Shad, Dams, and Beer
More than 70 people learned about the American shad at a Chester Ridley Crum Watersheds Association Science on Tap event on February 20 at waR3house3. Photo: Susan Ethridge
When The New York Times published an article last week about an extensive dam-removal project on the Brandywine River, some Swarthmoreans were already familiar with the plan. They were the 80 or so folks who attended Science on Tap at waR3house3 on February 20. Science on Tap is an annual speaker-and-beer event sponsored by the Chester Ridley Crum Watersheds Association (CRC). This year’s speaker was Jim Shanahan, co-director of Brandywine Shad 2020, the organization spearheading the dam-removal project.
“Shad was a staple in the diets of Native Americans and early settlers,” Shanahan said. “But starting about 300 years ago, dams were built on the river to power grist mills and divert water for towns. Migratory fish populations, like the American shad, were destroyed.” Shanahan and his colleagues at Brandywine Shad 2020 are removing (or in some cases modifying) 11 dams along a 25-mile stretch of the Brandywine River over the next three years.
Shad spend most of their lives at sea but swim back upstream to spawn in freshwater. And they are relentless. “Now that Dam 1 is gone, we expect to see the shad breaking their noses against Dam 2,” joked Shanahan. More than just shad are expected to return to the Brandywine. Bald eagles and other wildlife that prey on migratory fish should also return to the watershed.
Shanahan entertained the audience with stories about the Dam 1 removal process and outlined the challenges the group expects to face as they remove Dams 3, 4, 6, and 11 this year.
