DEAN WILSON ONCE SURVIVED TARZAN-LIKE in Louisiana's Atchafalaya Basin for four months eating "horrible-tasting" ratty nutria and "fat and juicy" armadillos that he killed with a straightened fishhook. But now it's Sunday night on State Highway 1 in darkened bayou-burbia, and we need pizza. 

"I don't know that we'll find anything at this time of night in Plaquemine," Wilson says, surveying the familiar commercial clutter of Family Dollars and auto parts joints. "Maybe we should go back home and have deer burgers." The nationally acclaimed swamp crusader clearly would prefer to be cruising the languid Atchafalaya Basin behind the wheel of his 18-foot aluminum bateau or whipping his kayak through the watery cypress forests he has spent years trying to protect from loggers.

Wilson's environmental epiphany came when he realized that cypress trees were being logged not for lumber but for garden mulch. | Photo by Christian Heeb/Prisma/SuperStock

Born to an American father and a Spanish mother on a military base outside Madrid, Wilson came with little English to the sweltering Atchafalaya Basin in 1984 to prepare himself for environmental work in the Amazon. "I just looked at a map and thought this place would be very hot and have lots of mosquitoes," he recalls. "I was right." 

Wilson decided that Louisiana life suited him just fine, so he skipped the Amazon and stayed to become a commercial fisherman. For the next 16 years, the Spaniard learned the customs of his neighbors and picked up an intriguing but not always decipherable Cajun-Castilian accent. When he was just "the new foreigner," he received threats from locals, especially after he worked with a sheriff to stop the theft of crawfish traps. A "friendly" local told Wilson not to worry, that he probably wouldn't be killed because, the local said, "your skin is white and your eyes are right"—meaning not Mexican, not Vietnamese. The threats intensified after he became known primarily as an environmentalist: He was fired at, and his dog was poisoned. 

"I still sleep with a gun," says Wilson, who likes to hunt, but only for food. "Guns have saved my life down here. I told one guy who threatened to burn me out of my house that he wasn't the only person who knew how to make a fire."

As a fisherman, Wilson witnessed industrial pollution, illegal logging, and the dredging of oil company canals throughout the basin. He thought that complaining to the proper authorities might help. "I was really naive," he says. "Coming from Spain, I had no idea how corrupt Louisiana politics was." His environmental epiphany came around 2000, when he realized that Louisiana loggers were harvesting thousands of acres of cypress trees—not for home building or flooring, as in years past, but to supply the flourishing $750 million annual market for garden mulch. 

"That was the last straw for me," Wilson says, "knowing that people were clearcutting trees that were often centuries old in order to grow flowers in their garden."

WE SLIP KAYAKS INTO PEACEFUL Grassy Lake behind Wilson's simple home on Bayou Sorrel to survey the bald cypresses that have brought so much purpose to his life. You can almost feel his stress dissolving with each paddle stroke. "It gets a bit shallow up through here," Wilson hollers as he leads me into a watery forest draped in Spanish moss. He splashes into the muck with his knee-high rubber boots, and we tug the kayaks through soft grasses until we reach a deeper pool that's surrounded by smooth bald cypresses.

The Atchafalaya's iconic alligator shares space with 60 species of reptiles and amphibians and some 250 bird species in America's largest river swamp.| Photo by Adam Jones/Visuals Unlimited

"Almost the entire Gulf Coast, and certainly all of Louisiana's coast, was once covered with these wonderful trees," he says. "Only they were much taller, four or five times wider, and many were over a thousand years old. They say it better than I can. This is why I'm here." 

It's a shame that movies and books often portray the cypress as a foreboding, mossy ghoul of the swamp, because it's among the most trouble-free, wildlife-friendly trees on the planet, and a close relative to California's Disney-darling sequoia. Since its branches grow out perpendicularto its trunk, the cypress is a great tree for nestingwaders like herons, egrets, and ibis. The hollowed-out trunks of older cypress become perfect homes for raccoon, otters, mink, bears, bats, and owls. 

The massive root system of the cypress also makes it among the most hurricane-resistant of all trees.

