FREEPORT, Maine — This time last year, Brunswick Marine Resources Officer Dan Devereaux pulled back a clump of mud along the banks of Harpswell Cove and revealed a swarm of green crabs frenetically scurrying for cover.
But when Devereaux dug a clam rake into the mud in Buttermilk Cove on Friday, he found only a few scattered mussels. Nearby, a cylindrical trap that last summer was teeming with the invasive crustaceans now holds only a single, native crab.
So far this season, the European green crabs that for the last couple of years decimated lucrative clam flats in Casco Bay have not appeared.
Researchers aren’t sure why — one theory is that unseasonably cold water has kept the crabs at bay — but they are trying to find out, while hoping that the crab infestation wasn’t just delayed this year by the length of time it took for coastal waters to warm.