ADRE ISLAND NATIONAL SEASHORE, Tex. — Eyeballing a fish supper at 30 miles an hour, the brown pelican flew just six inches above the surf. Suddenly, it made nearly a 90-degree dive and crashed into shallow, churning water.
"You'd think they'd break their neck, but they never do," said Johnny D. French, a retired biologist for the United States Fish and Wildlife Service who has been living, working and driving up and down this beach for most of his 56 years.
Until the pelican stopped so abruptly for a meal, it and the biologist had been traveling companions here on the longest, at 113 miles, barrier island in the United States. The pelican was riding the wind. In a parallel lane about 20 feet inland, Mr. French was driving on hard-packed sand in his sport utility vehicle.
The brief joint journey of the endangered brown pelican and the S.U.V.-encased biologist gets at the mushy meaning of the word "pristine," which is used — often with far more emotion than precision — to describe America's national parks, including this splendid stretch of sand off the Gulf Coast of Texas.
Padre Island National Seashore is not at all pristine, nor is it a good test case for those who would draw absolute lines in the sand about what should and should not be allowed in a national park. This park is a heavily traveled, natural-gas-producing wedge of sand that happens to be a terrific place to rescue endangered birds and turtles.
Padre Island can, of course, seem pristine. Great blue herons wade in the surf, stabbing mullet with their stiletto beaks. About half a million hawks, falcons and other birds of prey feast here in the fall on migrating songbirds. The brown pelican is one of 11 endangered species making a comeback on the park's 80-mile beach.
Yet tens of thousands of four-wheel-drive rigs prowl every year along that beach, which under Texas law is a public highway. Out in the gulf, the horizon is punctuated by giant offshore drilling platforms. Six gas and oil pipelines are threaded beneath Padre Island, tying together 60 gas wells (almost all of them now dormant) dug here in the last half-century.
Then there is the natural gas drilling approved this year by the Bush administration. Together with the drilling of an exploratory gas well last spring, a Nov. 8 decision by the National Park Service to allow two more wells has infuriated environmental groups.
They point to Park Service documents that describe how the drilling of as many as 18 gas wells in the next 30 years could bring 20 heavy trucks a day to this beach.
When Congress created this park 40 years ago, it made a point of allowing oil and gas drilling. Since then, though, Padre Island has consistently defied all-or-nothing arguments about land use, whether from outraged environmentalists or hard-line advocates of energy exploration.
Since the Park Service decided to allow new gas drilling here, the most serious environmental complaint — and the focus of an unresolved lawsuit by the Sierra Club — has been the harm that could be done to the world's smallest and most endangered sea turtle, the Kemp's ridley.
This beach is the primary American nesting ground for the turtles and the focus of a major federal effort to save them. The park service is allowing big trucks carrying drilling equipment to drive on the beach during the spring and summer turtle nesting season.
Environmentalists say that 18-wheelers will leave damaging ruts in the sand and may crush the turtles or smash the eggs they bury in shallow holes on the beach. But opponents of gas drilling tend not to mention the 800,000 tourists who drive this beach every year, many of them in turtle nesting season.
In fact, the federal effort to save the Kemp's ridley has prospered in the last 20 years despite sharp increases in tourism and S.U.V. traffic. Park workers have enlisted the drivers to help spot nesting turtles when they emerge from the surf. The 90-pound turtles are easily seen from a moving vehicle.
Once the turtles are spotted, park workers rush out to protect nesting turtles and collect their eggs. The eggs are taken to a sheltered beach, where they are incubated and newborn turtles are escorted to the sea. The program has increased the number of Kemp's ridley nests in the park to a record 23 this year, from zero in the mid-1980's.
Truck drivers in the gas drilling operation were trained this year by park officials to spot and brake for the turtles. The first nesting Kemp's ridley of the season was found with the help of a truck driver.
"Joe Six-Pack does not have the turtle awareness training of our drivers," says H. Scott Taylor, executive vice president for BNP Petroleum, which is drilling in the park.
Still, champions of drilling on Padre Island are hardly immune from making misleading overstatement.
Going after natural gas in this national park, Mr. Taylor contends, is a normal activity that Texans "expect to see in their future." Similarly, the Interior Department, which oversees the national parks, has contended that nothing out of the ordinary is going on here.
"There is nothing new here, and what is new is better," Eric Ruff, spokesman for Interior Secretary Gale A. Norton, said recently.
These statements, however, do not square with the historical pattern of gas exploration on Padre Island. As tourism has soared in the last two decades, and as Park Service biologists have spent thousands of hours improving habitat for endangered birds and turtles, gas drilling has declined sharply. Just two wells were dug in the 1990's, both dry holes. Only two wells are producing gas in the park, one of them dug this year.
Johnny French, the retired biologist who was traveling on the beach with the brown pelican, said Padre Island would be well served if everyone who cares about the park reined in rhetoric with fact.