A green crab is held by Coffin as he scours the Harraseeket River in search of the invasive species.

Green crabs sit in a bucket after being hauled in the Harraseeket River in Freeport by Chad Coffin and Sara Randall of the Downeast Institute, aboard the R/V Green Crab 1. They were catching the crabs as part of the Freeport Clam Experiment, which is under the guidance of Brian Beal of the University of Maine at Machias.

Green crabs sit in a bucket after being hauled in the Harraseeket River in Freeport by Chad Coffin and Sara Randall of the Downeast Institute, aboard the R/V Green Crab 1. They were catching the crabs as part of the Freeport Clam Experiment, which is under the guidance of Brian Beal of the University of Maine at Machias.

Coffin throws back a common crab in his pursuit to catch and document the invasive European Green Crab.