Thundershowers are predicted for this weekend. If they happen, look for fishing on most streams to pick up. Only “fly in the ointment” would be a shower with a direct hit on stream side formations with a tendency to erode and slough into the stream. This happens on the Lamar and Snake rivers frequently during big showers. Go with tricos for early morning action, and switch to terrestrial patterns around mid day for most streams.
We found that fish in the Grey’s River were quite cautious until a few PMDs came out late last Thursday afternoon. They loosened up a bit then, and we landed a few gorgeous Snake River Fine Spotted cutts. If you have never visited this classic freestone stream, consider doing so. It is just a few miles east of Alpine, Wyoming. The countryside, even with the prevailing haze, is as beautiful as it comes. Above the Murphy Creek Bridge fishing is legal with flies and lures only. You can buy a license ($14 for a non-resident single day) in Alpine, and stop for a “stick-to-your-ribs” breakfast. Take a good camera, terrestrial and PMD life cycle patterns.
Mackay Reservoir offers the best still water fishing in the area. Fish the river and creek channels coming into the upper end. Midge pupa patterns and damselfly nymph patterns, both under an indicator are good ways to meet action from big rainbows and kokanee. This is a high country reservoir where air is cooling down, so barring big draw-down water should remain cool for good fishing barring a big draw-down.
Best news here is that PacifiCorp, the owner of Ashton Dam has decided not to lower Ashton Reservoir to stop seepage under the coffer dam. See details on the Henry’s Fork Foundation web site on how they plan to stop the seepage. The solution PacifiCorp proposes keeps the best interests of the Henry’s Fork fishery up front, something we all want to happen. Meanwhile go to the upper river around Harriman, Last Chance, and Coffee Pot for best fishing. Go early in the day for the trico activity, switch to terrestrial patterns when they fade out. Switch to caddis in the evening, and don’t forget that hair mouse! If you fish The Tubs area above Mack’s Inn, go very late or very early in the day to avoid the recreational floaters. Try streamers in the deep runs that give The Tubs their names.
So far this season the gulpers on Hebgen Lake have been rather spotty in their activity. No one knows for sure why, but there are a lot of discussions out there on the subject. The peak of activity is usually right about now. Some good advise seems that moving around from location to location as the days go by can bring more success.
Now is a great time to try small streams for action and a good measure of solitude. Off the beaten path, the Salt River tributaries coming out of Idaho are worthy of a visit. Jackknife, Tincup, Stump, Tyhee, and Crow creeks are mainly cutthroat fisheries, but all have more or less brown trout. South Fork of Tincup Creek is all cutts. Early in the day tricos can be seen on each, and by mid day terrestrial patterns bring action, later caddis swarms bring action. Traditional attractor patterns in smaller sizes always work. Lightweight rods (2 to 4 weight) are ideal for each. For sure most of the fish run small, but some large specimens are present and can really fool you.
Early in the day trico hatches (females) and spinner fall (males) is making for good fishing. Wading conditions in the river below the dam are good, too. Switch to terrestrial patterns as the tricos ease off later in the morning.
Trico emergences are making for good early in the day fishing on the Madison River and on Fall River Basin streams. It all ends before noon. After that, switch to terrestrial patterns and hope for a cumulus build-up. The Gallatin River along Highway 191 is fishing very well if you can find a spot in a pull-out. Early AM trico activity is good. Afterwards a switch to terrestrial and traditional attractor patterns works. Later in the day, switch over to dry caddis patterns. The same will work on nearby Grayling Creek, and fewer folks will be fishing there.