No year-end summary would ever be complete without describing how water, in its various forms, affected the fishing during a season that has just ended. On the Henry’s Fork it begins with the snow pack which combines with water carried over in the Island Park Reservoir to determine winter flows. These levels dictate the survival of young trout while influencing the overall health of the river. For more than a decade it has seldom been possible to report more than adequate winter flows, but that has changed in recent years. 

2011 marked the third consecutive year of reasonably good carryover in the reservoir and a snow pack roughly equal to the historic average. With flows of 300 cfs through the harvest portion of the year, the continued momentum of a rebounding fishery seemed a certainty. In the local community optimism ran high as hatches of Baetis and Midges began to appear in March and early April. But as May approached snow continued to accumulate in the high country, and the weather stayed cold even on the lower river near St. Anthony. Precipitation in the form of snow is not uncommon at this time of the season, but last year it became the rule. Mother’s Day caddis and March Brown mayflies are seldom hampered by a spring rain which can often stimulate the action, but sustained freezing temperatures and snow fall are a different story. With dry fly fishing largely curtailed and our annual move back to Last Chance delayed until nearly Memorial Day, all bets were off with regard to the Salmon Fly hatch. But even early June would not see a significant change in a weather pattern that continued to build the snow pack to a near record level.

As in the past when spring runoff exceeds the capacity of Island Park Reservoir, the upper Henry’s Fork ran higher than what some have come to expect through much of the month of June but the hatches and resulting fishing were not largely disappointing. The lower river, however, was a different story. With no reservoir storage to capture or at least delay a rapid snow melt from tributaries below Mesa Falls, the river downstream swelled to levels seldom if ever witnessed by the old guy who pens this report. However, the torrential rage that continued to plague some neighboring rivers well into the summer was mercifully confined to about ten days on the Henry’s Fork.

While disruptive throughout much of the early season, there was an upside to the higher than usual flows on the lower river. Gray Drakes which are all but absent in years of low flow came into full bloom as the end of June drew near, and anglers prospered despite some rather risky wading conditions. With caddis, Green Drakes, Flavs and Golden Stones added to the mix, fishermen were treated to an additional two weeks of excellent fishing on water that often becomes rather quiet in early July.

With favorable flows that kept the trout well dispersed from Box Canyon through Pinehaven, the upper river began a timely distribution of hatches that equaled or perhaps even exceeded those of the previous year. The show began with caddis and PMDs at about the time as the opening of the Ranch, and a larger than usual appearance of Black Winged Ants in size 14 followed closely thereafter. As might be expected given the extreme of earlier conditions, Green and Brown Drakes were a little late in arriving, but there was no shortage of excitement once they appeared. Also somewhat tardy were the Flavs which typically show up by late June. There were no complaints in early August, however, when a Flav Spinner fall could still be savored until sunset.

To describe last summer as a somewhat abbreviated affair would probably be an understatement, or at least that is how it appeared early on. But as the days became more reflective of the season in mid-July, morning hatches of Callibaetis and Tricos teamed with the PMDs to provide consistent opportunity well beyond the period that could normally be expected. And at a time when my thoughts might otherwise drift toward Hebgen Lake or the Madison, there was no way I could leave Idaho and what lie directly ahead.

With temperatures in the mid-eighties as a near constant daily feature, August delivered a virtual cornucopia of insect life both aquatic and terrestrial. Early risers were often greeted by a Trico emergence at 7:00 A.M. quickly followed by an assortment of mayfly spinners and caddis that could keep the trout looking up through mid-morning. And there were days when a lunch break became a forgotten notion as the activity transitioned seamlessly into a PMD hatch that might last into early evening.

From late morning through early afternoon there was always the possibility that the big Honey Ants would make a showing, and trout response to this event was inevitably spectacular. More consistent were the smaller black variety which brought equal if less dramatic response than their larger cousins, even though some would be stretched to make a size 22. Red Ants in size 16 and Cinnamon in size 18 were also part of a mix that individually or collectively could drive the big rainbows crazy.

Unlike 2010 which was a banner year, hoppers were not forced to concentrate at streamside by the usual parching of their habitat away from the water. Still, it was not wasted effort to fish a fat hopper pattern during the breezy period that is the usual characteristic of a late summer afternoon.
It was not surprising that a size 14 Black Beetle could be counted on to fill quiet time between other surges of insect activity. And few were the days between July and late September that this Henry’s Fork staple was not called upon at some point.
To the dismay of early bow hunters, September was a mirror of August in terms of warm weather and the insects that kept trout busy through a bonus month of summer. Mahogany Duns were a nice addition to the menu as were Baetis that intensified as the days became shorter.

By October we were beginning to wonder when summer conditions would give way to temperatures that would activate fall instincts in the browns on the lower river and the big hybrids of Henry’s Lake. Despite minor turbulence, the weather remained quite pleasant through most of the month, and the fishing was fine. Well verified reports from the lake were so enticing that even Bob Evans was spotted tossing wet flies from shore near the State Park. Higher autumn flows on the river near Ashton had a subduing effect on the Baetis and Midge fishing, but the Brown trout ran rampant in their fall colors.
Perhaps made bold by deeper currents, it seemed that the large fish had declared war on big streamers as the weather began an abrupt change into winter mode.
A week into November snow and unseasonably cold temperatures hastened an early retreat from the trout battles for those of aging knees and arthritic hands. But my sadness was tempered by reflections on a remarkable year and a sense of optimism for what lies ahead.

While winter has thus far failed to deliver anything close to the massive snow fall of last year, 2011 ended with the water level of Island Park Reservoir standing at 83% of capacity. When combined with some tactful negotiation by the Henry’s Fork foundation, this abundant carryover will translate to winter flows of at least 500 cfs throughout the winter. As history has shown, a winter flow of this magnitude means more fish in the river for the coming year. And while nature is fully capable of throwing us a curve at any time, there is much to look forward to in 2012.