Like most fly fishermen, I keep a mental list of my desert island flies, the bugs I must have in my box to ensure that I’ll catch fish on every trip. Parachute Adams, Elk Hair Caddis, Hare’s Ear, Renegade, San Juan Worm, and Pat’s Rubberlegs (affectionately known as “the Turd”): these are the flies that account for almost all of my fish. If nothing else, knowing I’ve tried each one of them is a handy excuse in the event I get skunked; at least then I’ll be able to lie to myself that my poor performance is the trout’s fault and not mine.

Any experienced angler will correctly note that I left out the Wooly Bugger, which is famous for catching any type of fish in any place under any conditions. Made of soft flowing materials that move naturally in the water, the Bugger owes its deadliness to its versatility. In brown, it resembles a stonefly or a crayfish. In olive or gray, it fools fish feeding on dragonfly, damselfly, or cranefly larvae, baby crayfish, rainbow trou,t and other minnows. Go out to the Rio without a black Wooly Bugger, and you may as well go fishing without clothes on.

Anglers who make their own flies should be happy to know that you can dress up a Bugger any way you like, varying hook size, body, tail and hackle color, weight, and sparkle. The most popular New Mexico variation is the Pistol Pete, which sports a twirling brass propeller in front. A standard Alaska version, the Egg Sucking Leach, has a ball of pink chenille at the head.

The Camo Bugger is my favorite. With a peacock body, brown hackle, and multicolored tail, the Camo seemingly resembles nothing in nature, which means it could probably pass for anything. All I can say is that fish think it’s food. In the Rio near Pilar, smallmouth bass can’t leave it alone. Landing it within a couple inches—not ten inches, but two inches—from bankside boulders is the key. Same with brown trout on the Conejos in October. The Camo even scores on the San Juan, whose infamously picky fish will break from their tiny fly diets to give it a solid whack.

There are infinite ways to fish a Wooly Bugger. Cast upstream, down, or across, and retrieve it with short or long strips. Or fish it upstream and dead drift it through the pockets, remembering to allow your Bugger to swing out at the end of the drift, as fish may rush it before it escapes. If you’re fishing a lake and the Bugger’s not working, remember that lake fish feed most efficiently by patrolling the shoreline. So cast parallel to the shore and around structures where insects, as well as the little things that eat them, are most active. In saltwater, tie your Buggers on stainless steel hooks. Ocean fish are bigger and stronger than trout. Stainless hooks won’t rust or break under stress.

Understand that the only wrong way to fish a Wooly Bugger is to not fish one. Or to fish one on too light a leader. This fly is so tantalizing that it’s not only a top choice of anglers, but of big fish everywhere.