Fall River Basin streams are quite low for this time of year, but water temperatures are ideal. Other than tricos, you will not find the large and varied mayfly emergences here the Henry’s Fork or the Madison River offer this time of year. A few BWOs and even fewer mahogany duns emerge, but terrestrial insect populations will remain strong until the first killing frost. So go with dry ant, beetle, cricket, horsefly, and hopper patterns. Try trailing that big hopper pattern with an ant, beetle, or horsefly pattern. Because water is low and sunlight is diminishing, daytime dry fly fishing can be good after water warms to around fifty degrees F. To be successful, however, you will need all the stealth you have learned from fishing the Harriman reach of the Henry’s Fork and then some because of the smaller water. But the rewards can be fish ranging to the same large sizes. Elsewhere, the Firehole River is entering its famed fall season as BWOs emerge while the region cools and days shorten. Run-up browns and ‘bows from Hebgen Reservoir are coming into the Madison River above and the same will begin soon as Shoshone and Lewis Lake browns will stack up in the river between. Fall season mayflies are making for good fishing on streams (Lamar River, Slough and Soda Butte Creeks) in the northeast part of the Park. Crowds are down, insect pests are dying off, and cooler weather prevails. It’s a great time to enjoy fishing Park waters.