Henrys Fork Streamflows
Island Park Dam: 749 cfs
Ashton Dam: 2040 cfs
St. Anthony: 2990 cfs
Fall River: 1950 cfs
Fishing on the Henry’s Fork seems to be benefitting from this variable weather that keeps repeating, partly cloudy to cloudy days have been driving some good hatches throughout the system. Things are good out there and getting better this week! Flows are comfortable in the upper river and the lower river is still relatively high for the date which should keep things fishy for the next week.
The Box Canyon is on a steady wake up and seems to be getting more active as the days go by. At the current flows, structures are easily read and it is a joy to fish. There’s still enough water to keep the journey from getting too bumpy but there will be some rocks to avoid if you don’t want to leave bits of fiberglass behind! Indicator nymph rigs provide the best overall way to ply her waters, but at these flows dry/dropper rigs can be very effective as well. Golden Stones are always a possibility so be sure to have a few dry fly imitations on hand. Nymph selections should represent the abundance of caddis and PMDs out there, we are having the most luck with Zebra Midges in red and brown 14-16, PTs and Split Backs 14-16, Tactical R/L PTs in 12-14, Hare/Copper 14-16, and of course your favorite perdigons (Spanish Bullet, Olive Hot Spot, Jakes SH and Napoleon Jigs 14-18). I never head into the Box without some rubberlegs stonefly nymphs just in case as well.
As is typical for the Ranch opener, reports of success were widely varied, but most anglers are finding a few fish to engage. Be on the lookout for caddis 14-16 both tan and olive, PMDs 14-16, Flavs 12-14, and Green Drakes 10-12. This week might just see the arrival of Brown Drakes as well, so it would be good to be prepared for that should you get lucky and come across them. You’ll want to be equipped with emergent and spent/spinner versions of all of these bugs as well as having a few beetles and ants should you need a plan C on a picky fish. These days are beautiful on the Ranch, bring a water bottle and a rain jacket and take your flyrod for a walk in the Park!
With flows coming down out of Island Park Dam, the canyons are becoming more fishable, with structures more easily read and the fast water a bit easier to penetrate with the right flies. Stoneflies have past their peak but Golden Stones will be present throughout the summer in varying concentrations. We favor the “Chubberlegs” rig in here, a dry/dropper rig with a Chubby Chernobyl on top and a Rubberlegs nymph below. If fishing is slow, try dropping a large perdigon or BH Pheasant Tail 12-14 for more action. Streamers are, and will remain, a good option for those inclined to strip for a shot at one of the larger inhabitants. These canyons generally require a raft and some oarsmanship, make sure you are prepared if you venture into one of these two sections for a day’s adventure.
Warm River to Ashton
This week has seen the arrival of Green Drakes and Flavs down here, and has had some good dry fly fishing in addition to the standard nymphing approach. Weather looks to be fair for some continuance of these bugs, likely in spotty locations throughout the section, but it’s best to be prepared for dry fly action when the opportunity presents itself. Caddis are present in the system and fish are eating them as well. Outside of these opportune moments, anglers will do best to consider throwing an indicator nymphing rig or dry/dropper with a golden stone on top and the nymph of choice down below. The same selection for the Box Canyon will yield your best chances at success.
Below Ashton Dam
Flows remain hovering around 2000 cfs down here, which is relatively high for the date. These flows are great for keeping the river cool and fishy. We’ve been seeing a bit of a smorgasbord of bugs down here this last week and expect that to continue through this coming week. PMDs, Caddis, Green Drakes, Flavs, Olive Stones and Golden Stones are all present and anglers will want to keep a wide variety of flies available to imitate these bugs in their various stages of life and death. It’s a good idea to have a few gray drake spinners on hand as well, as we will likely see fishable populations of those by the end of this fishing report cycle. Dry fly fishing has been the standard down here, but there are a few people throwing nymphs and catching some fish as well. It’s peak dry fly season on the lower, so keep your eyes peeled for sneaky sipping fish as well as violent crashes out in the middle runs to give you a target. Remember that these fish don’t usually eat on the first good drift, persistence pays dividends, I like to cover a riseform with 10 good drifts before I think about changing the fly. There’s a lot happening under the water and these trout don’t eat every bug that goes overhead. Drag is the enemy and perfect drift is the goal.
Things have been crowded down here lately, and anglers are fishing with fervor, do your best to give other anglers some space and if you have a conflict, move along or find a kind way to approach it, a positive attitude goes a long way down here. Most of the land on the lower river is private property, anglers should be aware that fishing here is a privilege, not a right, respect the landowners and their rights.
Get out there and good luck!