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“Shortbase”: and Diving Wasp Success
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Spring sets the stage for so many exciting outdoor changes and fishing opportunities. For some it can be baffling as where to go and what to fish for. Others pleasure and peace of mind may not be fishing at all. It is just as easy to get caught up in spring’s blossoming beauty and observing the wonders of nature in colorful habitats. A major spring highlight I eagerly look forward to each and every year is the exciting hatches of Hymenoptera (aquatic diving wasps). Triggered by the first warming trends or heat ups of spring. These big hunks of protein float up in mass numbers and inspire most every double digit fish to key in and carelessly pork. Those who are on top of it and fortunate enough to experience a feeding frenzy are generally never the same— totally jazzed, yearning for more and eagerly awaiting the next float up action.
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A Proven Selection. |
My first encounter with diving wasps was 20 years ago when the first heat up of the spring delivered a mass float up of exceptionally large (size 6-8) wasps on Lewiston Lake. At that time the second generation/start-up of Callibaetis had been going off and providing solid action. Periodically a loud slurp from a suspiciously large sized fish overshadowed the typical Callibaetis rises. I directed my Callibaetis patterns to the heavy rollers without success. Witnessing the large numbers of drifting duns and not receiving any takers was puzzling. Were these heavyweights keyed in on something else? Stunned at the sight, sounds and numbers of larger trout slurping got the best of me. No better way to possibly solve the equation than to lay down the rod and tune in. Close observations in the film revealed large black aquatics, closely resembling black flying ants. Ahhhh s_ _t out of luck— I had complete inventories of tired/true Callibaetis but no ants and as a result of no ant stash—no slabs. That night I called my good friend, Hal Jensen a popular and well recognized fly fishing legend and aquatic authority. I vividly remember the call. “Hey Hal, come on up. Every double digit trout in Lewie is gorging on large flying ants.” Hal patiently listened, paused, then started laughing before finally asking, “Herb, how many ants have you seen flying?” I gave it serious thought and mumbled “none.” That’s when he opened the door to my introduction and world of the Hymenoptera. But only before yanking my chain a half dozen times with knee slappers.
The order Hymenoptera is a large primarily terrestrial group of insects that include bees, wasps, ants etc. Their life cycle is much like a Steven King movie. The adult emergence (“float-ups”) is triggered by the first warm and windy weather patterns (80 degrees plus)…The adults maintain a low profile in the film, not easily recognized by the casual eye, and are often overshadowed by other aquatics before ultimately drifting ashore. They dry and fly straight to the trees such as oaks and evergreens to fornicate at night. Next day the females take flight and dives down to the bottom of the lake or river and deposits the eggs on the back of another aquatic to be used as a host, generally a caddis, damsel etc.. The wasp matures in a year and the cycle repeats itself. The larger (size 6-8) adults generally represent the first generation float-ups and most exciting. Surface takes on these large critters can be down right obnoxious. Smaller (size 10-12-14) most common generations follow. Depending upon weather/water conditions float ups occur right through May or until all generations have expired. They all activate a pork fest fly fisher’s dream about and one you most definitely want to participate.
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Flats + Diving Wasps=Full Net Slabs. |
Rich fertile ecosystems and clean cold waters generally support diving wasp. Some of the more popular waters I have experienced and successfully fished them are: Virtually most all Trinity waters (High mountain-Trinity-Lewiston Lakes) Trinity River, Lake Shasta, lower Sac, Hat Creek, and Lava Creek. Bass-trout-even squawfish all feast on’em…Each supporting population varieties and their own hatch time frames dictated by current weather/h20 conditions—spring is the season.
There are several fly patterns that are effective. (Trinity Fly Shop maintains a complete inventory of deadly “locally fashioned/tyed” wasp patterns). Size is most important. Match generation float ups. Secondly, pattern profile—keep’em greased and in the film. Although those who are really dialed, Like Hal, have experienced great success a day or two before major float ups fishing intermediate lines and wasp patterns in the mid-water columns. Last, color—generally black bodies with large brown wings. (Other varieties vary and reflect multi color bodies) Mix and match a complete inventory and don’t leave home without’em. Diving wasp float ups often happen when you least expect them. Don’t be on the loosing end. This spring be well prepared and in tune with conditions. Now turn off your TV & computer and go stretch a line!



