Claassenia and Hecuba are out. It feels like Autumn

Snake River

Claassenia stoneflies continue their emergence on most reaches and grasshopper continue to make racket on the banks. PMDs are still around but waning except for those days with clouds and precipitation. We are also beginning to see our first Hecubas of the year, and we are also seeing more of them on those days with cloud cover (and a bit more intensity on those afternoons with precipitation).

On the lower river from South Park down to Sheep Gulch, banks, structure, and eddies are outperforming all other holding waters with larger attractor and grasshopper imitations. Riffles, seams and confluences are active later in the day from around 1pm to 4pm or 5pm with smaller mayfly patterns. The upper and mid-reaches from the Dam down to South Park have decent action in the morning hours with surface flies but turn on in a bigger fashion from around 11am until 2pm before action slows a bit. Hecuba imitations hit their stride after 1pm in riffles, confluences, and banks and bankside troughs with moderate currents and depths.

Nymphs have been performing well on all reaches and in most water types. Going a bit deeper than usual for this time of year is the trick. Dry-dropper rigs are working best with three to four feet of dropper tippet. Double/triple nymph rigs are producing best with six to seven feet of leader from trailing fly to line/suspension device. at the same time, parts of the day, particularly mid-day from 10am until 3pm, better action is coming by going one foot shorter with your dropper tippet and two feet shorter with double/triple nymph rigs.

Streamers are working in intermittent fashion throughout the drainage. Some days mornings are the key time while other days its more early afternoon from around 11:30 to 2pm. No rhyme or reason to the sink rates you are using. At times there will be plenty of production on floating lines or INT tips. Other times will require something akin to a 3ips to 6ips tips. No matter what you do, target fast water confluences, fast water troughs, banks, structure, and seams separating main channel currents from backwaters and vary up your retrieval tempo and hesitations of line strips.

Dry flies – Circus Peanuts, Mary Kays, Bart’s Lipstick, Purple Bruces, Will’s Winged Chernobyl, Parachute Hoppers, Juan’s Lil’ Hopper, Flesh Hoppers, Parachute Hares Ears, Booty’s Drake Emerger, Parachute Extended Body PMDs, mahogany duns and gray drakes, Copper Hazes, Parachute Adams, Comparaduns, Booty’s DL Cripple, Quigley Cripples, and Film Critics.

Nymphs – 20-Inchers, Peach Fuzz Jigs, Brillion’s Lucent Jig in pink or orange, Hares Ear Nymph, Copper Johns in red or copper, Hala Girls in pink, Lightening Bugs, and Psycho Princes.

Streamers – Booty’s Quad Bunny, Galloup’s Boogeyman, Keller’s Nightmare, McKnight’s Home Invader, Goldies, Mojo Minnows, Booty Call Minnows, Arum’s Lil’ Kim, and Kreelux.

South Fork

Caddis are present in the early morning hours from around dawn until 10am on the upper reaches of the South Fork. Mutant stones are present everywhere but most evident on the lower reaches from Wolverine down to Lorenzo. And while PMDs are waning some, the will still be the most prolific emergence just about every day (we are seeing a fair amount of them on the few cooler and wetter days we have had. Expect that to happen with a bit more frequency as we move into September). All of this is leading to decent surface action. Most imitations will work in most water types at some point during the day. This includes larger attractor/hopper imitations in riffles and deep seams. Nevertheless, warm air and water temps are leading to a noticeable slowdown on every reach after 2pm (except on those days with afternoon showers).

Nymphing has been quite consistent throughout most of the day on all reaches. Banks, structure, bankside troughs and seams are fishing best in the morning, while riffles, riffles pools, side channels, and eddies can produce throughout the day. As with surface patterns, there is a noticeable slowdown after 2pm. Double/triple nymph rigs are working best with six to seven feet of leader from trailing fly to line/suspension device. Dry-dropper rigs are best fished with three to five feet of tippet. Keep an eye out for suspended vegetation, which is starting to increase as the season progresses.

Streamers have been hit-or-miss as it has been for a good part of the past month but can be worth it when it is on. The lower reaches - Cottonwood to Lorenzo – has been more consistent. Morning hours from dawn until around 1pm is the sweet spot but can still be spotty from time to time. Go with sinking tips in the 3ips to 8ips range or six foot lengths of T-8 or T-11 and target banks, structure, backwaters near main current seams, riffle current margins, and the inside turn of riffles. Moderately sized patterns are working better than larger baitfish imitations. Doubling up moderately sized patterns can outperform single streamers some days.

Dry flies – Snake River Water Walkers, Circus Peanuts, Chubby Chernobyls, Parachute Hoppers, Morrish Hoppers, Elk Hair Caddis, Sparkle Caddis, Peking Caddis, Goddard Caddis, Parachute Extended Body PMDs and Mahogany Duns, Parachute Adams, Comparaduns, Snowshoe Duns, Booty’s DL Cripple, Booty’s PMD Emerger, Q’s Loop Wing Cripple, and Film Critics.

Nymphs – Pat’s Rubber Leg, Keller’s Peach Fuzz Jigs, Brillion’s Lucent Jigs, Duracells, Prince Nymphs, Booty’s Deep Stinker Nymph, Copper Johns in red, Bruised Mays, Panty Droppers, Psycho Princes, Lightening Bugs, Rainbow Warriors, and Perdigons.

Streamers – Sundell’s Ghost Dancer, Kill Whitey, Trevor’s Sculpin, Jointed Urchins, Coffey’s Sparkle Minnow, Strolis’ Masked Avenger, McKnight’s Home Invader, Baby Gongas, Doc’s Smelt, and Lil’ Kims.

Flat Creek

Production on terrestrial imitations and foam attractor patterns (#12 to #14) is occurring squarely in the morning hours from roughly dawn until just before 8am, although don’t expect it every single day. These patterns are not offering much after 9am except for sprodic takes every now and then. More consistent action is happening with PMD and mahogany dun imitations. The latter is hatching with far more frequency but should intensify as we get deeper into September. Emergent and dun patterns are working best along undercut banks and troughs mid-day and in riffles and seams in the evening.

Nymphs imitating caddis and mayflies are producing throughout the day but are working best from around 1pm until dusk with 2pm to 6pm being the sweet spot. Fish your nymphs as dropper with around 10 to 18 inches of tippet depending on sink rate or using wool indicators or fly line with two to three feet of leader from trailing fly to your mode of suspension and target undercut banks, structure, troughs, riffles, seams, and eddies.

Dry flies – Micro Peanuts, Will’s Micro Chernobyl, Parachute Hoppers, Juan’s Lil’ Hopper, Bear’s No Hackle Ant, Galloup’s Ant Acid, Parachute Extended Body PMDs and Mahogany Duns, Thorax PMDs, Harrop’s PMD, Chez’s Hi-Viz PMD, Snowshoe PMDs, Comparaduns, Rusty Spinners, Booty’s DL Cripple, and Film Critics.

Nymphs – Lite Brite Serendipities, Soft Hackles, LOF Pheasant Tails, Copper Johns in red, olive, or black, Psycho Princes, Panty Droppers, Lightening Bugs, Rainbow Warriors, and Perdigons.