Red, chartreuse, and perched delicately atop the deep green water of the Guadalupe, the Royal Wulff fly meanders downstream. It glides toward the grassy bank and then back into the deepest part of the river, like an aimless afternoon stroller in the park. It rests momentarily at the edge of a foamy back current when—slam!—five-pound line spins off my reel in a showery spray as the rainbow trout that just ate my fly darts upriver. Keeping tension on the line with my forefinger, I let the fish run while I shift my stance in the running water, bracing myself for the oncoming fight. As the trout drags my line in a taut rotating arc over the water, I pause to admire the panorama of rolling hills and cypress trees that surround me, and I remind myself just how lucky I am to be fly-fishing in Texas on a warm winter afternoon.

Every mid-December through mid-February, the Guadalupe River is stocked with rainbow trout. Located in Central Texas, near New Braunfels between San Antonio and Austin, the Guadalupe is the southernmost freshwater trout fishery in the United States. Trout, as opposed to native warm-water fish like bass and catfish, can only live in cold-water rivers and streams where the annual temperature remains below 70 degrees Fahrenheit. Because the section of the Guadalupe near the dam at Canyon Lake is always cold, it is the only stretch of water in Texas where the trout can live year-round. While a few other spots in the state may get stocked with anywhere from 1,000 to 5,000 trout a year, the Guadalupe River receives about 35,000 fish annually because the waterway can sustain them. And what visionary had the imaginative foresight to see all this potential in such a tiny stretch of Texas water?

“Actually, Lone Star beer company was the first one to stock the river,” fishing guide Alvin Dedeaux says with a laugh. “They started doing it sometime back in the seventies.” Dedeaux, a laid-back guy with dreadlocks and dark brown eyes, works at the Austin Angler and has been a Guadalupe fishing guide for more than a decade. Dedeaux recently sat down with me to talk about the trout-stocking program and its success over the years. “The river is within easy driving distance of Austin and San Antonio, and then you get the Dallas and Houston folks coming in on the weekends,” he explains. “It’s also prime time for trout in the winter because that’s when the bass fishing isn’t any good. When you put those two factors together, it makes the river a real attractive place for Texas fishermen,” Dedeaux says.

Years ago Lone Star dropped its trout-stocking program; the program was picked up by Trout Unlimited, a national nonprofit established to conserve, protect, and restore North America’s trout and salmon fisheries, along with Texas Parks and Wildlife (TPW). Trout Unlimited and TPW now stock the Guadalupe River with mostly rainbow trout, a fish chosen for its fast and aggressive nature, a trait that makes it easier to catch than other kinds of trout. Because the two organizations want to keep trout levels sustainable, fishing along the river is tightly regulated by game wardens. Due to their efficient management, Trout Unlimited and TPW have turned the Guadalupe River into one of the most reliable and well-maintained trout fisheries in the nation.

Standing in the river with my rod held high, I steadily reel my line in as the weary trout finally concedes after a four-minute fight. It struggles half-heartedly as I pull it in close, scooping it up in my wooden net. I bring out a twelve-inch rainbow, its dark-green body speckled with black spots and splashed by a faded pink streak along its side. With its colors shining in the sunlight, I admire the trout for a few seconds before gently taking the hook out of its mouth. Holding the fish with its head facing upstream so that the moving water can run through its gills, I coax the trout back and forth before it shakes its head and swims upriver again, cutting a clean line through the water at first, and eventually disappearing out of sight around a shadowy bend.

The Austin Angler, located at 312 1/2 Congress Avenue in Austin, Texas, holds free fly-fishing introduction classes twice a month and also offers full guiding services. Call 512-472-4553 or go to austinangler.com for more information.