Richard Drew / AP
An injured dolphin surfaces in the Gowanus Canal in the Brooklyn borough of New York, on Jan. 25.
An injured dolphin that became stranded in Brooklyn's Gowanus Canal died Friday, a marine foundation said.
The Riverhead Foundation confirmed to NBC News the dolphin passed away Friday evening. No other details about the mammal's death were immediately available.
Earlier Friday, live helicopter video from NBCNewYork.com showed the sea mammal bobbing up and down in the canal's murky water — which the U.S. Environmental Protection Agency declared a Superfund site in 2010 because it contained a "century's worth" of pollutants.
The dolphin appeared to be stuck in one section of the canal, coming up occasionally for air as a New York Police Department crew worked to figure out a rescue plan. It was unclear how the creature got into the predicament. The NYPD told NBC News the dolphin was stuck in the vicinity of Union Street, between Bond Street and Nevins Street, which is at least a mile into the canal and away from the Gowanus Bay.
Authorities were hoping the dolphin would be able to escape by itself during the Friday evening high tide, but if not, were planning on helping it out on Saturday, police told The Associated Press.
A senior biologist at the Riverhead Foundation told NBCNewYork.com rescuers were waiting to see if the dolphin would leave on its own: "The best course of action is to see if that when the tide comes back in the animal will move back out," Robert DiGiovanni told NBCNewYork.com. "It’s giving the animal time to work the problem out before you introduce stress by intervention."
The Northeast Regional Office of the NOAA Fisheries Service confirmed to NBCNewYork.com this mammal was a short-beaked common dolphin, which is known for a dark gray cape on its back.
Witnesses had said the animal appeared to be bleeding from its dorsal fin, the New York Daily News reported.
"He keeps going up and down and going from side to side and people are saying we don’t know what’s taking so long to go in there and save him," Brooklyn resident Cathy Ryan told the Daily News. "He’s in bad shape. You can tell. A dolphin is gray, but he's black right now. He was starting to swim toward the middle of the canal. But it doesn't look good."
Michael Heiman / Getty Images
Officials stand on the side of the Gowanus Canal as the dolphin comes up for air after getting stuck on Jan. 25, in the Brooklyn.
Eight-year-old Anabell Blaine told NBCNewYork.com she had hoped they got the dolphin out: "Dolphins are so beautiful."
The Gowanus Canal is in Brooklyn, flanked by the Park Slope, Cobble Hill, Carroll Gardens and Red Hook neighborhoods, according to NBCNewYork.com. It empties into New York Harbor.
The Environmental Protection Agency says storm water runoff, sewer outflows and industrial pollutants have made it one of the most extensively contaminated water bodies in the U.S.
Manufactured gas plants, mills, tanneries and chemical plants are among the many facilities that operated along the canal, according to the EPA.
The EPA said the contamination in the canal poses a threat to the nearby residents who use the canal for fishing and recreation.
Bystander Vinny Internicola told the Daily News on Friday he can smell the water from his vantage point: "I can’t imagine being in there."
A day earlier, a WNBC news helicopter spotted a minke whale swimming in Gowanus Bay.
NBCNewYork.com's Gus Rosendale contributed to this story.
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