For the first time in over a century, American shad (Alosa sapidissima) have been discovered upstream from the former Columbia Dam site on the 42-mile long Paulins Kill river, an important tributary to the Delaware River in northwestern New Jersey.
Princeton Hydro’s Senior Water Resources Engineer and avid fisherman, Dr. Clay Emerson, PE, CFM, caught an American Shad in the Paulins Kill miles above the previous dam site this past weekend. (Above photo courtesy of Princeton Hydro.)
A successful collaboration between The Nature Conservancy, American Rivers, Princeton Hydro, U.S. Fish and Wildlife Service, and NJDEP Division of Fish and Wildlife resulted in removal of the out-of-commission hydroelectric Columbia Dam just months ago.
Prior to this removal, American Shad and other migratory fish could not make it past the large dam structure to swim upstream to their important breeding grounds.
The American shad’s return is an excellent sign of the overall ecological health and diversity of the river. Historically, dams, overfishing, and pollution have caused population decline in many of the major eastern U.S. rivers. American Shad, deemed the “Mid-Atlantic salmon,” are anadromous, which means they spend much of their lives in the ocean but returnto rivers and their tributaries to spawn.
This long distance swimmer makes it one of the Earth's great travelers. Afterspawning upstream in rivers of the East Coast, American Shad migrate to their primary habitat in the Atlantic Ocean up in the Gulf of Maine.
Unlike the salmon of the Pacific Ocean, American shad may return to their spawning grounds multiple times over their lifetime.
The species is a key prey species for many large fish and cetaceans like dolphins and whales in the Atlantic Ocean.
“The best indicator of river water quality improving in the Paulins Kill is the appearance of shad miles upstream from the Columbia Dam,” said Dr. Barbara Brummer, New Jersey State Director of The Nature Conservancy.
“Today [Monday], we celebrate proof that with the 100-year dam impediment removed, they are once again successfully swimming up the river. I could not be happier! This is what teamwork and passion for nature can achieve. It is a great day for conservation in New Jersey, with many more great days for shad in the Paulins Kill to come.”