Most interesting fishing on the lower river remains chasing browns during low light conditions. This means either “up & at ’em early” (like first light) or evenings. If this weekend storm materializes fishing could pick up during daytime hours. So could BWO activity. If you enjoy pitching streamers on a sink tip line, Box Canyon, with its almost impossibly low flow (currently 86 cfs meaning few if any boats), out of Island Park Dam is the place to go. So are The Tubs above Mack’s Inn where the wading is easier than in Box Canyon.
Almost anywhere along the river below the Warm River confluence will be a good location for encountering migrating brown trout. One location with excellent potential and plenty of room is along the river above the Wendell Bridge ( Highway 20). This puts one in position to intercept browns moving out of Ashton Reservoir which produced the current state record brown a few years ago. Early mornings and evenings will be best times, especially during these bright clear days. Oh, for some stormy weather!
Flow out of Island Park Dam was increased yesterday from around 200 cfs to nearly 300 cfs. Doesn’t sound like much, but at such a low flow it impacts best locations for wading. It is still a tough flow for drift boating, but remains good for wading. Big rubber legs and streamer patterns are the way to go this time of year. BWO activity is providing action almost everywhere on the river, upper and lower. Good streamer fishing on the lower river continues because browns are migrating. Locations to try are numerous in the river above Ashton Reservoir to Warm River. Others include from the Vernon Bridge upstream to Ashton Dam, below Chester Dam to St. Anthony, and in the river below St. Anthony (Sounds like the whole lower river!).
BWOs are bringing action from fish in the Last Chance-Harriman area and a few mahogany duns are around. Terrestrial insects and caddisflies are on the decline. Stonefly nymph patterns seem to work well in Box Canyon, especially during overcast and low light conditions. Browns are moving on the lower river meaning it is time to break out streamer patterns to be presented under low light conditions.Just above Ashton reservoir is a good place to try, but so are below Ashton Dam and Chester Dam. The uncertain weather predicted for the next several days also means good BWO activity, so don’t choose between their life cycle patterns and streamers. Take both!
This cool wet weather is making a difference with respect to fishing the lower river. BWO and midges are emerging in abundance, and mahogany duns are around. With terrestrial insects remaining top water fishing should be good for days to come, but as we move into October consider that presenting streamer patterns under low light conditions will become more important.
For Last Chance-Harriman its tricos in the morning, caddis and terrestrials during day time and that big hair mouse at twilight.This cool snap is just what is needed to improve fishing in the river below Ashton Dam. In the river above Ashton Reservoir its tricos in the AM, terrestrials (trailed by an ant pattern) during daytime, and streamers in the evening. Larger fish in the Flat Ranch preserve part of the river, aka Henry’s Lake Outlet, will move downstream to The Tubs area above Mack’s Inn. This translates to good streamer fishing in that part of the river.
There was a bear incident in Island Park recently, so it seems appropriate to mention not only bear spray but making noise to warn any bear that you are on the area and gives them a chance to get out of your way. It seems a lot less stressful if you let “brother (or sister) bruin” know you are in the area and it is time to leave, than is having to use that bear spray. Look at our current Yellowstone Park fishing report for some ideas on the subject of making noise to warn bears of your presence.
Flow out of Island Park Dam is considerably less than normal, so getting around to pitch those two nymph rigs or streamers in the evening is easier. Terrestrial patterns are the day time “name of the game” in the river below. Some tricos can make early AM fishing interesting. Are you more interested in fishing the lower river? The Warm River to Ashton part is the place to try. Terrestrial patterns (ant trailing a hopper) work well, and caddis and streamers in the evening will bring action. A good cold snap will improve action on the river below Ashton dam.
When honey ants show up on the river in the Harriman-Last Chance reach, fishing will really pick up. We cannot recommend the river below Ashton Dam as a great fishery until after Labor Day. The best fishing on the lower river now is between Warm River and Ashton. Try streamers, big nymph and rubber leg patterns under low light conditions. During day time hours slam (from a boat) or drop (while wading) hopper or hopper-like patterns beneath overhanging vegetation. Try the same with ant, adult cranefly and beetle patterns.
Looks like Henry’s Lake Outlet part of the river is now diminishing as a quality fishery for the year. That’s because flow out of Henry’s Lake has dropped meaning shallower and warming water. This will move fish downstream to the Henry’s Fork. For the near future you can find them in the Tubs area above Mack’s Inn. Try streamer patterns. For the rest of the river presenting terrestrial patterns is the best way to fishing success.