The cypress decimation started long ago. In 1850, Congress passed the Swampland Act, deeding millions of acres of wetlands to the states along the Mississippi River. Louisiana officials, like others, viewed swamps as an impediment to progress and sold thousands of acres containing virgin cypresses to large corporations, often for 75 cents an acre or less.

"Instead of controlling floods in the Atchafalaya," write basin scholars Greg Guirard and C. Ray Brassieur in their 2007 book Inherit the Atchafalaya, "the Swampland Act enabled the complete devastation of one of the world's great forests." In the early 1900s, timber companies logged millions of board feet from the basin annually, usually by cutting canals (some still in use today) and floating the logs off to the mill. By the 1930s, most of the virgin trees were logged. Nearly a century later, about the only large cypresses left in the basin have been struck by lightning or a fungus. 

Realizing he was witness to the last of the swamp's cypresses, Wilson formed a nonprofit called Atchafalaya Basinkeeper—one of about 200 programs affiliated with Waterkeeper Alliance, a global organization founded by activist Robert F. Kennedy Jr.—and began using litigation and public education campaigns to protect the basin. 

Wilson won support from such groups as the Sierra Club, the Garden Club of America, the National Audubon Society, and the Louisiana Environmental Action Network. Some days he prodded understaffed, poorly funded investigators in the New Orleans EPA office to better police the Gulf. On others he talked to schoolkids.

Often Wilson's only legal toehold against the logging is to use the federal Clean Water Act to pursue companies that build unpermitted roads in the forest. Wilson says he's also gotten "crucial" help in doing aerial surveillance of the logging from SouthWings, a group of volunteer pilots based in Asheville, North Carolina, who monitor activities like pollution from animal feedlots and illegal coal-ash disposal. "SouthWings made the difference," he says, "between losing trees and saving trees." 

Wilson's greatest success in the anti-mulch campaign came when Home Depot, Walmart, and Lowe's agreed in 2008 to stop selling mulch harvested from Louisiana cypresses. The news is comforting as we drift silently among the stately trees, but Wilson quickly puts it in perspective. "That's just one state," he says. "Loggers will move to Mississippi, Georgia, Florida." 

If treehugging doesn't work, Wilson can also argue pure profit. "If you cut every cypress in Louisiana," he says, citing a Louisiana study commissioned in 2004 by then-governor Kathleen Blanco, "its one-time value as wood alone would be about $3.3 billion, but the total annual value of swamp tours, birding, fisheries, hunting, hurricane protection is more like $6.6 billion." 

With the help of the Tulane Environmental Law Clinic, Basinkeeper currently has seven lawsuits going—most involving permitting issues—against foes like Tennessee loggers, school districts, and energy companies whose environmental practices have somehow impacted the basin. For now, he simply implores consumers not to buy cypress mulch from any source. 

Back at Wilson's bayou-side house, he sits on a porch swing and whips out his laptop. He shows me surveillance photos tracking cypresses being logged from the Atchafalaya Basin, cut at local mills, "chipped" into mulch, and then stuffed into yellow plastic bags with labels that falsely claim the mulch has come from Florida or "forest-friendly" sources. Wilson has shown the photos to countless people, but he's careful not to demand outrage from the uninitiated. Still, he's dismayed that his smoking gun hasn't inspired more official action. 

"It is immoral to lie to people about what you're selling," he says calmly. "Virtually everything we do comes down to corporations bullying people. I hate bullying. I hate injustice." 

That's the Dean Wilson everyone knows. While a forestry association official once dismissed him as "all passion and no facts," colleagues respect his abundant idealism and his hard work. Thick EPA studies, brightly colored satellite maps, and hydrology reports dot his living room. A network of activists keeps his cellphone humming. "Dean does this every day, from the time he wakes up until the time he goes to sleep," says friend and Lafayette environmental educator Stacey Scarce. It's all necessary in a place where logging ancient trees is just one environmental threat, a place where the oil, gas, and chemical industries not only affect the Atchafalaya but also run right through it.

IN EARLY-RISING PLAQUEMINE, my Best Western breakfast nook features more petroleum mechanics and burly welders than blueberry muffins. 

