ON BARATARIA BAY, La. -- The wildlife apocalypse along the Gulf Coast that everyone has feared for weeks is fast becoming a terrible reality.

Pelicans struggle to free themselves from oil, thick as tar, that gathers in hip-deep pools, while others stretch out useless wings, feathers dripping with crude. Dead birds and dolphins wash ashore, coated in the sludge. Seashells that once glinted pearly white under the hot June sun are stained crimson.

Scenes like this played out along miles of shoreline Saturday, nearly seven weeks after a BP rig exploded and the wellhead a mile below the surface began belching millions of gallons of oil.

"These waters are my backyard, my life," said boat captain Dave Marino, a firefighter and fishing guide from Myrtle Grove. "I don't want to say heartbreaking, because that's been said. It's a nightmare. It looks like it's going to be wave after wave of it, and nobody can stop it."

The oil has steadily spread east, washing up in greater quantities in recent days, even as a cap placed by BP over the blownout well began to collect some of the escaping crude. The cap, resembling an upside-down funnel, has captured about 252,000 gallons of oil, according to Coast Guard Adm. Thad Allen, the government's point man for the crisis.

If earlier estimates are correct, that means the cap is capturing from a quarter to as much as half the oil spewing from the blowout each day. But that is a small fraction of the roughly 24 million to 47 million gallons government officials estimate have leaked into the Gulf since the April 20 explosion that killed 11 workers, making it the nation's largest oil spill ever.

Allen, who said the goal is to gradually raise the amount of the oil being captured, compared the process to stopping the flow of water from a garden hose with a finger: "You don't want to put your finger down too quickly, or let it off too quickly."

BP officials are trying to capture as much oil as possible without creating too much pressure or allowing the buildup of ice-like hydrates, which form when water and natural gas combine under high pressures and low temperatures.

In Gulf Shores, Ala., boardwalks leading to hotels were tattooed with oil from beachgoers' feet. A slick hundreds of yards long washed ashore at a state park, coating the white sand with a thick, red stew. Cleanup workers rushed to contain it in bags, but more washed in before they could remove the first wave of debris.

Alabama Gov. Bob Riley and Allen met for more than an hour Saturday in Mobile, Ala., agreeing to a new plan that would significantly increase protection on the state's coast with larger booms, beachfront barriers, skimmers and a new system to protect Perdido Bay near the Florida line.

Riley, who was angered by a Coast Guard decision to move booms from Alabama to Louisiana, said the barriers must be up within days for him to be satisfied. Allen said he needed to report to the president before confirming more details of the agreement.

The oil is showing up right at the beginning of the lucrative tourist season, and beachgoers taking to the region's beaches haven't been able to escape it.

"This makes me sick," said Rebecca Thomasson of Knoxville, Tenn., her legs and feet smeared with brown streaks of crude. "We were over in Florida earlier and it was bad there, but it was nothing like this."

At Pensacola Beach, Erin Tamber, who moved to the area from New Orleans after surviving Hurricane Katrina, inspected a beach stained orange by the retreating tide.

"I feel like I've gone from owning a piece of paradise to owning a toxic waste dump," she said.

Back in Louisiana, along the beach at Queen Bess Island, oil pooled several feet deep, trapping birds against unused containment booms. The futility of their struggle was confirmed when Joe Sartore, a National Geographic photographer, sank thigh deep in oil on nearby East Grand Terre Island and had to be pulled from the tar.

"I would have died if I would have been out here alone," he said.

After six weeks with one to four birds a day coming into Louisiana's rescue center for oiled birds at Fort Jackson, 53 arrived Thursday and an additional 13 Friday morning, with more on the way. Federal authorities say 792 dead birds, sea turtles, dolphins and other wildlife have been collected from the Gulf of Mexico and its coastline.

Yet scientists say the wildlife death toll remains relatively modest, well below the tens of thousand of birds, otters and other creatures killed after the Exxon Valdez ran aground in Alaska's Prince William Sound in 1989. The numbers have stayed comparatively low because the Deepwater Horizon rig was 50 miles off the coast and most of the oil has stayed in the open sea. The Valdez ran aground on a reef close to land, in a more enclosed setting.

Experts say the Gulf's marshes, beaches and coastal waters, which nurture a dazzling array of life, could be transformed into killing fields, though the die-off could take months or years and unfold largely out of sight. The damage could be even greater beneath the water's surface, where oil and dispersants could devastate zooplankton and tiny invertebrate communities at the base of the aquatic food chain.