Groundfish trawling effects on sea ecology

Working in cooperation with Maine trawler captain Cameron McLellan and the Gulf of Maine Research Institute, UMaine graduate student Emily Knight and UMaine Marine Science professor Les Watling recently completed a long-term study that examines the effects of groundfish trawling on the complex ecology of the sea floor in the Gulf of Maine.
Based on the gradual increases in complexity and diversity of seafloor communities that have been protected from bottom trawling for two, four, and six years, Watling estimates that it will take roughly a decade for the surface-dwelling organisms to reestablish themselves, but cautioned that a full recovery of the habitat would take much longer.

"I am pretty firmly convinced that if the groundfishing industry doesn't soon begin to undertake measures to conserve complex bottom habitat, there will be little chance that fishery will ever recover to levels seen 50 or 100 years ago. Small, bottom fish need complex habitat and it is clear that rock hopper gear reduces habitat complexity," said Watling. "No good habitat, hardly any fish."

The good news is that recently protected habitats are recovering. While anything resembling a "natural" condition would certainly be far in the future, Knight found that significant gains had been made in the short term.

"Scientists were predicting it would take decades for recovery, but didn't have an opportunity to look at it," said Knight. "This is the first project that has been able to look at areas closed for six years. We're already seeing signs of recovery after a significant amount of time. We're not seeing a huge trajectory change, but we can say it is recovering toward stability."