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A Blizzard In May: Caddis Fly Hatch About To Pop

FRISCO, Colo. (AP) - As the days get longer and the sun creeps higher into the sky, warm water migrates up the Arkansas River and little bugs start to hatch, surfacing out of the water in a mysterious way.

It's the caddis fly hatch, a time when the Arkansas River is frosted not with snow but with a multitude of white insects.

On a warm day in early to mid-May, one can sit by the river and watch. One or two beige-colored moth-looking creatures might pop to the surface, and before long, they're all over the place.

"It's amazing. They just start to appear," said Greg Felt of ArkAnglers in Salida. "It'll go from a few tens of them . and just exponentially expand."

In some years, the hatch is so prolific, it's called a "blizzard hatch," because it looks like it's snowing on a sunny day. Meanwhile, the river boils as fish break the surface to nab some protein after a long, cold winter and to build reserves for the high water season.

"It's like something out of the Discovery Channel," Felt said, adding that the magic number for water temperature is right around 54 degrees.

"To me, it's a moving blizzard that stages itself up river as the temperatures climb," said Jeff Schweitzer of Salida's Laughing Ladies Restaurant, a business that aims to draw the fishing business. "It's a sense of rebirth, in that so much life is coming out of the cold waters of the Arkansas."

The hatch isn't far away. Earlier this month, it was rolling upstream from Canon City, eventually fizzling out around Granite. The Buena Vista hatch generally occurs a week to 10 days after Salida, which Felt expects any day.

"It's normally happened by now, but we've had spells of cool weather that have held things up," he said. "There's a lot of pent-up bug energy."

The caddis fly looks like a small moth with a mottled wing. They flutter the way a moth does and they settle along the shoreline during their 10-day to two-week adult life span.

But the caddis flies on the Arkansas River aren't the only ones in Colorado. Jon Ewert with the Colorado Division of Wildlife said there are more than 200 species of the insects across the state, and several species along the Arkansas River itself.

"They have the most diversity in aquatic insects in the state," he said, adding that caddis flies are the most biologically advanced. In comparison, there are 90 species of stoneflies and about 100 species of mayflies, which are the "big three" in Colorado aquatic insects, he said.

The flies live as long as they do because they have basic digestive tracts that stoneflies and mayflies lack, allowing the caddis fly to sip nectar.

Caddis flies also spin silk, which creates the cone-shaped, quarter-inch casing they live in until they hatch. The casing has a small hole in the tail end that's used for respiration, Ewert said.

"Inside the case, they move their bodies such that water flows through the case and they get oxygen that way," he said.

He added a fun fact that some caddis flies elsewhere use their silk to make webs in the cobble at the bottom of the river to catch algae to eat.

When the flies get ready to hatch, they crawl out of their case toward shore, he said. That's when the fish are starting to "go nuts."

Almost immediately after the hatch, the insects begin to mate, beginning the reproduction process anew. Within a day or two, females lay eggs, dropping them to the bottom of the river where they stick to the rocks and begin to mature, remaining there until the same time next year.

Though the caddis flies that create the Arkansas River Valley spectacle of early May are short-lived, the species itself is a "summertime mainstay," Ewert said, with several hatches throughout the season.

Fly-fishermen are better off getting out on the front or tail end of the famed May hatch, because with so many bugs, the fisherman's imitation fly is but one of millions, and the fish are gorging themselves, said Zeke Hersh of Blue River Anglers in Frisco.

It's a fun time to fish, he said, because it's simpler to cast a single fly all day, dropping it on the water's surface and watching the fish breaking the surface to find food.

Though it can be tricky timing, it's "some of the most incredible dry fly fishing," Felt said, adding that what makes the Arkansas River Valley unique is that the air and water are getting warm but the snow's not yet melting, creating runoff that murks up the water.

"To be able to get out on a wild, free-flowing river and experience this kind of hatch and feeding frenzy . this is the river to do it on," Felt said.

"We have to get really hot before we start seeing runoff," he said, adding that enjoying warm days while fishing a clear river is ideal. "It takes a lot to really mess this river up."

"It's all about the fishing on the river right now," Schweitzer said.

Fishermen come from all over the state and region, many as repeat visitors who find Salida and Buena Vista a friendly place to fish. They often frequent his establishment in the winter-summer shoulder season (mostly because he offers steak specials throughout the month) to share tall tales and visit after some time away each other and the river.

"It's one of the few times there's a lot of fishermen here," Schweitzer said, adding that the influx for the hatch allows him to get reacquainted with the fishing community.

It's one bright light on the economic front at this time of year, Felt said, adding that the fishermen help with an "economic injection" before the summer season begins.

-By Janice Kurbjun, Summit Daily News

(Copyright 2011 by The Associated Press.  All Rights Reserved.)


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