The dog days of summer can wreck a trout fisherman. The heat is brutal, the water is low, and the big hatches are mostly long past. Worst of all—fish can turn seriously sluggish. But, by following a few simple, surefire fly-fishing rules, you can turn what would otherwise be an unproductive day into one for the books—while other anglers head home empty-handed.
It’s All About Oxygen
Trout, like people, need oxygen. So, in summer, avoid broad stretches of flat water, since they’re usually less oxygenated than streams or rivers with lots of riffles and rapids. Look for surface chop, plunge pools, and whitewater, and then dead-drift your flies along slow edges and seams. Once you hook up, play the fish quickly and then release it without removing it from the river, since trout mortality goes way up in the summer.
When the temperature spikes, you can find some of the best summer fishing at high elevations, so don’t hesitate to make a long uphill hike. Headwater creeks and streams tend to stay cool and productive despite the blistering heat, and mountain lakes also come alive as afternoon winds drop ants, beetles, and grasshoppers on the surface. Come prepared with a handful of terrestrial patterns and streamers, like a Woolly Bugger, size 6 or 8, in black, brown, or olive.
If you don’t have access to high-mountain streams or lakes, tailwaters—rivers that flow out of man-made impoundments—make for good bets, too, since the water that runs from the bottom of reservoirs is cold, and usually full of trout. If you don’t see rising fish, try casting a parachute Adams (size 14, 16, or 18) on the surface. If that doesn’t work, swing a small black leech fly (size 8 or 10) or dead-drift scuds and small pheasant-tail nymphs (size 16 or 18) under an indicator.
There’s nothing wrong with occasionally throwing large flies, like a hopper, golden stone, or Woolly Bugger. But late summer is prime time for busting out small patterns, like ants, beetles, mayflies, and caddis. Tie them on with 5X or 6X tippet, then target shady areas, riffles, and undercut banks, and minimize false casts, to avoid spooking fish.
Rise and Grind
Warm water turns trout lazy. Since daybreak is the coolest time of day, set your alarm clock early and take advantage of the prime, early-morning water temps, when trout will be most active. At sunup, you’re also more likely to see rising fish, since summer hatches and spinner-falls usually wrap up before lunchtime.
Todd Tanner, a former fishing guide and longtime outdoors writer, lives in Montana, where he heads School of Trout, a fly-fishing program for aspiring anglers, now accepting students.