MAINE MONITOR • March 22, 2024
About a decade ago, Blue Hill Bay mussel farmer Evan Young noticed it was getting more and more difficult to harvest mussel larvae — known as spat — needed to grow mussels. Experts believe the shortage of spat is due to warming waters and increased predation on the young shellfish due to green crabs, sea squirts and the like. The wild blue mussels population on the Maine coast has dropped 60 percent since the 1970s, according to a 2017 study. “Whether or not it’s a direct or indirect link between warming waters and mussel spat decline, I don’t think it matters,” said Brian Beals, a marine ecology professor at the University of Maine at Machias and the volunteer director of research at Downeast Institute in Beals. “If it’s direct, that means the mussels are physiologically not capable of coping with warming waters. If it’s indirect, the warming waters have caused predators to increase.”