April 2, 2007 (Vol. 5, No. 5)
More Herring Released into the Bronx River
Dr. Joseph Rachlin (Biological Sciences) and his team from Lehman's Laboratory for Marine and Estuarine Research (LaMER) returned to the Bronx Zoo on April 5 to help release 400 alewife herring into the Bronx River. The goal of the project—being carried out with the New York City Department of Parks and Recreation's Natural Resource Group (NRG)—is to establish a breeding population of these native fish in one of the nation's most urbanized waterways. The Bronx River is the only remaining free-flowing river within New York City's borders.
Alewife herring, native to New York City waterways, vanished from the Bronx River as early as the 1600s when dams built by Dutch settlers blocked access to spawning grounds. Like salmon, river herring hatch in freshwater and swim out to sea, returning as adults to spawn. Alewives are important food items for gamefish, such as striped bass and bluefish, and for herons and ospreys.
Biologists from Lehman and NRG will monitor the herring over the coming weeks to determine whether they have successfully spawned. It is expected that juvenile alewives will migrate to Long Island Sound and other coastal waters, and return to the Bronx River as adults in three-to-five years.
Last spring, the LaMER team helped to successfully introduce 200 herring into the river. Biologists believe that reintroduction of the alewives will encourage biodiversity by drawing more predatory fish upstream into the estuary, and attracting more birds throughout the system. Establishing a run of herring will also increase fishing and other recreational opportunities and encourage a sense of stewardship toward the long-neglected river.
The alewives were collected from Bride's Brook in East Lyme, Connecticut, and transported by truck by Connecticut's Department of Environmental Conservation's Inland Fisheries Division. They were released via chute into the river.
The project is funded by a federal partnership grant to the Wildlife Conservation Society (the Bronx Zoo's parent organization) from the National Oceanic and Atmospheric Administration. The grant was secured by Congressman José E. Serrano.