The Bronx got a lot more crowded on April 20, as 400 alewife herring from Connecticut commuted down from the suburbs and were released into the Bronx River from its shores in the Bronx Zoo.
The city Department of Parks and Recreation, the Wildlife Conservation Society, the Bronx River Alliance, and the Connecticut Department of Energy and Environmental Protection have been working together in an effort to replenish the alewife herring population in the river, which runs the length of the borough down to the Long Island Sound at Hunts Point. Last week’s event was the the first effort to bring the fish back to the Bronx, where they once thrived in less polluted waters.
“Their populations were so great that they used to turn some of the streams silver,” said Marit Larson, chief of natural resources for the Parks Department.
Maggie Scott Greenfield, executive director for the Bronx River Alliance and Bronx River Administrator for the city, said fish such as the alewife herring, along with beavers and oysters, were once plentiful in New York Harbor and attracted the Native American Lenape people as well as the Europeans. But over time, industrialization and development killed off many of those species. In the river, the construction of dams for industry made it impossible for fish to swim upstream, where alewife herring go to breed.
To help the fish go upstream, the Parks Department and the alliance built a fish passage — a tunnel with metal grates on top, positioned at an “angled slope” on the side of the dam.
The River Park Fish Passage at the 182nd Street Dam was a $1.87 million endeavor that was funded and supported by a consortium of non-profit conservation groups and federal, state and local environmental agencies. Merry Camhi, director of the Wildlife Conservation Society’s New York Seascape, described the building of the fish passages as “years of hard work.”
But that hard work has paid off.
“This past weekend, for the first time, we’ve documented on record that alewife are using this fish passage that we built just for them,” said Larson.
The release of the alewife herring is not only for their repopulation, it is also for building a diverse ecosystem. Striped bass will eat the herring, along with birds of prey such as osprey and even bald eagles.
“When you bring back one species it helps to rebuild the really complex food web for the river,” said Greenfield.
And no need to worry about the fish being from out of town, Steve Gephard, a fisheries biologist from the Connecticut Department of Energy & Environmental Protection assured everyone, “We guarantee you that our fish will get along with your fish just fine.