Collaboration with DEC Eel Study

The Department of Environmental Conservation is conducting a study of The American eel (Anguilla rostrata) at various sites along the Hudson River. They chose Groundwork Hudson Valley to coordinate a study in Yonkers, which will be the southernmost site in the study.

The American Eel is a migratory fish that is born in the Sargasso Sea, a region of the Atlantic Ocean near Bermuda, that migrates all the way to the Hudson River as tiny “glass eels” each spring and then swims up small Hudson River tributaries to mature. In the first week of the study we have found a dozen glass eels at the mouth of the Saw Mill River, an important Hudson River tributary. We are testing for eels further north in the river in Yonkers to see if they are making it beyond the mouth. The species is in decline over much of its range, making tributaries where they can safely mature very important.

This Yonkers study comes at a perfect time, before the groundbreaking for the Daylighting project, that will reveal and restore sections of the river that run underground. If the study finds that man-made obstacles are making it impossible for the small eels to get up the river, we may be able to engineer changes to accommodate them. To get involved in the study please contact Emily Ederat 914-375-2151.

Recent News: American eel—a tricky critter to accommodate in Yonkers Daylighting!
Who’d have thought that the American eel could reach 7 ½ miles up the Saw Mill River ABOVE the Woodlands Lake dam with everything it has to go through now—entering the river underneath the train station, swimming under Larkin Plaza for 1 mile in the dark, then up over a flow station, through concrete channels, and up a 20-foot dam! Studies completed by Robert Schmidt of Hudsonia for the Saw Mill River Coalition (a program of Groundwork Hudson Valley) in the spring of 2008 found the American eel—ABOVE THE DAM! These creatures slithered up vegetation to make beyond the dam.

The tricky part now for the eel with the Yonkers’ daylighting project, is to be sure that when engineers bring two new sections of river back to the daylight, their design will allow species of fish to make it upstream, and down again. This will impact the American eel, and other migratory species, possibly the alewife (herring). Coming down the river is as important as going upriver because the adult American eels, after about 5 years growing in tributaries, come back down river, into the Hudson and out to the Atlantic to swim to the Saragossa Sea to spawn. Ensuring a healthy eel population means being sure both routes—up and down—“work” when you re-engineer a new river path.

To that end, Groundwork Hudson Valley is working directly with the City of Yonkers, bringing fish expertise to the problem. As part of a New York/New Jersey Harbor Estuary Program Grant, Groundwork Hudson Valley has a fish passage expert and a habitat consultant working directly with the engineers. One section of the river that will be exposed in Larkin Plaza will be turned into a public park, raising the concern of how to prevent “floatable” trash from coming through the park after a storm. A trash netting chamber is being designed, and the fish passage expert is working with the engineers to be sure the fish species in the tributary will be able to pass up and down, through and around the netting chamber and not be caught in it.

One exciting part of the river park design will be a fish ladder, called an Alaska steep-pass, that will be visible to the public as it assists the fish in making it up the slope in Larkin Plaza. This will be a terrific teaching opportunity in our new river park! The engineering plans should be set soon and the City is hoping to begin construction of this wonderful new park sometime in 2010! For additional information, please email: