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Fishing Report

Aug 9, 2012 | Mike Lawson

This has been a great week. A number of good things happened. My new book, Fly Fishing Guide to the Henry’s Fork has arrived. We just received word that the hardcover version will be here by this weekend. John McDaniel dropped a copy of his new book by our shop, Fly Fishing the Harriman Ranch, couple of days ago. It is packed with beautiful photographs, detailed information and John’s personal perspective of the primary place he has fished for trout since 1983. We anticipate the book will be available for sale within the next few days. Hopefully we can schedule a book signing day with John and me with our new books during the upcoming week. Most important is I had a chance to fish the Ranch a couple of times this week. All I can say is WOW! I’ve included detailed information on this in the Flat Water section of the report. I realize that a lot of this stuff should be listed in our Blog instead of the Fishing Report but, like a lot of guys my age; I don’t know the difference between a blog, a twitter, or a restaurant menu.

Upper Henry’s Fork

We’re into the hottest part of the summer. The air temperature in Island Park has been close to 90° F over the past week. Warm, dry weather requires more water for irrigation for the crops in the upper valley. The flow through the Box Canyon from the Island Park Dam is over 1500 cfs, about as high as it normally gets. Wading in the Box is difficult but the higher flows provide some great benefits. The water temperature remains cool at a time when some rivers in Yellowstone Park and Montana have been closed to fishing due to high water temperature. The high flows also move more trout into the banks. Streamer fishing has been good in the predawn and dusk hours. Use sculpins, zonkers and monstrosities like the Sex Dungeon and Circus Peanut developed by Kelly Galloup. Small Beadhead nymphs work best during the day. You’ll need to use a pair of tungsten beads to get the flies down. My favorites are Red or Olive Zebra Nymph, Flashback Pheasant Tail, and Skinny Nelson.

We’ve also had some good reports from anglers fishing the Henry’s Fork from Coffee Pot Rapids downstream to McCrea Bridge. The water in the Island Park Reservoir is dropping rapidly which will likely slow the fishing in this area.

Flat Water

One thing I love about August is that I don’t have to listen to all of the fishing bums that camp down by the gravel pits bitch about how crowded the river is and why everybody should go home but them. Thankfully, they all pack up and head to the next best place as soon as the drake obsession passes. In fact, I spent a couple of days on the Upper Missouri near Craig, Montana in the middle of July and they were all camped up there bitching about the same stuff. I love August!

August is my favorite time to fish the Ranch. It isn’t only because there is very light fishing pressure but the hatches are incredible, the trout have stacked on some weight since the early season, and they aren’t as wary from somebody throwing a Green Drake at them as soon as they stick their nose up.

Early in the week I was privileged to fish with my ole fishing buddy, Mick Mickelson. We rode our bikes in from the main parking lot. We left the bikes on the point at Coffee Pot Corner. Mick worked upstream to Lower Bonefish Flats while I ended up at the Whorehouse Pool below. There were nice fish rising everywhere. They were mostly feeding on Tricos but there were also two species of slow water caddis on the water. Callibaetis Spinners and Pale Morning Duns showed later in the morning. By noon the breeze kicked up and deposited hundreds on large Honey Ants on the surface. All in all it was a great morning. Unfortunately, I didn’t bring my “A” game and I donated flies to a number of big trout that broke my 6X tippet. I was glad when they switched to ants so I could cut back to 5X. I still lost a lot more fish than I landed.

I went back a couple of days later. This time I rode all the way to the high back overlooking Bonefish Flats. Everything was as it was before only this time I brought my “A” game. I hooked the first rainbow I cast to, an enormous female that jumped at least a half dozen times before I finally eased her to the bank. I can’t help but marvel at a fish like that, knowing that she is the survivor of thousands of eggs that were deposited in the gravel four or five years prior. I heard a commotion in the grass behind me as I was preparing to land my fish. It was a pair of young River Otters scampering over the grass. I kicked the water to chase them away because I didn’t need their help landing the fish. I worked my way upstream to the islands above Bonefish Flats. There was a pair of immature Bald Eagles sitting on a pole next to the water. Below them was another feeding trout.

After a few more casts I was hooked up again. This fish was a little smaller than the first but still would have gone over 20 inches. I picked off a couple more big fish on my Trico Spinner, amazed that I still had the original fly. I saw the first ants at 10:15 AM. A size 16 Honey Ant did the job on a couple more trout. As I worked down through Bonefish Flats the feeding intensity quieted. By noon when I got back to my bike it was a big empty river.

