Walden – Like commuters meeting the morning train, they came rolling in, right on time.
A lake virtually deserted minutes earlier suddenly teemed with activity. Kick boats of every size and shape appeared from vehicles like rabbits from a magician’s cape. Flailing at mosquitoes, other anglers waded deep enough in the chilly water to risk at least temporary harm to certain parts of their anatomy. Someone even launched what looked like a small yacht.
Each knew precisely why, and when, he had come. Another callibaetis hatch was about to begin.
For the stillwater fly enthusiast – or anyone who enjoys watching larger trout make fools of themselves – this emergence of large mayflies is the signal event of the summer season.
From the early part of mid-June until deep into August, these insects tantalize trout, and the anglers who seek them, with their Baryshnikov dance. Depending on elevation and weather, the action begins between 10 and 11 a.m. and lasts about three hours, give or take.
It’s the ultimate gentleman’s hatch. Sleep late. Take a nice breakfast. Extra cup of coffee, unless you plan on an extended session in a kick boat. Play tug of war with a couple dozen nice trout. Back in town for a leisurely late lunch. Bottle of wine if you have a really nice fish to celebrate.
The object of all this attention is a lake or pond-dwelling mayfly, light in color and large enough to be imitated on a No. 16 hook. This insect spends its formative months along the bottom in soft soil. This elongated nymph features an extensive array of gills along its body, essential in gaining oxygen from calm water.
Most anglers approach the callibaetis hatch from two directions, up and down. The lower action starts first, with a nymph dangled strategically above the bottom vegetation, generally in 8 to 10 feet of water.
As the insects begin to stir toward their ephemeral life’s mission of emergence and propagation, trout cruise the carpet moss for the appetizers. The main course is announced, not by a flourish, but a solitary slurp as the first trout tracks an insect to the surface.
What happens next is determined by temperature, wind, cloud cover and vagaries that hardly anyone can understand.
Last week at South Delaney Butte Lake west of Walden, in sunshine and dead calm, passengers arrived promptly at 10 a.m. Trout gulped mayflies confidently and a happy shout announced an angler’s first success.
When it seemed as if the action should reach its crescendo, everything stopped. Slender, graceful insects still fluttered above the surface. But feeding activity abruptly went off track and for several minutes stayed that way.
A visitor scheduled for an afternoon engagement on a nearby stream foolishly mistook this for an ending, paddled to shore, unstrung his rod and watched in amazement as the whole show started all over again. As he drove away, gazing sadly over his shoulder, rise rings covered the lake.
For many anglers, the callibaetis hatch can be a time of frustration fraught with difficulties choosing the proper fly in competition with so many naturals. For this, we offer a simple, and single solution: The Gilled Nymph.
This pattern devised years ago by Thornton tying whiz Shane Stalcup represents an all-in-one answer to the callibaetis puzzle. Stalcup uses singed ostrich herl to imitate the pronounced gill structure that gives this fly its distinction. He details the pattern, and the theory behind it, in his exceptional 2002 book, “Mayflies Top to Bottom.”
It can be used as a nymph along the bottom, a tactic favored by Aurora resident Herman deGala on Quincy Reservoir and other area lakes, or on the surface.
“It’s the fly I use 95 percent of the time at Quincy,” said deGala, who makes daily trout catches well up in the dozens.
DeGala concedes that much of the magic rests with the fly rather than the angler.
“I give it to guys who aren’t catching much of anything and they start hauling them in,” he said.
For those who prefer action on the surface, grease the Gilled Nymph to sit in the surface film. You’ll catch more fish than on a dry imitation, gain the same visual satisfaction and escape the worry of keeping your fly completely dry.
The callibaetis express will be arriving like clockwork over the next few weeks at a station near you. All aboard.
Charlie Meyers can be reached at 303-820-1609 or cmeyers@denverpost.com.
