Dark rain clouds hang over Biloxi's white sand beach as three children search the shore for tar patties from the BP oil spill.

They come back to their parents with nothing to show for their efforts but a few shells.

"This is a real nice place," their father Mario Arce says as he looks around the nearly empty beach close to the city's signature cast iron lighthouse.

"I feel for the owners of businesses like this," the Texan says of the nearby jet ski and beach umbrella rental shack. "They expected to make money from the tourists."

Jet skis rent here for 65 dollars (51 euro) for 30 minutes and 120 dollars an hour. That is less than half what they would cost in Florida, attendant Jerry Johnson tells a prospective customer.

Last summer most people would have lined up for the privilege. But there are not many customers these days.

"This time last year this place would have been packed," Johnson tells AFP. "You see now there ain't hardly no one out here."

Nearly three months after a deadly explosion on the BP-leased Deepwater Horizon set off the worst accidental oil spill in history, Mississippi's beaches remain relatively untouched by the estimated 2.1 to 4.1 million barrels of crude that have gushed into the Gulf of Mexico.

The oil is generally washing up here in small patties that could be picked up more easily with a plastic beach spade than the heavy metal shovels used by the yellow-vested clean-up crews patrolling the shores.

It is worse after a storm but on this sweltering hot Saturday, in what should be the height of the summer tourism season, the tar patties are nearly as hard to find as the sunbathers.

"The worst way it's hurting the tourism industry is the misconception that my beach is covered in oil," says David Mason, who manages the oceanfront Snapper's Seafood restaurant.

Snapper's reopened last summer after the old building was destroyed in 2005 by the deadly Hurricane Katrina, which left few buildings and lives in Biloxi unscathed.

There are just six servers at Snapper's this summer and they are pulling in about half as much in tips as they did last year when twice as many servers were on staff.

BP removed a loose-fitting cap on Saturday and hopes a new containment system that will capture all of the oil will be operational in the coming days.

But it could still be months -- if not years -- before the oil patties stop washing up on shore and Mason is worried that he soon will not have any oysters or local shrimp to serve his customers.

It has been weeks since commercial or recreational fishing has been allowed in this part of the Gulf and people here are much more concerned about long-term seafood safety after traces of oil were discovered this month in crab larvae.

While charter boat captains and fishermen are in desperate straights and many smaller hotels have seen their bookings cut in half, so far the casinos have not seen a drop in gaming revenues.

A steady stream of people wander past the memorabilia lining the halls of the beachfront Hard Rock Hotel as they make their way to the smoky casino floor to try their luck on the colorful slot machines and the sleek blackjack and poker tables.

The neighboring Beau Rivage resort and casino is equally busy on Saturday night, with the line to get into the buffet snaking down the air-conditioned promenade while smartly dressed couples sip wine in the restaurants.

But with the number of inquiries about future bookings dropping steadily, city officials are worried that the relentless national news coverage of the oil spill will undermine the recovery efforts.

"Perception is our biggest enemy right now," says Vincent Creel, public affairs manager for the city of Biloxi.

"There's still a number of things to do here but the rest of the country sees this on TV and they think we're ankle deep in oil."

The most unnerving thing to deal with, though, is the uncertainty.

"We're used to dealing with things like hurricanes and tropical storms where they have a beginning and a middle and an end," Creel tells AFP.

"This has no ending. It's a new oil spill every day. BP can clean it up and then it's back the next day."