It isn’t necessarily carved in stone that the meek shall inherit. But, in the case of a certain tiny insect, it certainly can cause a lot of commotion.
You’ll find this occurrence on display at rivers all across the Colorado high country, where an emergence of miniature mayflies has touched off what may be the most dynamic surface fly-fishing event of the season.
This little bit of a bug is the baetis, better known and loved by its descriptive name, the Blue-Winged Olive or, for simplification, BWO. The beauty of the baetis is in its punch, the sheer strength to endure a cold weather lifestyle where other mayflies cannot survive.
In doing so, it serves a serendipitous function both for hungry trout and eager anglers. The season’s first significant dry fly event features the perfect insect for Colorado, where higher elevation and a plenitude of tailwaters demands a bug tough enough to take the chill. This tough little bug also has the punch to produce two separate broods each year; rare among mayflies, it yields a second hatch almost precisely six months later, in late September and October — just in case we didn’t have enough fun first time around.
While the BWO forms a prominent event on many streams throughout the region, nowhere does it create such a stir as on the Arkansas River from Cañon City upstream to Granite. Through a quirk of water conditions, the current hatch offers the best potential in years. To optimize survival of brown trout fry just emerging from gravel, the Bureau of Reclamation has trimmed the flow of water moving through the Frying Pan-Arkansas diversion system. The diminished, warmer flow will hype the hatch while making fishing easier.
“We’ve got the perfect temperature for the bugs, now all we need is cloudy weather for the prime hatches,” said Bill Edrington, who operates the Royal Gorge Anglers shop in Cañon City (719-269-3474).
While the Arkansas is more famous for its dramatic and volatile caddis hatch, the really smart set knows the most consistent action comes from the BWO.
“I rather enjoy seeing those noses coming out of the water to take the little mayflies,” Edrington said. “It’s all very delicate, almost like casting to a metronome.”
At the moment, it’s also highly predictable. With flows measuring a calm 300 cubic feet per second at Wellsville, insects have spread out across the river, a bounty both to fish and fishermen.
Greg Felt of Salida-based Arkansas River Fly Shop (719-539-3474) adds a separate perspective.
“When you half the flow, you not only cut the depth, but the volume as well. The fish spread out, creating a better dry fly situation,” Felt said. “Fish are everywhere and wading is much easier.”
Nor should anglers neglect the BWOs once the caddis get cranking in a week or two.
“When you get a little cloud cover and a rising fish refuses your caddis, better try a BWO,” Edrington advised.
Charlie Meyers: 303-954-1609 or cmeyers@denverpost.com
Bug update
Erratic low-level runoff has caused uncertain BWO activity on certain Colorado rivers but excellent hatches on others:
South Platte: “I saw bugs earlier than ever, well into mid-March,” reports Pat Dorsey, head guide at Blue Quill Angler in Evergreen (303-674-4700). “The best hatches have been below Deckers, closer to Trumbull.”
Eagle: “The BWOs are set to start any minute, now that the temperature has jumped back up,” said John Packer of Fly Fishing Outfitters in Avon (970-845-8090).
Colorado: “Our guides reported the emergers are really active in the Parshall area,” said Andrew Petersen of the Cutthroat Angler Shop in Silverthorne (970-262-2878). The flow is an agreeable 250 cfs.
Roaring Fork: Low-level melt-out caused muddy conditions from Carbondale down past the Colorado confluence. Locals are hoping for cooler weather to slow the runoff.
