For live and premium content, sign up for our email newsletter and we'll send reports directly to your inbox

Sign Up Now!

The Firehole River is a tough water to fish this time of year because escalating water temperatures make fish feed sporadically, and usually only late in the day. A trick I’ve learned is to concentrate your efforts downstream of cooler tributaries.

Some of these are only four feet wide; some are 10 to 15 feet wide. To locate them I simply walk the banks, though you can also get some leads by using a topographical map, available from shops in the Park or in West Yellowstone.

The water near the tributaries, I’ve found, not only holds more fish, but insects are more likely to hatch here. For instance, even in the mid summer heat of August, you can find mayflies hatching where Sentinel Creek enters the Firehole. To find Sentinel Creek, drive the Fountain Freight Road to Ojo Caliente Spring. Take the dirt road past the spring to the dead end parking area at the bend in the river. Directly across the river, you’ll see an island. Behind it is Sentinel Creek.

The mayflies begin hatching here in late afternoon. They can be imitated with size 16 or 18 Pale Evening Duns or Light Cahills tied with a pale olive body. This hatch is popular with locals, so don’t count on having the place to yourself every day.

If Sentinel Creek is taken, try Fairy Creek, a much smaller tributary, about 200 yards upstream on the same side. There are other small creeks flowing into the river, but the major tributaries are in the Bisquit Basin area. Iron Spring Creek and the Little Firehole enter near the bridge. Fish are also attracted to the small streams themselves, but it’s tough not to spook them when they are as concentrated as they are there.

Even anglers who know about these tributaries usually leave before the best of the fishing begins. It starts right before dark and right at the mouth of the tributaries. Big fish move up from the main river to dine on baitfish and smaller trout. With a streamer such as a Muddler Minnow, you have the chance to hook some very large fish.

It’s like bass fishing. Plop the streamer down at the mouth of the stream, watch a trout charge it, and try to wait for the hit. It’s exciting. It’s also nearly impossible to land the fish, since they invariably run up the tributary and are lost before you can wade out of the main river and give chase.

This kind of fishing is probably not what you came to the Firehole for, so let me tell you about one opportunity to do the difficult, fine fishing for which the Firehole is famous. It’s what I call the "white fly’ hatch. These insects are imitated by size 24 white midges. The trick here is to locate the hatch. The trout feed right next to the bank, and the rises are very delicate. Try wading the middle of the river in the flats above Nez Perce Creek and watching the banks for telltale rises. The insects themselves are almost impossible to see because of all the foam on the river.

The midge and mayfly hatches are best fished with a long, light rod. I like a nine foot rod, and since the work is delicate, I recommend a three or four weight line. For the streamers and hoppers, a six or seven weight rod is more appropriate. You’ll like the river, even in its summer laziness, but you’ll want to return in June or September when the Firehole is alive with rises. Scott Roederer.

Previous reading
Fly Fishing For Brown Trout
Next reading
Two “Ghost Town” Creeks Near The Beaverhead