Rescuers endured a fourth night of an anxious search for two young Floridians born and bred as boaters who vanished on the high seas.

The Coast Guard scoured an area the size of West Virginia with no sign of the boaters by early Tuesday. The 14-year-old boys' vessel was found capsized two days earlier. But relatives and friends of the teens were clinging to hope that the expertise they acquired boating and fishing in their short lives was enough to keep them alive while apparently lost in the Atlantic.

"This isn't something that he's new at," said Carly Black, the mother of Austin Stephanos, in an interview with television station WPBF. "I think they feel better on the boat than they do on land."

The mother said she wouldn't even "bat an eye" about the boys' ability to survive at sea.

Nick Korniloff, stepfather of the other teen, Perry Cohen, said the boys had been "raised on the water," knew how to navigate safely, and were more passionate about the sea than anything else.

"If you put two pretty girls in front of them and two fishing rods, they'd grab the fishing rods first," the stepfather said.

The ordeal began as a teenage summer adventure: The boys were last seen Friday afternoon buying $110 worth of fuel near Jupiter and were believed to have been heading toward the Bahamas. Thunderstorms and heavy rains were forecast in the Jupiter area later Friday afternoon. However, Coast Guard Capt. Mark Fedor called it "typical South Florida weather" that didn't provide an immediate answer to what happened to the teens.

The Coast Guard was alerted at 5 p.m. that the boys were overdue, and the search began. The 19-foot boat was found Sunday, capsized, off Ponce Inlet, more than 180 miles north of where the boys started their journey. The search has continued, day and night, with areas of concentration moving based on the Gulf Stream and ocean conditions. Coast Guard officials have most recently been focusing on waters off northeast Florida and said they had no intention of quitting yet.

"Our intentions are to continue to search aggressively," Fedor said Monday evening, adding that the decision is being reevaluated daily. Earlier Monday, Coast Guard Petty Officer Steve Lehmann said the search was going on under "the highest level of optimism." He declined to say how long it would continue. Searchers were using helicopter, boat and airplane, and local authorities and the USS Carney also joined the efforts to locate the boys.

"We need every clue and we need everyone's help," Korniloff said.

The teens' families pledged a $100,000 reward in the search and a famous neighbor -- NFL Hall of Famer Joe Namath -- promised to continue searching local beaches in hopes of finding clues.

"It's a lot of water out there," Namath said. "We just keep on looking till we get an answer."

Though the boys' boat was overturned it did not appear damaged. No foul play was suspected. One life jacket was found near the boat, though it was unclear how many life jackets had been on board.

Water temperatures were warm and not cited as a factor in the boys' survival.

Florida requires minors to have boating safety instruction in order to operate a boat of 10 horsepower or greater, but no licenses are issued. It was not immediately clear whether the boys had undergone a safety class. Korniloff said he was focused on finding the boys and wouldn't comment on questions about whether 14-year-olds should be allowed to venture so far alone.

Still, Lehmann said boaters of any age and experience level could encounter danger.

"Regardless of how experienced you are in the water, things can happen," he said. "Things befall even the most surefooted of mariners."