From the Magazine

Eels Get a Leg Up Over Dams

Helping eels slide past dams with some PVC pipe and netting.

Chris bowser feels affection for fish. Well, one in particular: the American eel. “People just think they’re these slimy little creatures that live in the mud,” says Bowser, an Audubon TogetherGreen 2009 Fellow and 2011 Innovation Grant recipient. “They’re one of the most mysterious animals on earth.”

In just four decades some populations of this species have declined by 90 percent. Bowser’s work—through TogetherGreen and as a science educator and estuary researcher—focuses specifically on bringing the fish back to the Hudson River watershed.

For several years he has led hundreds of volunteers in what he calls citizen stewardship (a step beyond citizen science)—all in the name of eels. High school students, among other participants, assess the eels’ health by weighing and monitoring them. On top of that, his team is using several eel ladders to allow the fish to reach habitat critical to their growth.

Eels are not only accessible and great for environmental education, they’re also pretty awesome, Bowser notes. The fish crystalize the connection between watersheds and oceans that often goes unnoticed, he says. Born in the ocean, they spend at least their first year in the salty water before swimming into freshwater streams up and down the eastern seaboard. Dams, however, can stop their upstream migration.

To assist the eels on their journey, the volunteers help set up a big net-filled PVC pipe, which leads eels into a water-filled bucket. Hoses, held in place by sandbags, pump water into the pipe. At least twice a week volunteers check the bucket, measure and count the eels, and release them—far past the obstruction. During a six-month pilot project, Bowser’s group assisted nearly 1,500 eels.

Without the young fish, estuary ecosystems lose a crucial food source; without the adults, humans lose a key environmental barometer. “What you have is a long-lived animal that eats high on the food chain,” Bowser says. “If you want to look at what kinds of toxins, what kinds of organic pollutants are in your ecosystem, you go to the eel. It’s a filter that might live decades.” If successful, the eel ladders will give the fish a fin up, he adds, alleviating at least one environmental stressor and making long life a reality.


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