It's early February and 39 degrees. The snow showers of an hour ago have transitioned to a wintery mix. We’re wet, but surprisingly warm. My friend, an Oregonian visiting Jackson Hole for the first time, quickly glances from the eddy seam he is fishing to catch a glimpse of the Tetons to the northwest. The shrouding cloud cover dims any hope for a sighting. I assure him they’re still up there. His gaze returns to the tandem midge rig at the end of his leader. Cutthroats continue to dimple the surface around his flies. A half dozen have been brought to the net. We are looking to double that number.
Winter fishing in this part of the West is a relatively new phenomenon. Prior to 2004, Wyoming’s Snake River and the South Fork of the Snake in Idaho were closed during the core snow months of December through March. Sure, it was officially open for those casting to whitefish, and some used that as a guise for going after the trout they were actually targeting. But this was fewer than a dozen or so resident anglers. Game and Fish signs reading “Closed to Fishing” were more than enough to keep folks off the water. April 1st was opening day on the Snake in Wyoming. It was Memorial Day weekend on the South Fork.
The past 15 years have been a learning experience for those of us now fishing these streams year round. We knew there would be opportunity with midges like everywhere else trout live. However, we discovered that the latter half of February brought an impressive emergence of tiny winter stoneflies (Capnia). The whitefish spawn of late autumn meant that roe patterns could be fished with production well into December, especially on the South Fork. We also proved what fishery managers had known for decades – the reduction of habitat on Snake River tributaries, an event that occurs during the winter months due to declining flows and the freezing of significant portions of smaller streams and creeks, leads to an influx of juvenile trout and forage fish in the main river. As a result, fishing the Snake in February and March with small streamers can be solid.
Those unacquainted with winter in “Wydaho” immediately envision sub-zero temperatures and snow drifts in the three to four foot range. While these events can certainly happen, they are actually a rarity. Winters here, like everywhere in the Rocky Mountain West, are getting warmer. The data I've collected over the past dozen years show an average of 11 days each winter when overnight temps are below zero. In fact, a case can be made that we have more days over 40 degrees than lows in negative territory. Most days we are shedding layers. And while Jackson Hole Mountain Resort averages over 450 inches of snowfall at the 10,000 feet level, the valley floor (6,200 feet) receives less than 65 inches. For a good part of the winter, we are walking on dry cobblestone banks.
There are times when both visiting and local fly fishers raise concerns about the detriment we may pose to our trout by fishing for them during the heart of winter. Some claim that these four months are the only respite fish get from those tiny imitators with sharp metal sticking out of them. Other suggest that our spring spawners – cutthroats and rainbows – need the rest before they make their violent, energy draining run up tributaries to lay eggs and deposit milt. “Shouldn’t the river remain closed?” they ask.
I cast to these trout year all 12 months of the year. If there is one time when it makes sense to fish for them and do minimal damage it is unquestionably winter. The cold water, often under 40 degrees, is saturated with oxygen. As long as you submerge your hands, cooling down their temperature close to that of the water you are fishing, recovery is almost guaranteed. This includes those fish that will be spawning in a couple months. Even more, not all trout on our rivers will spawn every year. Many have not reached full sexual maturity. Others are long-lived gargantuan fish that no longer spawn. And still others – particularly brown trout on the South Fork – will not be spawning until autumn. Pressure is even less of an issue. I have fished throughout the West and I can say with confidence that we have some of the least pressured water available, even in the summer months. And these are streams with 1,800 to 6,000 trout per mile.
If there is one time of the year that our rivers should be closed to fishing, it would have to be August and September. Fishing during these months are amongst the most consistent found anywhere, especially with dry flies. It is also when our water temperatures are peaking in the high 60s. Oxygen is greatly depleted. There are days in late August where I handle trout that are pulsating with heat. I have no doubt released fish that died. This is happening seemingly everywhere that trout reside. Precautions are taken, of course. We start a hell of a lot earlier than we did 30 years ago and are trying to finish up by 4:30pm, when our water temps start to peak. Fish are kept in the water as much as possible after landed and if a fly is deemed to be too difficult to retrieve in a short period of time, it is cut from the leader and left to dislodge on its own.
But fat chance that my waters will ever be closed in August. And by no means am I advocating for it. Fly fishing is a significant industry in Wyoming and Idaho, bringing employment and additive revenue to our tourist economy. But just as important is the fact that fly fishers would rather be on the water when it is 85 degrees that when it is 42 degrees. The action can be just as good, but it might be just a little too uncomfortable. And most anglers, whether they want to admit it or not, have a disdain for discomfort.