A pilot whale and her two calves escorted Cristian Vergara partway across the Strait of Gibraltar when the 46-year-old Park Slope accountant recently swam to Morocco from Spain.

Mr. Vergara, a veteran open-water swimmer who has swum around Manhattan three times (it takes him about eight-and-a-half hours) had never encountered anything like the whales.

“About three-quarters of the way across, I noticed a shadow to my left,” he explained. Because he was breathing on his right side, he didn’t immediately spot them. Rolling his head to the left on the next breath, he saw the pod about 15 feet away, swimming parallel. He could hear them communicating.

The proximity of the whales caused some concern among Mr. Vergara’s crew, including two members of the Spanish Red Cross and his wife, a psychiatrist, who spotted the mother, estimated to be 14 feet long, and her young, about half that size, swimming close.

“I didn’t get scared, as I didn’t feel threatened by them,” he said of the whales, but after keeping their distance for a couple of minutes, “they started swimming closer,” Mr. Vergara explained.

“My wife and the lifeguards on the Zodiac had been screaming at me to get out,” Mr. Vergara said. “My wife was frantic. The lead boat turned back because of the screaming,” he said. (The captain later confided to Mr. Vergara that the whales were merely curious – and harmless.)

When the whales got within six feet, he stopped swimming. As soon as he did, they submerged, not to reappear.

“It was one of the greatest experiences of my life,” Mr. Vergara said of his temporary adoption by the whale family.

Mr. Vergara’s was the 120th crossing of the Strait of Gibraltar.

Each year, “the window of opportunity is very small,” explained Mr. Vergara. “For two weeks it can be unswimmable, then you can you can have two days where you can,” he continued.

“The wind normally blows easterly; we need a westerly wind because the easterly is very strong and will push you out into the Atlantic Ocean, whereas the westerly wind is weaker, so you don’t get blown off course, Mr. Vergara said. “It blows you to Morocco,” he said.

Making the Europe-to-Africa crossing in four hours and 10 minutes (a 13-kilometer, straight-line distance), Mr. Vergara swam in 6-foot waves and refreshingly cooler water as he neared Morocco.

Although Mr. Vergara spent the earliest years of his life in Chile, the country of his birth and one with thousands of miles of coastline, he never swam in the ocean there. “The water is very cold,” he said.

In Chile he learned to swim in streams and lakes. He moved to Ohio, at age 12,and was a competitive high school swimmer, but left the sport after graduation.

Mr. Vergara resumed in 2000, because at almost 200 pounds, he wanted to lose weight. Four years later and hundreds of miles later, he weighs a slim 172 pounds, and now, ironically, wants to gain weight.

“For the Channel,” he explains, referring to the English Channel. Body fat aids flotation, making it easier to swim greater distances.

“I’m the first on the queue for the neap tide July 10, 2005,” he said of his upcoming attempt at the English Channel. “It’s the first swimmable day” of next season, he explained.

His first open-water swim, in 2001, was a one-miler on Long Island. “It was the first time I ever swam in the ocean,” he said.

“It was cold, but I made it,” he explained. “I swam the mile. The next day I did a 5K. I was seeing how far I could go. The 5K was fantastic,” he said.

On recent Saturday morning, Mr. Vergara, a quiet, direct person, stood along with five other swimmers in the Municipal Parking lot in Brighton Beach, Coney Island, getting ready for one of their three-times-a-week, four-mile swims. His close-cropped gray hair matched his silver Volvo, where he stowed his clothes.

Pulling out a container of Vaseline, he rubbed some under his arms to prevent chaffing and grabbed his goggles and red swim cap.

“I don’t know if I would have stayed in the water,” said one swimmer, Henry Eckstein, of Mr. Vergara’s encounter with the whales on his crossing.

While whales do not faze this father of three, jellyfish can.

“The jellies,” he sighed. “At Coney Island they’re big, and I do get scared of them because they sting,” he said.

He couldn’t think of anything else unusual or menacing in his swims in the rivers and ocean waters around New York. Then he remembered some striped bass off Brighton Beach.

“They were very small – around five inches- they weren’t following me,” he said. “They were following the person I was swimming with. They followed us the whole way,” he recalled.

Deep-set brown eyes offset a bright smile as Mr. Vergara walked across to the parking lot to the boardwalk, tying his car key in the string of his red nylon trunks that said “The Victor” on his right hip.

From April to November this group meets regularly at Brighton. On this October morning, a stiff wind blew and the water looked gray and choppy.

Mr. Vergara walked into the surprisingly warm water, only to run back out.

“One thing I forgot to tell you. One time coming out, I got pinched by a crab,” he said, with the enthusiasm of a child, mimicking a crab’s pincers with his fingers.

“That made me scream,” said the man who felt at home with the whales.

A jet banked as it prepared to land at JFK, and a tug pushed a freighter toward Manhattan. The green, orange, yellow, and red caps of the swimmers disappeared as they headed toward Marine Park Bridge.

Capri Djatiasmoro, on the boardwalk with her bike, told of how she once suggested to Mr. Vergara that they swim from Coney Island to Sandy Hook, seven miles away.

“I love Cristian,” said Ms. Djatiasmoro, “He’s so crazy. He said, ‘Yes, we could do that.'”