Today, NYC Parks, the Bronx River Alliance, the Wildlife Conservation Society and the Connecticut Department of Energy and Environmental Protection (CT DEEP) came together to stock the Bronx River with 400 alewife, a type of river herring. The restocking is part of an ongoing effort to re-establish a population of these native fish in one of the nation’s most urbanized waterways. CT DEEP trapped and transported the fish from Connecticut to the Bronx via a dedicated Fish Tank-er trunk, releasing the fish into the river through a large hose.

“These herring are now o-FISH-ally New Yorkers,” said NYC Parks Commissioner Mitchell J. Silver, FAICP. “Like all newcomers, I know they will learn to love their new city. Our hope is that they will attract other species of wildlife, increasing the overall health of the river. Bronxites deserve a healthy river where they can learn about and enjoy nature.”

Alewife are an important food source for larger fish, birds and other wildlife in our ocean, estuaries and rivers. Stocking alewife in the Bronx River will provide the species as a whole with additional habitat and increase local biodiversity. Watch NYC Parks’ live broadcast of the release here.

"The return of alewife herring to the river will re-establish a critical link in the river's ecosystem, enabling species that depend on these fish to rebound as well,” said Bronx River Alliance Executive Director Maggie Greenfield. “A restored river is also good for the Bronx communities it surrounds. As we learn about this slice of nature that flows through the heart of the Bronx, we are inspired by its beauty and the life it supports. This, in turn, motivates us to take action to keep our parks, rivers and neighborhoods clean and beautiful."

“The return of fish such as the alewife and American eels to the Bronx River helps to re-establish connections between freshwater rivers and the marine environment,” said Dr. Merry Camhi, Director of WCS’s New York Seascape Program. “Rebuilding these fish populations in New York City can help restore and maintain ecological health needed by wildlife and people alike.”

“Spawning runs of Alewife have been important components of both freshwater and saltwater ecosystems throughout the Northeast,” said Steve Gephard, CT DEEP Supervising Fisheries Biologist. “Many streams, like the Bronx River, lost their runs when dams were built and blocked the spawning migrations.  It is exciting that work is underway to restore the Alewife run to the Bronx River.  Connecticut has been working to restore runs in its rivers and Long Island Sound, which it shares with New York.  Transplanting Alewives from one stream to another has proven effective in jump-starting restoration efforts and Connecticut is proud to be able to help bring fish into the Bronx River.

Alewife populations are declining throughout the northeast due to factors including pollution, poor fisheries management and barriers to migration—such as the 182nd Street Dam. In 2015, NYC Parks’ constructed a fish ladder over the 182nd Dam to allow fish to migrate upstream to spawn. This ladder gives fish access to 12 acres of freshwater habitat that have been blocked for centuries and allows them to pass from river to ocean.

As adults, Alewife live in the ocean and travel upstream into freshwater streams, rivers and lakes to spawn. After adults spawn in the spring, they leave the freshwater within weeks and return to the ocean. The freshly spawned eggs hatch into larvae and develop into juvenile fish that stay in freshwater to feed and grow for 1-4 months. By mid-fall, the juveniles migrate to the ocean where they remain for 3-5 years until they have reached reproductive maturity.

Hundreds of years of urbanization have subjected the Bronx River to illegal sewer outfalls, dumping, loss of native vegetation, hardened banks and floatable garbage and spills. Over the last decade, regulatory changes and community activism has led to a significant improvement in water quality. The efforts of NYC Parks and the Bronx River Alliance to restore native vegetation, control invasive plants, secure stable points of access and safe vistas of the river have helped rehabilitate this waterway. Later this year, the Bronx River Alliance will open River House—a new headquarters in Starlight Park—which will also serve as a boat house and nature classroom.

New Yorkers can volunteer with the Bronx River Alliance to help clean up and restore the city’s only freshwater river. Weekly volunteer events give New Yorkers the chance to put on waders and collect floatable trash or test water quality. For a full list of volunteer events, click here.