LOS ANGELES, CA (Catholic Online) - Officials were counting on a high tide would help the dolphin leave the canal Friday night. But the animal was confirmed dead shortly before then, the Riverhead Foundation for Marine Research and Preservation reported.

Freezing temperatures coupled with thick pollution, the seven-foot-long short-beaked common dolphin made its way almost two miles inland to the end of the waterway. The dolphin struggled for air as onlookers and authorities lined the canal.

Senior biologist at the Riverhead Foundation Robert DiGiovanni said "Unfortunately, all we can do is watch and wait for the tide to rise, so the animal can get out on its own. It's not safe for us to get people in the water," DiGiovanni told reporters.

News reports showed it mired in thick black toxic sludge and authorities said the animal was injured and bleeding from its dorsal fin. Onlookers took cell photos while a news helicopter hovered overhead.

"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," a witness said.

"He's in bad shape. You can tell. A dolphin is grey, but he's black right now. He was starting to swim toward the middle of the canal. But it doesn't look good."

Animal experts waited to see if the dolphin would "free itself" from the area during the evening's high tide.

"Because there is no shoreline or easy way to get to the dolphin, investigators will only monitor it," DiGiovanni, told CNN. "It's very uncommon for a dolphin or any marine animal to be in the Gowanus, but it's happened before."

In 2007, a baby whale died after wandering up the Gowanus Canal and becoming stranded. The minke whale, about a year old, had been too young to survive on its own.

In that instance, experts had reported seeing nothing to indicate the mammal was sick, such as swimming erratically or in tight circles. With only the whale's dorsal fin visible, observers could only guess whether it might have been injured.

As it had been in the case of the dolphin, marine biologists expressed hope earlier that the whale would find its way back into open water in New York harbor. The situation took a turn for the worse when the whale's swimming patterns changed.

There are many theories as to why dolphins get themselves stranded in shallow or narrow bodies of water. Some scientists theorize it may happen due to illness or injury, swimming in close to shore to take refuge in shallow water and getting trapped by the changing tide.

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