A dolphin has died after it got stranded in the Gowanus Canal in Brooklyn Friday.

The Riverhead Foundation for Marine Research and Preservation said the dolphin died before the high tide at 7:10 p.m. Marine experts had hoped the tide would help carry the animal back to sea.

Experts aim to conduct a necropsy to determine why the dolphin died, but it may well have been ill when it got into the canal, said Robert DiGiovanni, a senior biologist with the foundation, which specializes in cases involving whales, dolphins, seals and sea turtles. Staffers were having trouble getting to the dolphin's body on a snowy night.

The sea creature had bobbed up and down in the murky water for much of the afternoon and evening, the spout in its head visible each time it pushed itself above the surface. It looked to be bleeding from its dorsal fin.

While the dolphin was churning up sediment and mud, it's unclear whether that contributed to its death, DiGiovanni said.

The Northeast Regional Office of the NOAA Fisheries Service confirmed to NBC 4 New York that the creature was what's called a short-beaked common dolphin, known for its dark gray cape along its back.

Common dolphins live to be about 35 years old and are usually under 9 feet long, weighing about 440 pounds. They can be found in many parts of the world.

DiGiovanni said earlier it was unsafe to put rescuers in the water and that they were planning to wait and see if the dolphin would leave on its own when the tide rises.



"The best course of action is to see if that when the tide comes back in the animal will move back out," DiGiovanni said. "It’s giving the animal time to work the problem out before you introduce stress by intervention."

NYPD officials said the marine foundation's experts had planned to help the dolphin on Saturday morning if it didn't get out of the canal during high tide.

The dolphin, which appeared to be about 7 feet long, likely entered the canal from the Atlantic Ocean through the Lower and Upper New York Bays and then the Gowanus Bay, which leads to the canal. It's about 20 miles from the canal to open ocean.

Experts don't know why the dolphin wandered into the canal, but in general that can happen when one gets sick or disoriented, DiGiovanni said.

The Gowanus Canal empties into New York Harbor and is surrounded by Park Slope, Cobble Hill, Carroll Gardens and Red Hook. It was once a major transportation route, and numerous manufacturing facilities operated along its banks for years.

The U.S. Environmental Protection Agency calls it "one of the nation's most extensively contaminated water bodies," with pollutants including PCBs, coal tar waste and heavy metals.

It was added to the EPA's list of national Superfund priorities in 2010.

It may seem strange, but it's not uncommon for sea creatures to stray into city waters, though they don't often swim away alive.

A dolphin was found dead last August near Long Island, south of the canal. Another washed up in June in the Hudson River near Manhattan's Chelsea Piers sports complex.

In 2007, a baby minke whale that briefly captivated the city wandered into the Gowanus Bay and swam aimlessly before dying.

Two years later, a humpback whale took a tour of the city's waters before leaving New York Harbor safely. The 20-foot whale was first seen in Queens before it headed for Brooklyn, took a swing through the harbor and headed toward open waters near the Verrazano-Narrows Bridge.