For many anglers, the pinnacle of fly fishing is casting a dry fly to a rising trout as it feeds on hatching insects. And truly, very little gets the blood racing like seeing a fish slash at your drifting dry fly. But reverence for this classic scenario has led a lot of fly folk to assume that using dry flies is like getting out the good silverware—something reserved for special occasions.
In fact, dry-fly fishing is a lot more versatile and simpler than you might think, and most of the rules are actually more like suggestions. So, if you want to catch more fish on dry flies, these are the rules to bend—or just plain break.
Rule to Break: Matching the Hatch
Fly fishing’s best known and probably greatest wisdom is to match the hatch by using imitations that resemble the fish’s natural foods. But this mantra is best when loosely followed. You don’t need to know Latin names of bugs, or take a butterfly net to the river. Although trout can sometimes key in on specific foods while ignoring others, this tendency has been vastly overstated in fly-fishing lore. Never forget that trout are, like most gamefish, enthusiastic, opportunistic predators.
Even if you identify boysenberry-coloured sub-variant Tyrannosaurus oedipus mayflies in the air, that might not be what a rising fish is actually eating. In lab experiments, for example, wild trout have been found to remember a specific food for about three weeks. A simple, effective strategy, therefore, is to match the hatch by using a fly roughly similar to what’s in the river—or what was in there recently.
Where I live, that means I follow a seasonal pattern of generally imitative dry flies, starting with mayflies earlier in the year, followed by caddisflies of decreasing size and, come July, hopper patterns. The bottom line is, some bug knowledge is good, but too much can lead you into the weeds.
Rule to Break: Casting to Rising Fish
Somewhere along the way, it became conventional wisdom that fly anglers should only fish dries when fish are rising. No one told the trout that, however. In fact, prospecting, or blind casting, with a dry fly can be very effective when the fish aren’t rising.
I discovered this technique one sunny summer afternoon about 10 years ago while working a stretch of riffly, thigh-deep pocket water. Though no fish or insect activity was apparent, I knew it held trout, so I tried to fish it—and none too skilfully—with weighted nymphs. Unable to get a good drift and sick of hang-ups, I finally decided to just enjoy my casting, even if it meant getting skunked. I tied on a size 14 Henryville Special caddis dry fly and lofted it up and across the river. To my immense surprise, it got hit on the first drift. Then I pulled about eight more fish out of that riffle.
Not long after that, I read The Orvis Guide to Prospecting for Trout by Tom Rosenbauer and discovered my experience was no fluke. In his essential book, Rosenbauer describes a wide set of conditions when prospecting with a dry fly can be effective. Since then, I’ve dared to blind-cast dry flies from late spring through to autumn, and at least 70 per cent of the trout (and smallmouth bass) I’ve caught on top came when there was no surface activity. Broadly speaking, you can fish dries effectively any time fish are likely to be oriented upward for food—that is, they’ve been feeding on top sometime in the prior few weeks—in water that’s relatively clear, not super-fast and above 15°C.
The other consideration is that you’ve got to provide a meal tantalizing enough to make it worthwhile for a fish to come to the surface. So, a rule of thumb is to use flies on the hefty size, and keep scaling up as the water gets deeper and faster. By arming yourself with a modest arsenal of generically buggy-looking dry flies in a variety of sizes, you’ll be well equipped to fish—and catch—on top this trout season.
Associate Editor Scott Gardner often tackles the fly fishing world’s sacred cows.
Have you ever tried drifting a wet fly around submerged brush or behind a fallen log? Since subsurface flies need time and space to sink before they become effective, getting one into the strike zone around such cover can be extremely challenging. So instead, try dropping in a dry fly, which becomes effective the moment it lands.