Howdy y’all and welcome to the first fishing report of the 2023 season! We know some of you have called and emailed the shop regarding the status of these reports and are happy to be bringing them back as we anticipate another fine year of fishing on Henry’s Fork and other rivers here close to home. The biggest questions we have been getting lately have been the status of the salmon fly hatch on Henry’s Fork. Predicting the exact date for this hatch can be difficult especially when you account for the wide variation of temperatures found on the river due to controlled dam flows, tributaries that dump back into the main river systems, and a myriad of air temperatures through the day. This report will go into further detail about the status of the salmon fly hatch on each section of the river making any trip planning easier for the big bug chasers.
At the time of writing this report the flows out of Island Park Reservoir currently stand at 819 cfs, this flow is a little higher than what most would like to fish the box at and might make things a little difficult for the wading angler to get around, the best access for wading would be right at the boat ramp below the dam offering plenty of room for parking and walking around. The salmon flies have yet to hatch in numbers on the box, however you might find adults crawling and flying around where the Buffalo River dumps into the Henry’s Fork due to the warmer water found at the confluence and others stretched through the box. The adults should hatch in numbers here soon so be on the lookout. For this reason, throwing a dropper rig with a size 4 or 6 rubber legs underneath will be your best bet at finding fish still eating the crawling nymphs while also giving yourself an opportunity to potentially fool a couple on the dry. Mixing in other nymph patterns like big zebra midges, worms, and caddis’ can also help increase your chance of hooking up. The adults should start to hatch in good numbers the next couple days as water temperatures warm up.
As many of you might already know, the Harriman State Park section of Henry’s Fork is closed for fishing until June 15th, so not too much longer before we are casting to rising fish eating mayflies.
Mesa Falls to Ashton
The salmon flies on the Warm River to Ashton section can be seen crawling on banks and flying in decent numbers. Getting on the river in the afternoon will be important for anyone trying to chase this hatch as the day warms up. Fishing in this section has improved since the beginning of May as flows have steadily decreased to match snow melt. The name of the game while floating this section will be throwing more salmon fly dropper rigs with the big rubber leg underneath tight to banks as the hatch continues, do not be surprised if you find few fish eating the dry or nymph like you anticipate as the fish might be gorged on the big stonefly nymphs.
Lower Henry's Fork
Flows coming out of the Ashton Reservoir are currently at 2,070 cfs. I’ve heard of a good number of adults hanging around the banks and flying around as the hatch continues through the river. As echoed in the other sections, fishing a big salmon fly dry like a Henry’s Fork Foam Stone or Water Walker under a dropper tight to the banks will be your best bet at finding fish. Adding a green colored caddis nymph in your rig also might improve your luck with coming tight to fish. An adequate number of Caddis adults can be seen flying around, throwing a caddis dry fly can give the fish a different bug to look at potentially increasing your chances of finding fish. This section will be busy with other boats so anticipate heavy river traffic as people come up for the long weekend. For more information regarding specific patterns other than the ones mentioned in this report please stop by the shop and talk to our shop staff who will gladly point you in the right direction.
Flows out of the Madison are still high as runoff still passes through most rivers in Montana turning our favorite fisheries to chocolate milk slurries. Your best bet for finding fish on the Madison will be to nymph deep with rubber legs, worms, and egg patterns. Fishing the Madison right now might not be your best bet at finding copious amounts of fish but could produce nice fish-eating stonefly nymphs as we wait for the salmon flies to hatch on the Madison sometime in mid-July. Fishing on the Madison will only get better as runoff subsides and the salmon flies and caddis start to hatch.
South Fork of the Snake
Fishing on the South Fork right now is mainly a nymphing game as there are no major hatches currently happening to get these fish looking up. Fishing big heavy nymphs that will get down in front of the fish in deeper runs will give you the best luck at finding fish, bigger rubber legs and heavier tungsten beaded nymphs would be my choice of fly, fishing underneath an indicator. Fishing streamers would be another great option if you don’t fancy nymph fishing that much.
Fishing in the park has just opened over Memorial Day weakened and some mayflies can already be seen hatching in some of the waters. A hatch of PMDs can be found on the Firehole later in the afternoon as people pour from across the globe come to see the park’s beauty. Some of my favorite PMD patterns are a PMD tiltwing dun and cripple dun in a size 16 and 18. With the opening of the fishing season expect to be fishing in heavy crowds.