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Tuesday, February 10, 2009

Stone Fly Nymphs Begin Molt

The Arkansas has been fishing pretty darned well on these nice days, and the fish are starting to move to the outside seams from the deep runs and pools. That behavior is a little early, but I believe that Stonefly nymphs have started to molt and that along with a little increase in water temperature has changed things dramatically. The best time to fish is from about 10AM till 3PM and the best rigs are deep running Stone Fly nymphs trailing a #16 BH Prince, Chartruese Copper John, or a #20 Red Pure Midge. A few fish are coming to the surface to eat adult midges, but very few.

On rivers like the Arkansas, Stonefly nymphs offer up their protein load to fish coming out of the winter doldrums. There are obviously a lot of different stonefly species in our rivers, but the one that really kicks off the feeding frenzy are the Golden Stones, Hesperoperla pacifica and Claassenia sabulosa . These are fairly large bugs measuring from 24 to 38 mm or on the average a little over an inch long. When they are mature, they have a dark brown back with a yellow underbody. These insects live in the nymphal stage for two years during which time they undergoe several instar phases or molts. Like a snake, everytime the insect sheds is exoskeleton, it grows a little. It's hard to say exactly how many instars it goes through, but most folks think somewhere between 7 and 12. I personally don't really care. All I know is that sometime in mid to late February (this year the first of February) through early April, the little beggars molt and drive the fish crazy. The molt occurs around daybreak and anywhere from 6 to 8 hours later, the nymphs have hardened up again and turn darker. So, in the mornings, they have a buttery translucent appearance to the fish, making them a wonderful food source. I think they probably look a lot like Mom's mac and cheese or a wonderful dish of veal picatta. Perhaps not.... Anyway, you want to fish the golden stone imitations in the mornings until mid afternoon, then switch back to the darker ones. Remember, not every stonefly nymph in the river is exactly the same age, so this process continues for a few weeks. A golden stone nymph is always my lead nymph through the spring hatches. On cloudy days, I trail it with Larry's #20 Black Ice for a Baetis nymph and in early April I always tie in on with a Caddis Larva. In late February and early March I will fish it by itself with about three split shot on a 6 foot leader. I use the short line, bounce nymph method in heavy, choppy water. That's where the creatures live, so that where you need to be. Keep adding split shot until you get the nymph on the bottom quickly. Don't work into position just to have your bug float over the heads of the fish. Forget the strike indicator and high stick the fly through the rocky bottom. Takes will be unmistakable, so don't worry too much about that. Just keep the thing bouncing along through the drift.