If you stop 10 random citizens on the busy streets of Baltimore and ask them who Lefty Kreh is, chances are pretty certain that 10 out of 10 will reply, "Who...?" Ask someone fly fishing on a remote river miles from any other human being, and it's 100 percent the opposite: "Lefty Kreh is a god." (Direct quote from my friend Mike, the most obsessed fly fisherman I know.)

Bernard "Lefty" Kreh, Maryland native and longtime Baltimore Sun outdoor editor, literally wrote the book on saltwater fly fishing: First published in 1974, Fly Fishing in Salt Water revolutionized the devoutly traditional art of fishing with the long rod. Kreh is renowned worldwide for his skill as both a fisherman and a teacher. His radical approach to fly casting-for example, throwing out the time-honored wisdom of "clock face" casting (the rod tip should only ever travel between 10 and 2 on an imaginary clock), and proclaiming that the elbow can actually move instead of being anchored in one place-originally caused a great deal of outrage in the fly fishing world. "I was censured pretty badly for taking the rod past 2 o'clock," he says, "Hell, clocks are for keeping time, not for fishing." Kreh seems to have thrived on the controversy; he went on to produce 30 more books, numerous instructional DVDs, and radio and television shows. He has also instructed countless eager students in his own original casting style, based on "Lefty's Five Principles."

Kreh was also a visionary in expanding fly fishing from A River Runs Through It trout streams to the open seas. He first picked up a fly rod in 1947, working the waters around his native Frederick, and purchased his first fly rod and reel at Tochterman's Fishing Tackle on Eastern Avenue, a long hike from Frederick in those days, but it was the only place around that sold the obscure gear. Kreh saw no reason to give up fly fishing when he moved south in 1964 to work as a writer at various Florida newspapers. "People thought saltwater fish were too big and too fast to catch with a fly rod, but I proved that wrong pretty quick," says Kreh, who can point as evidence to the 100-pound tarpon, caught during his first year in Florida, mounted on his living room wall. He still lives in the same tidy Cockeysville home he's occupied since returning to the Baltimore area in 1972 to take a job with The Sun-first with his family, then just his wife, Evelyn, until she died in 2011, and now by himself -when he's home, anyway. Now, at a robust and active 88 years old, Kreh's peripatetic professional life keeps him on the move between speaking engagements, filming still more instructional DVDs and cable fishing programs, and just plain going fishing all over the world.

Kreh, despite his nickname, is an ambidextrous angler. He's in great demand as a fishing instructor and guide, and he's wet a line with two presidents, as well as (legend has it) Ernest Hemingway. He does not, however, take himself or his fame particularly seriously. Perhaps his experiences during World War II (he was at the Battle of the Bulge, helped liberate concentration camps, and earned five battle stars) make all others seem relatively tame. Two years ago, the Maryland Department of Natural Resources commemorated the fly-casting icon by naming a state park trail along the Gunpowder Falls, a nationally recognized trout stream, in his honor. Kreh didn't really want the honor, having fought off a previous attempt to name a lake in Frederick County after him, but says he agreed to the Gunpowder trail in hopes of promoting conservation.

Conservation is his prime concern these days, and Lefty Kreh's ambition for his remaining days is "to make sure there are some darned fish left for our grandkids to catch." Fish populations are declining worldwide, and he is using the bully pulpit of his fishing fame to inspire action. He helped found a nonprofit research organization called the Bonefish Tarpon Trust to fund the study of saltwater game fish populations; closer to home, he campaigns for better land and water management to protect local waterways. Kreh says that Marylanders are failing to connect rampant development with its effect on our state's natural resources. For instance, he says, intense development around Frederick has lowered the local water table to the point where "all the feeder streams off the Monocacy River where I used to seine baitfish when I was young are dried up. Gone. You can't even tell they were there." He also decries the state of the Susquehanna, pointing out that it's one of the most polluted rivers in the country. "Nobody's too worried yet because you can still catch some really big bass in the Susquehanna," he says. "But what scares the hell outta me is that you can't catch any little ones. They're not there. When you don't have the next generation coming behind, you're in big trouble."

Kreh doesn't often fish around this area anymore, in part due to environmental degradation-"The fish are just gone," he says flatly-and in part because, even after 65 years, he is still in love with the challenge of saltwater fishing. His favorite destination is anywhere notoriously spooky, difficult-to-catch bonefish can be stalked. "When you first start fishing, you want to catch a lot of fish, and then you want to catch big fish," he says. "But [when] you've been at it as long as I have, you want to catch the hard fish."

Wherever Kreh goes fishing, though, he's sure to be recognized. And for those lucky enough to run into him, the chance meeting will offer more than a brief encounter with a fly-fishing legend. Instead, it will very likely turn into an impromptu casting lesson as the master angler with the twinkling blue eyes and generous smile turns another stranger into an instant friend. Welcome to the Cult of Lefty.