Presence of invasive sea squirts increasing as Gulf of Maine warms

MAINE PUBLIC • December 5, 2025

Squishy, blobby and alien-looking, some varieties of sea squirts — so called because they squirt water when they’re disturbed — have been in Maine for hundreds of years. But with the Gulf of Maine warming rapidly due to climate change, it has created a more hospitable habitat for new hangers-on from elsewhere: invasive sea squirts. For those who work in aquaculture, these invaders can be a constant source of annoyance and stress throughout the fishing and growing season. And some years, they can be a major hindrance to doing business.