As I rode out I noticed a skiff pulled up next to the bank below the Middle Bridge. It was one of our guides, Tyler Treece. I walked down to his boat hoping to bum a bottle of water. His client, Greg Kirkman, had just landed a 25-1/2” rainbow on a hopper. Greg and his wife reported landed a number of large trout on hoppers.

The only problem with the Ranch is it is over by early afternoon. Drifting aquatic vegetation intensifies as the afternoon wears on, the insect activity drops off and the trout stop rising. If you’re on the water by 8:30 AM you should expect about 4 hours of good feeding activity. You can drive down below Osborne Bridge if you haven’t worn yourself out by early afternoon. There are a lot of springs that feed the river above Wood Road #16 and the PMDs emerge throughout the afternoon. These are the toughest, most selective, hard fighting trout on earth so if you get a couple of hookups, consider yourself lucky.

Riverside to Ashton Reservoir

The canyon water from Riverside Campground downstream to the confluence with Warm River essentially gets very little attention during mid-summer. The water is very similar to Box Canyon. Use the same patterns and techniques we recommend for Box Canyon. Now that the flows are high the fishing likely isn’t worth the effort unless your main objective is to get away from everybody. If you want to hike down into the canyon you likely won’t have any company.

The Warm River to Ashton float has been very productive. Most of the fish will be small but you will almost always hook up with a few trout in the 18” – 20” range in the course of the day. Whitefish are another treat that will keep the action going when fishing with nymphs. There are two good ways to catch trout on this float. Use a high visibility dry fly like a Chubby Chernobyl or Green Machine with a nymph dropper 24” below the dry. The most productive nymphs are Red, Olive and Green Zebra Nymphs, Tungsten P T Flashback, and Tungsten Prince Nymphs.

Ashton Tailwater

The river below Ashton and St Anthony always takes a hiatus during the middle part of the summer. Some anglers get pretty frustrated with this as there are lots of quality fish in this section. We feel it is beneficial in the long run. The water temperature ramps up, the river becomes choked with aquatic vegetation, the bugs quit coming off and the trout stop rising. In another week or so some of the backwaters will be productive with Tricos.

Madison River

As of this writing the water temperature at the Kirby Ranch is 20.1 Celsius (+68F) and 21.0 Celsius (+69.8F) at Cameron. When warm weather drives the water temperature up past 70F, as has happened during the past several summers, the trout feeding activity will drop dramatically. Your best option is to try to fish the Madison in the morning hours. Hopper fishing has been good. It’s not a bad idea to drop a black ant about a foot below the hopper, especially when the fish are getting worked over with hoppers. All in all, this has been one of the best seasons on the Madison in a long time. Hopefully the great fishing will continue.

South Fork of the Snake

Fishing the banks has been productive with hoppers, golden stones, and Chernobyl Ants. The riffle fishing has been relatively tough. PMDs and other mayflies don’t come off well in hot, dry weather. Things could change with some cloud cover.

Yellowstone Park

The water temperature is too warm on the Firehole, Madison, and Gibbon Rivers. These rivers will be closed to fishing until later in the season when the water cools back down. The trout numbers are thin on the Yellowstone River but the quality is high. There are some real big cutthroats that easily top 20 inches. Other good options in the park are the Lamar River, Slough Creek, and the upper reaches of the Gardiner River.


As always, Warm River and the Buffalo provide great fishing for small trout throughout the heat of the summer. Both streams are spring creeks that remain cool enough to keep trout active. Until recently Fall River has been quite high. The water level has dropped making the river much easier to access, wade and fish. If you haven’t fish Fall River you’ve missed a treat. It is one of the hidden gems in the Henry’s Fork region. Use tungsten bead nymphs dropped about 2 feet below an attractor dry fly. 


Warm weather has started to concentrate fish near the mouths of some of the springs and creeks. Targhee Creek has seen the most activity. Anglers have also been catching trout near Hope Creek near the cliffs, Staley Springs and in some of the deeper springs like the Blue Roof Hole out in the lake. Best patterns have been scuds, Mitey Mite, and Crystal Buggers.

Fly fishing at Island Park has been spotty but things are starting to pick up on the north side of the lake near Trude Bay and Grizzly Springs. Look for this fishing to improve as the reservoir level drops to meet downstream irrigation demand.

Gulper fishing has been productive on Hebgen Lake. Best action is during calm mornings when large trout cruise the surface feeding on Callibaetis mayflies. It is possible to catch trout from shore on the north side of the lake but in most cases you’ll need a float tube, pontoon boat or boat. Best action is to us a dry fly that is easy to see like a Parachute Adams with a size 16 Sawyer PT Nymph as a dropper about 8 inches below the fly.