Dead Dolphin Found in Hudson River at Chelsea Piers, N.Y.C. A dead dolphin was found Thursday morning in the Hudson River at Chelsea Piers - several days after an offshore bottlenose dolphin, a species rarely seen this close to land, was spotted swimming in the Hudson off Manhattan. The dead dolphin was found floating near Pier 59, at the end of 18th Street, around 6 a.m., said Erica Schietinger, a spokeswoman for Chelsea Piers, the athletic complex. Chelsea Piers" staff secured the animal and called the police. Kimberly Durham, a biologist with the Riverhead Foundation, a rescue group, said the foundation had dispatched a recovery team from its base on Long Island. "Our plan is to recover the carcass and conduct a necropsy on the animal to determine cause of death," she said. It was too soon to know if it is the same dolphin spotted in Chelsea and Harlem on Sunday and Tuesday. Ms. Schietinger said the floating docks at Chelsea Piers attract a lot of river debris. "The security guys regularly call people when we find things in the Hudson," she said.