgan. “I was expecting to find them in areas that are estuaries, so that was a surprise. The expectation is that the European Green Crab population will continue to spread north, as they are pushed in the currents while in their free-swimming larval stage.”
The green crab is considered one of the most invasive species in the marine environment. European Green Crabs are voracious predators, consuming a wide variety of marine life including juvenile salmon, shellfish and native crab species, and could potentially impact Alaska’s fishing industry. In addition they destroy eelgrass beds which serve as important habitat for other species.
The public is asked to help by reporting possible invasive European Green Crabs observations. Green crabs live on rocky shores, cobble beaches, sandflats and tidal marshes. Visit the ADF&G website for information about how to identify these invasive crabs.
If you find a crab or crab shell you suspect to be a EGC, collect it and take it to your nearest ADF&G office or take photos of the crab or carapace next to a key, coin or credit card for a size reference. Do not kill any crab you find that happens to be green, many native species can also be green!
Banned invasive species, including EGC, may be collected, possessed or transported only for the purpose of reporting. Shoreline carapace surveys, may be conducted under the ADF&G blanket EGC carapace permit. To report your observations, call the Invasive Species Hotline: 1-877-INVASIV or use our reporter. To submit photos and for more information about invasive species, contact: Tammy Davis, ADF&G Invasive Species Program coordinator: tammy.davis@