THE PENOBSCOT UNDAMMED

Can We Restore the River to Its Natural State and Bring Back the Fish?

Alewife population is down by 70%, eels access less than 20% of their historic habitats, and American salmon and shortnose sturgeon are on the endangered list. What if 10,000 salmon migrated upriver each year instead of a few thousand seen today? Or if shad increased by a million or more? This could be a possibility when two dams along the Penobscot River are taken down beginning this year.

On Thursday, January 26, Dr. Steve Coghlan, Assistant Professor of Freshwater Fisheries Ecology at the University of Maine’s Department of Wildlife Ecology, is the featured speaker at the 2012 Ocean Environment Lecture Series: Rachel Carson Lectures, hosted by the Marine Environmental Research Institute (MERI) in Blue Hill. Coghlan’s lecture, The Penobscot Undammed: Restoring the River, begins at 7 p.m., preceded by a reception at 6 p.m. All lectures in the series are free and open to the public. MERI’s 2012 lectures celebrate the life of Rachel Carson, marine biologist, author and conservationist whose 1962 book Silent Spring galvanized public response to the dangers of pesticides and launched the global environmental movement.

Coghlan points out that many of Maine’s river ecosystems today bear little resemblance to their natural state. “Removing dams could be our last best shot at restoring the Penobscot River to historic levels and closer to a natural river system.” He says that dams break up the natural flow of a river, disrupt river ecosystems and harm wildlife through erosion, pollution and sedimentation. They also block spawning migrations of sea-run fish and disrupt the food web, which has contributed to region-wide declines in fish species and stocks.

According to Coghlan, “Sea-run fish once ranged thousands of miles inland, but their spawning habitat has been fragmented and disconnected from the main river by dams and other barriers.” The result is that Atlantic salmon, alewife, herring, sturgeon, shad and other fish are closer to disappearing from Maine’s waterways. Given that these fish constitute forage for birds, wildlife and commercial fish that support Maine fisheries, the consequences are economically and ecologically devastating.

Coghlan works on the Penobscot River Restoration Project, a collaborative partnership that is spearheading the removal of the dams. He and his team are counting and characterizing fish and other aquatic species in the 12-mile stretch of the river that will open up with the removal of the dams. He and other scientists across multiple disciplines are assessing the health of the river’s ecosystems before, during and even after the dams are removed.

Dismantling the Veazie and Great Works dams on the lower reaches of the river and building an innovative fish bypass on a third dam are expected to restore access to at least 1,000 miles of river habitat and return 11 species of sea-run fish to their historic spawning grounds. Will removing the dams restore the river to a more natural state and bring back the fish? Coghlan is optimistic. “Fish are the first to decline when you install dams, but they respond quickly once you take them out. That’s what we’re working towards.”

The Marine Environmental Research Institute, located at 55 Main Street in Blue Hill, is a nonprofit organization dedicated to protecting the marine environment and human health through scientific research and education. For more information, please call 207-374-2135, send an e-mail to info@meriresearch.org, or visit MERI online at www.meriresearch.org.