For at least half of the year, my attention is leveled on the Caldera section of the Henry’s Fork in Island Park where gentle currents and mostly wadeable water are the primary characteristics of the fishery. By late fall, however, I become reunited with a different stretch of the river that flows near our winter home in St. Anthony, about 30 miles downstream.

Wider, deeper, and faster, the lower Henry’s Fork is best accessed by drift boat from May through early September, and sometimes even longer. But changes occur by October when peak demands for irrigation and hydroelectric generation have passed and the demeanor of the river becomes more accommodating to the wading angler. With the exception of areas at Chester Dam and Fun Farm, the 15 miles of water downstream from Ashton Dam to St. Anthony becomes reasonably safe and comfortable for wading when flows from Island Park Reservoir and numerous tributaries are at a yearly low. Additionally, an elevation that is more than 1,000 feet lower than Island Park reduces weather extremes that can impact comfort and access during the shorter days of the off season.

With trout concentrated into the deeper runs and pools, the low flows of autumn and early winter create an enhanced access to a mixed population of rainbows and browns. Baetis and midge hatches during the warmer parts of the day can produce dry fly action rivaling any other season in terms of the number of rising trout that become available. But the demands are high when the natural insects start at size 20 and range downward from there. Subsurface nymphing with small, weighted patterns is probably the most productive fishing method over a larger portion of the day or beyond the time when air and water temperatures drop below the freezing point. Nymphing is also likely to yield a better average in terms of the individual size of the catch. 
Generally speaking, I prefer dry fly fishing when a choice exists, but refined nymphing in clear, shallow water would not be ranked much lower. However, there is a time in the late season when a reunion with the burly browns of the lower Fork takes control of my attention. From late October through most of November, I am likely to be found in the canyon stretches throwing big streamers on a 6 or 7 weight rod. Exercising this heavier gear combined with the realities of being an older man can seem more like work than pleasure at the end of a day when several miles of wading and countless casts have taken their toll on an aging body.
With memories spanning decades, it is the mind state rather than the potential for spectacular results that drives the desire to renew a relationship with water I cannot reach at any other time of year and the descendants of great trout that will probably never be exceeded in size or personal significance. Adorned in the flaming colors of autumn and bearing the defiant attitude of a rutting bull elk, a big male brown is a different animal when compared to the reclusive creature he becomes at any other time of year. 
Emboldened by the prospect of female attention, a big buck fish seems always ready for combat with competition of any size and, in my opinion it would be next to impossible to fish a streamer that is too large.  Because he strikes in anger not the feeding urge, I fish a big streamer in a manner intended to provoke an aggressive reaction toward an unwelcome intruder. Swimming the fly at a slower speed that depicts an adversary that is not retreating can be a better choice than trying to imitate a fleeing rival by quick stripping the fly.
With a strong hook jaw and menacing teeth, a lovesick brown can dispatch with ease a smaller whitefish or trout that is just simply in the wrong place at the wrong time. A trout in this mode of ferocity will attack a streamer with more force than I have ever witnessed in fresh water. A heavy tippet and strong hook are essential for fish that, in some instances, can pressure a 7 wt rod to its limit. 

There are many ways to pursue trout with a fly rod, and I enjoy them all. But at the end of a season and with winter lying directly ahead, I appreciate the lower Henry’s Fork more than at any other time. With frigid conditions through much of December, January, and February, each day on the water prior to that period is savored. Hunting big browns in the final days of fall is a fitting conclusion to each year, and I am grateful that the tradition continues.  

words by René Harrop
photos bt Bryan Gregson