September continues to offer spectacular weather and excellent fishing. Currently, the Big Wood River is fishing very well as Tricos and Baetis make their concurrent appearance. Red Quills are also entering the picture as the sun warms the river system in the afternoons. Silver Creek is fishing nicely as the Callibaetis make their midday presence in significant numbers and the approach of the Mahogany Dun nears. The Big Lost River is on fire with an abundance of Tricos bouncing in the mornings and larger terrestrials present in the afternoons. The South Fork of the Boise is now flowing at 300cfs which lends itself to productive walk and wade angling. The Salmon River continues to fish exceedingly well with terrestrial/dropper rigs and double nymph setups. If fishing is your top autumn priority, now is the time to take advantage of the fine fishing before winter moves in and slows the productivity significantly.
Big Wood River
The Wood, like the other river systems in the Valley, is fishing well especially once the fall sunshine warms the air and water in the middle of the day. No need to wake early this time of year – the fish remain lethargic until the system warms, but when it does, trout are taking imitations with reckless abandon. Tricos are a challenging and exciting insect to imitate and when presented with little or no drag to surfacing fish, these bugs can lead to fantastic fishing. The small Baetis is also present on the Wood, as it has been for some time, and can be an excellent alternative for picky fish. The Red Quill, also known as the Hecuba, will be seen from midday into the late afternoon depending on daily weather and river section selection. This Green Drake-like mayfly is a real treat to throw and is hard to miss as it flutters above the water surface. All patterns from cripple emergers to duns can be effective and even the largest of rainbows will come to the surface for these tasty treats. Hoppers and October Caddis are also good selections for top water action which gives great relief to those tired of fishing Tricos.
The Creek, on a warm September day, is as stunningly beautiful a fishing destination as any in the Continental U.S. The Callibaetis are thick from noontime into the afternoon offering top notch angling action whether with a dun or spinner pattern. The concurrent spinner fall/emergence leads to some aggressive takes by feisty ‘bows and browns as does nymphing. It is possible now to begin to see the Mahogany Dun in the afternoons on the Creek which are slightly larger than the Callibaetis (perhaps as large as #14s). This September visitor is as beautiful as any mayfly, offering a burgundy thorax buffeted by slate wings. Hoppers and other terrestrials are still very much worth casting when the mayfly action dwindles, especially on breezy days.
Big Lost River
The Lost (336cfs) may be the pick of the litter at the moment as the Trico action in the mornings is spectacular. Trout are rising to spinners and duns in the morning hours especially in the slicker pools and deeper holes. Soon the larger Blue Winged Olive will appear as well, but for now look to the little black and white mayflies as your prime morning choice. The afternoons will feature excellent nymphing opportunities. Try using a mayfly nymph (size 12-14) accompanied by a small Zebra Midge (size 20) and you should see first-class results. Terrestrials are still an afternoon option here as they are on most of our river systems, although their summer run is nearing its annual end.
Upper Big Lost / Copper Basin
The alpine streams which have produced so well this summer are beginning to revert toward their winter norms. Unfortunately, that means it is time to start looking downstream toward larger water, higher food source volume and slightly warmer water temperatures. One can still draw strikes with large attractor patterns and standard nymphing techniques, but because of the cold night time temperatures, one should plan the day around afternoon fishing. These beautiful headwater streams are no longer producing as they did through the summer months, but what a summer it was!
South Fork of the Boise
The South Fork of the Boise is now flowing at 300cfs. Drift boats are no longer necessary on this tail water, but the walk and wade fishing can be superb. Sight-fishing with Caddis, Parachute Adams and terrestrials is an excellent approach as many of the larger fish which have been hiding all summer are now visible and accessible. Stories of gargantuan rainbows and bull trout abound on this river and there may be no better time to stalk them than now.
One of the most overlooked stretches of river in our region in the Salmon River. Home to anadromous fish such as Steelhead and Chinook salmon, the Salmon is also home to Rainbows, Cutthroats, Cuttbows, Whitefish, Bull Trout, Brook Trout and Squawfish. It is not uncommon to catch multiple species in the same day, even in the same hole! Although fishing around Stanley can be fun, try the lower reaches of the river between Sunbeam Dam and Challis. Double nymph rigs, hopper/droppers and leach patterns can lead to a spectacular day’s angling on one of the most majestic freestones in the West.