Submitted by TRR Outfitters on
It’s already September, and most of the summer heat should start to subside. That means the dog days of summer are behind us, with better fishing on the way!
Fall is one of our favorite seasons, as fish begin to feel the shorter days and cooler temperatures. That means it’s time to eat and get ready for winter! With the big bugs and summer mayfly hatches winding down, fall brings October caddis, craneflies, BWO’s, late-season caddis, and midges.
Hoppers will still play a role on most of our fisheries as we roll into October, so always keep a few in your box!
Owyhee River
If you missed the excellent PMD fishing this summer, don’t worry! BWO’s are starting to make a great showing and will be the dominant afternoon hatch as we roll into fall. They’re beginning to show around 2 p.m. and will continue into the later afternoon.
A typical day will bring midges in the morning through early afternoon, followed by BWO’s later in the day. Having an assortment of small Zebra Midge patterns in sizes #20–22, with variations of cream, red, and black, has been producing well. For BWO’s, having a selection of emergers, duns, and nymphs in sizes #18–22 will keep you covered.
Crowds tend to be busier from the morning into the afternoon, but late afternoon and evening have been much quieter and are still producing a good number of rising fish!
With flows hovering around 115 cfs and the reservoir level getting low, the water is very clear and still cold. Taking a different approach and using a little more stealth will still give you great days on this fishery. Sight-fishing for larger fish holding in the riffles during the afternoon has been great!
Just remember, these fish are seeing and eating a lot of bugs consistently, so presenting them with a small dessert plate—and doing it consistently—will get them to eat!
South Fork Boise Tailwater
Flows are on their way down on the South Fork of the Boise, and with that, much more of the river will open up for wade fishing. At 800 cfs, there’s still plenty of water for floating, but keep in mind that you’ll have more rocks to contend with. After Labor Day, flows will continue to drop. Generally, flows will go from 800 to 600 to 300 cfs throughout September and then remain around 300 cfs through the fall, winter, and spring.
For fall fishing, be prepared to see Pinks in September, but we’ll also expect to start seeing Blue-Winged Olives, October Caddis, craneflies, and Flavs. As the evenings get cooler, it’s not uncommon to see all of these bugs on the same day, so be prepared with something for each hatch in your box.
A good selection would include size 10 and 12 orange Elk Hair Caddis for the October Caddis, a variety of cranefly patterns, Thorax Dun Flavs in sizes 14 and 16, and Comparaduns in sizes 16, 18, and 20 for the BWOs. If any Pinks are still hanging around, have some Thorax or Parachute Pinks in sizes 14, 16, and 18.
If you don’t find anything rising, prospecting a dry-dropper with a Pat’s Rubberlegs or a small mayfly nymph has been productive.
Boise River In-Town
Like everywhere else in the area, flows will be dropping on the Boise River through town as we move into fall. As flows and water temperatures continue to fall, fishing will get better and better. As of early September, temperatures are still pretty warm in the afternoon on the lower stretches of the Boise. Until the evenings get cooler and water temperatures come down, focus your efforts earlier in the morning.
Nymphing is going to be the most productive. Small attractor nymphs generally work great on the Boise, so make sure to have Duracells, Blowtorches, Fire Starters, or just a good old-fashioned Pheasant Tail in sizes 14, 16, and 18. Pat’s Rubberlegs can also produce, even though the Boise doesn’t have a significant stonefly population.
All that said, the venerable Squirmy Worm might just be the number one fly to fish on the Boise, especially after a rain. While nymphing will by far produce the biggest numbers, fishing streamers can be a great way to find bigger, more aggressive fish. Try an orange crawfish pattern in sizes 4–6.
Call the shop at 208-939-6065 for consistent up to date fishing reports or to fine tune your skills and get out with one of our guides! We’re always here to help
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