Henry's Fork Report

Henry’s Fork Streamflows

Island Park Dam:  155 cfs

Ashton Dam:  779 cfs

St. Anthony:  676 cfs

Fall River:  382 cfs

October is the new September in Henry’s Fork country this week, with beautiful weather and warm temperatures forecasted through the week.  Flows are low throughout the river and this fall is proving to be more reflective of a late summer than the cold autumn that we are used to.  Look for fishing windows to be longer than they would be otherwise, but sunny weather won’t do much for dry fly fishing, so be prepared to fish subsurface for at least part of the day or go on the hunt for a rising fish during periods of insect activity.  Terrestrials aren’t totally out of the question, there are still some hoppers around out there.

Box Canyon

At these flows, anglers should fasten their seat belts or make sure they’re stable in the leg locks as hitting some rocks is an unavoidable fact.  Walking boats through the shallow reaches is a necessity in some areas and floaters should be prepared to push boats up and over a few flat rocks along the way.  That said, fishing in these conditions can be excellent with temperatures in the optimal range for trout activity and flows concentrating fish into more obvious holding water.  This is a great time of year to wade fish the Box Canyon, a wading staff is recommended for anyone who isn’t an expert wader.  Shallow indicator rigs are the norm and the most productive rig, but at these flows dry/dropper rigs can be used to effectively cover much of the holding water as well.  Fly selection should represent midges, baetis, mahoganies, stoneflies, and small caddis.  We keep our Box Canyon flyboxes filled with:  red, black and brown zebra midges #16-20;  PTs, Micro Mays, Shop Vacs and Juju Baetis #16-20; HP Caddis Pupa and Hare/Copper #16-18;  Rubberlegs Stonefly nymphs #8-10.  For perdigon style flies we like the following:  Olive Hot Spot, Spanish Bullet, Bullet Quill, Jakes SH, red Jig Napoleons, Frenchies and Black Daggers #16-20.

Railroad Ranch

What is usually a wonderful time on the Ranch has been a quest for quality trout amidst plenty of smaller rising trout.  There are some good trout feeding out there, but anglers should be prepared to carefully study riseforms to distinguish large trout from smaller ones.  Cloudy and rainy weather will help to bring larger fish to the surface, and they’ll be more challenging to locate on sunny days with more sparse feeding.  On these warm afternoons, a hopper is still worth trying, there are still some around when it feels like late summer out there.  Keep a close eye out for Mahogany Duns, if you find them in good number, you’ll usually find a few nice trout feeding on them in the emerger or dun stages.  Daily hatches of pseudos and some small baetis are the current pattern, a sprinkling of mahoganies in there as well.  A little cloud cover will bring out more mahoganies and keep them around longer.  Be sure to bring a good variety of small spinners, baetis emergers and duns, as well as mahogany emergers and duns to give yourself a fighting chance should you find a few quality trout to pursue.  Keep a hopper or two in your hat to cover a trout you’ve seen rise only once or twice that refuses to do it regularly.

Canyon Country

Usually, the weather keeps us out of these canyon sections at this time of year, but a decent forecast of fair weather will draw us back into these opportunistic reaches of the Henry’s Fork.  These are beautiful and remote sections that are best enjoyed in nice weather, but be sure to bring extra layers and a rain jacket regardless of what the forecast says, things turn cold quickly in here this time of year.  Dry/droppers are the norm, but a short leash indicator nymphing rig is an excellent choice as well.  Streamers will play in the fast water, bright or flashy flies are worth trying on a sunny day, dark colors once the light comes off the water.

Warm River to Ashton

This section is a fair bet on just about any day of the week and in just about any weather for good action on small to medium sized trout.  There are a few surprises in there this time of year and anglers can always choose to pursue brown trout on the move.  Indicator rigs are the normal choice but dry/droppers and streamers can be used on most days with success as well.  This is a great time of year to bring along a sink tip to work a streamer in some of the larger pools.  A warm afternoon can yield decent “hoppertunity” in the lower reaches as well.

Below Ashton Reservoir

We all wish for some cloudy weather to bring out the best in these lower river sections during the fall, but when fair weather prevails we know that the action will be better with nymphs under a dry fly or indicator.  Dry fly activity will be short and sweet on fair days, with larger trout showing themselves less frequently and less obviously.  Keep an eye out for sneaky sippers dining on baetis or the occasional mahogany dun.  Streamers are worth a shot down here, light flies on a floating line are usually best.

Hope for clouds but enjoy the sunny days, have fun out there!