State Highway 1, a flat and sweaty industrial corridor that runs south from Baton Rouge to the Gulf of Mexico, is choked with pipe fitters and laborers headed to this area's largest employer, Dow Chemical, on the west bank of the Mississippi. There, more than 3,000 workers churn out polyethylene and methyl cellulose, key ingredients in milk jugs and even milkshakes. 

In the shadow of Dow, a shimmering steel monument to the dirty industries that shape so many lives down here, it is easy to forget that just a few miles away is a world-class wetland. Wilson, who also runs the Last Wilderness, a swamp-tour business that attracts visitors from as far away as France and Germany, has told me to meet him at the Bayou Bait Shop in Bayou Sorrel. The village of 1,000 looks like a fishing camp; wobbly wooden homes beside the brown bayou are raised up on concrete piers. The straight two-lane road into town passes the U-turn-inducing Verret Shipyard, where they've been making Mississippi River towboats since 1966. Homemade signs tout "fresh coon meat" and Ron Paul rallies. 

"Hey, Dean," a lady behind the bait shop counter says, "you know Junior's back in town, and he's got some new T-shirts." 

That would be the town's unassuming but unfathomably famous celebrity, Junior Edwards, the gator-gutting star of the History Channel's hit reality show Swamp People, which has brought international exposure to the basin and its slowly disappearing Cajun culture. 
Wilson and I walk to a little dock on the eastern edge of the Atchafalaya. From that vantage point, it's hard to imagine the extent of the basin, which is 1.4 million acres, runs about 100 miles north to south, and is more than a dozen times larger than New Orleans. It's the flood basin for the Atchafalaya River, a "pirate stream," or distributary, that broke through the natural levees of the Mississippi in the 15th century—and has threatened to divert the latter river's flow ever since. 

Zippered against the wind in Wilson's boat, we rocket down the Gulf Intracoastal Waterway as Shanka, his German shepherd, patrols the squared-off bow. It's warm for January but winter nonetheless, so many of the swamp's most elegant creatures, like the Florida panther, the black bear, and the mink, are snoozing. But birds are everywhere. The basin is virtually at the mouth of the Mississippi, on North America's most important flyway, and is an indispensable, O'Hare-like terminal for migratory tropical birds. Two minutes into the boat ride we see a stunning bald eagle—removed from the federal endangered species list just five years ago—unfurl from a willow perch as if it has fallen from Mt. Rushmore. Ten more minutes and we've seen great egrets, yellow-rumped warblers, Carolina chickadees, and stocky barred owls with NBA wingspans. Missing are the swamp's divas, Alligator mississipiensis. They're brumating, which usually involves burrowing beneath the nutrient-rich sediment into muddy holes and lowering their body temperature to a torpid, football-watching state. 

Amid all this tranquility, we pass a docked barge carrying black tanks of chemicals, a quick reminder that the basin, while elegant in places, is just another aging production field for Big Oil, woven with miles of exposed, often-leaking, 50-year-old pipelines and more than 500 oil and gas wells. "We've got leaks all over the basin," Mike Bienvenu, president of the Louisiana Crawfish Producers Association, recently told the Louisiana Weekly. "We've been fighting the oil and gas companies to get something done about their violations for 20 years." 

Wilson checks some of his crawfish traps—mesh metal cages that he pulls from the cool freshwater—then idles into a shallow, moss-covered pool. Pretty but depressing, the water's surface is so completely carpeted by the leafy, invasive Salvinia molesta that dogs less hip than Shanka will often leap in, thinking it's dry land—unwisely waking torpid gators. 

"In the spring, if I were to drop just a handful of Salvinia into clear water," Wilson says, "it would be covered solid in a month." Experts believe the menace arrived here in 2006 from local water gardens. 

At times Wilson, a father of four on his third marriage, may seem wearied by the day-to-day demands of fundraising, lawsuits, and not missing his son's soccer games. But surrounded by this bright morning theater of cypress, he can't help being drawn back to what brought him here. "Imagine if millions of cypress, four or five times as wide as these, had been lining the Gulf Coast in 2005 when Katrina and Rita struck," he says. "They would have defeated the wind. They would have defeated storm surges. They would have saved lives."