Henry's Fork Fishing Report - October 23, 2025

Henry’s Fork Streamflows

Island Park Dam:  90 cfs (adjusted for the faulty gage reading on the USGS site)

Ashton Dam:  622 cfs

St. Anthony:  986 cfs

Fall River:  477 cfs

October on the Henry’s Fork has given us a decent month of fishing with some great days in the last two weeks.  This next week’s forecast shows some promise of continuity in this trend.  The river is low and weedy, water quality is very good, and the trout are hungry most days.  Cloudy to partly cloudy days will be stronger than sunny ones, but at this point in the deep fall, anglers will see hatches on most days, more sparse when the sun is shining.

Box Canyon

Late fall is a great time to fish the Box Canyon, our trout are putting on the final pounds before winter sets in and are feeding actively during periods of insect activity.  Wade anglers will find plenty of opportunity at these flows, provided they focus on water with deeper holding lies, a wading staff will come in handy for most.  Floaters should expect to walk the boat through shallow sections and plan on a float down the Box to take the better part of a day, it’s slow going in there at these flows.  Focus on deeper holding lies and fly selections should represent what is hatching out there at the moment:  baetis and midges.  Small flies will be more productive than large ones when nymphing.  Weeds remain an issue, so be sure to keep your flies clean!  In much of the canyon, the weight of tungsten beadheads will be sufficient to put your flies into play, but having a B shot or two handy for when you need them will come in handy.  Streamers can play as well, especially during periods of low light.

Railroad Ranch

This is a fun time to be on the Ranch, characterized by lots of rising trout, many small to mid-sized, with some larger ones mixed in there.  The size of trout can be tricky to discern from riseforms this time of year, many of the smaller trout are feeding rhythmically and effortlessly, with the cadence of larger trout.  Stay on the lookout for the telltale signs that bely the presence of a larger trout.  Noses, fins, weight of the rise ring, and the unmistakable sipping sound that only large trout make are some of these.  Mahoganies and Baetis are the primary food sources out there, bring along emerger, dun, and spinner imitations of them in a few varieties.  As ever, a patient and confident presentation will produce more consistently than a hasty and uncertain one.  Great dry fly fishing rarely lasts all day long this time of year, look to the midday hours from 10:00am-3:00pm for your best chances at success.

Canyon Country

While these sections are still beautiful and productive, their charm can diminish quickly when late fall weather moves in, these are long floats and generally not recommended at this time of year due to low flows and unpredictable temperatures.

Warm River to Ashton

This is a great piece of water that continues to deliver right to the end of the season.  Nymphing and streamers will be the most productive ways to fish here, but keeping a keen eye out for rising trout during periods of hatch activity can still provide opportunities at some fun trout on the surface.  Nymphs should be representative of stonefly nymphs, Baetis, Mahoganies and midges.  For streamers, classic colors like olive, black and white are consistent winners, but now is a great time to experiment with a variety of flies and sink tips in the many different water types found in this section.

Below Ashton Reservoir

The lower river is in play, and will be sensitive to weather, hatches will favor cloudy or partly cloudy conditions, but nymphs and streamers can produce on the sunnier days.  With the recent bump in flows in the Fall River, the Henry’s Fork remains fishable throughout these lower reaches, now is a fun time explore some of the lower river sections around St. Anthony and beyond.  Streamers are a fun way to search water, while nymphs will produce more trout in areas of higher concentrations.  Trout feeding on Baetis can be found throughout the system in certain areas. 

Get out there and have fun while we still can!