Potential Marine Invaders Identification

Marine Introduced Species Monitoring Resource Center

Prevention and early eradication of marine biological invaders are the most effective methods of managing nonindigenous species. Therefore, we are asking the people who live, work, and play along the coastline to be on on the watch for new arrivals. We want you to become the eyes on the water. SSCW has created ID cards for seven species that have the potential to invade the New England region.

Early detection efforts are most concerned with these “Potential Invaders”. If you believe you have seen one of them, it is important to notify your monitoring organization, the MarineID aand/or Hitchhiker Sighting Submission Form immediately.

When a "Potential Invader" is found, volunteer monitors will need to have the sighting verified. Careful note of its location, a photograph, and/or a specimen sample should be taken. MIT Sea Grant under its Hitchhiker's Guide Program has developed excellent verification instructions. A taxonomic expert will then confirm the sighting.

Potential Invader Identification Cards

Synidotea laevidorsalis
Asian isopod


Eriocheir sinensis
Chinese mitten crab

Drawing - Rob Gough

Corella eumyota

Photo - Gretchen Lambert

Rapana venosa
rapa whelk

Drawing - Rob Gough

Undaria pinnatifida PDF=1.8MB
undaria kelp, wakame seaweed

Photo - Steve Lonhart
Monterey Bay NMS

Sargassum muticum PDF=1.2MB
Japanese seaweed, wireweed

Photo - Kevin Briton-Simmons

Hemigrapsus takanoi PDF=1.9MB
brush-clawed shore crab

Photo - Adriaan Gittenberger

Invaders in New England
13 ID Cards


Scientific Books and Papers

Additional Web Site Links

Monitoring Methods/Data Sharing


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Since 1991


Salem Sound

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Suite 9
Salem, MA 01970

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