A sperm whale that was drifting off an eastern Florida shore on Sunday has died, according to the National Oceanic and Atmospheric Administration.

The agency now plans to look into a report from a resident of Pompano Beach, north of Fort Lauderdale, who said she saw the whale alive earlier in the day and saw one of two swimmers get on top of the whale, NOAA said. 

"This whale was likely ill or injured and that is why it came in so close to shore," said Blair Mase, NOAA's southeast regional stranding coordinator. "This type of harassment could have caused more harm and added stress to an already stressed whale and ultimately caused its demise."

It is a federal offense to harass a marine mammal, Mase said.

"People need to be aware that they shouldn't do that," she said.

Sperm whales, the largest of the toothed whales, also are an endangered species, she said.

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Marine scientist Stefan Harzen said it's possible a boat struck the whale or something simply made the whale sick.

"There's really very little you can do for a whale if it gets seriously ill or injured," he said.

On its 'last leg'
The witness, Margie Casey, 49, told NBC 6 that she saw two swimmers twice go up to the whale Sunday morning. She said she watched them from her fifth-floor balcony and snapped photos of one swimmer getting on the whale.

Casey said the whale at the time was drifting north along the shore, just south of a stretch of beach near the Northeast 14th Street Causeway.

Casey said she considered the whale to be alive, because it was flapping its tail at the time. Perhaps the whale was on its "last leg," she said. "So sad."

About 11:45 a.m., bystanders reported the whale was about 40 feet from the shore, according to sheriff's spokeswoman Veda Coleman-Wright.

A marine mammal rescue team, the Broward Sheriff's Office and the Florida Fish and Wildlife Conservation Commission responded.

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Before it was announced the whale had died, beachgoers said they hoped the whale would survive.

"I think it's totally amazing, man," said Brad Schwab. "It looks like they're trying to keep him out in the open sea."

Beachgoer Dennis Cooper added, "I guess everybody's concerned about the health of the whale and everybody's trying to save it."

Christina Coniglio, who was also on the beach, said she suspected that pollution contributed to the whale's illness.

"The environment is so dirty," she said. "When the whales go and eat all those plastics and bottles and things we throw in the sea, they get sick and this is what happens."

The whale had been coming close to shore while rip currents kept pulling it back out, Coleman-Wright said. When officials arrived, a specialist went into the water and determined the species that died was a sperm whale, Mase said.

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