HAVANA — Australian endurance swimmer Chloe McCardel ended her attempt to swim from Cuba to Florida after 11 hours in the water when she was stung by a jellyfish Wednesday night.
It was the fifth failure involving three women swimmers who have tried to make the marathon swim since 2011. Jellyfish stings and strong currents have been the main impediments.
Her support team released a statement saying that McCardel stopped her effort to become the first person to swim across the Straits of Florida nonstop without a shark cage "due to a severe debilitating jellyfish sting."
It said she had been taken on to one of her support vessels and was sailing to Key West. She would need 24 hours to recuperate, it said.
Bob Olin, skipper of the primary support boat, the Sunluver, said McCardel had suffered multiple stings.
"She got nailed all over her body — back, legs and arms. Nailed multiple times, all at the same time," he told The Associated Press by satellite phone.
He said the team tried to treat her wounds while she remained in the water, but had to take her on board a boat because she was suffering "excruciating pain."
The swimmer had not said much since leaving the water, Olin said.
Diana Nyad, an endurance athlete who failed three times to make the same crossing and has said she'd like to take another shot this summer, tweeted her commiseration.
"It's a tough night for Chloe McCardel, a superior swimmer and an exemplary spirit," Nyad wrote.
McCardel, a 28-year-old from Melbourne, had hoped to complete the swim in about 60 hours.
Before starting out from Cuba in the morning, a smiling, upbeat McCardel had arrived in a pink 1950s Chevy convertible at a rocky jetty in western Havana
"As confident as I can be. I think it's all going to work out well," she said of her chances. "It'll be tough, though."
McCardel then jumped feet first into the water at 10 a.m. sharp.
Her goal, the Florida Keys, lay a little more than 100 miles (160 kilometers) to the northeast of Havana.
The sea off Havana was flat and glassy, precisely the ideal conditions that McCardel's science team had forecast.
The strait has been busy the last three summers, with fellow marathon swimmers Nyad and Penny Palfrey making four failed attempts at the crossing between them since 2011.
Australian Susie Maroney successfully made the swim in 1997, although she did it with the benefit of a shark cage.