When you’re fly fishing during the coldest months of the year, you have to consider more than midges and blue-winged olives if you want to catch trout.
[by Boots Allen]
Winter fly fishing is not for everyone.
The cold and snow and, to some, the apparent desolation, keep most anglers from many trout streams in North America during the shortest days of the year.
For those of us who do it on a regular basis, however, winter fly fishing has much to offer. Solitude is a big draw. So, too, is the chance of seeing wildlife rarely spotted in the summer months. The beauty of snow and ice on a pristine, wild waterway is an added bonus. Winter fishing also presents tantalizing challenges, and deciphering those challenges and putting a strategy together can be a lot of fun. The holding water where trout congregate from December through March can be significantly different from where they assemble during the rest of the year. The “sweet spot” during the day when trout are actively feeding, based primarily on water temperature, can vary from week to week and from one type of holding water to another. This is to say nothing about the challenge of just staying warm and keeping ice out of your rod guides.
I guide on and fish trout streams for about 40 days during the core winter months. Most of the anglers I fish with are well aware that targeting the right holding water is essential, and fishing during specific times of the day is more critical compared to the rest of the year. Most clients keenly focus on those principles, listen intently to my instructions, and constantly ask questions. That said, if there is one element I see anglers don’t focus enough on, it would be the patterns they have available and are prepared to fish.
The winter trout foods that most often come to mind are typically chironomids, blue-winged olives, or scuds, and for good reason. Midges are always active, even when water temperatures are at their coldest. When water temperatures warm into the low 40s (F), a common occurrence on trout streams in mid to late winter, blue-winged olives can appear with enough consistency you can time your trips to the river according to the emergence. And scuds or shrimp seem to be forever spewing from upstream dams on tailwaters all year long, including the winter when fish might be particularly attracted to such high-protein meals.
These food types are without question the most essential bugs of winter for most fly fishers. Nonetheless, there is other forage available during this time of year, and occasionally, imitating them can outperform the more common go-to patterns that mimic chironomids, Baetis, or scuds. Yet most anglers I guide or fish with during the winter are surprised I suggest using them—some scoff at the idea. After skeptics witness firsthand how well they produce, however, they’re quickly sold on the possibilities. It’s all just thinking outside the box at the most fundamental level.
I’ve found that when many anglers fish roe patterns, they’re typically thinking about imitating trout eggs, especially rainbows and browns. These fish spawn in the spring and fall, respectively. There is some variation among subspecies and from one stream to another, but for the most part, rainbows spawn from April to June and brown trout spawn from September to November.
What we are less likely to consider is the spawning of other fish that inhabit rivers where trout live. One of the most abundant species in the Western United States is the mountain whitefish. I have caught them everywhere from the Deschutes River in Oregon to the far eastern reaches of the Yellowstone River in Montana. In most states, these formerly designated “trash fish” are classified as game fish, and are late-fall to early-winter spawners, typically from late October and into December. Their spawning period overlaps part of the brown trout spawn on many waters, but many of us still quit using egg patterns by Thanksgiving and transition to midge imitations. The truth is, you can fish eggs productively through December because whitefish are still in the midst of their spawning season.
Whitefish do not spawn in the same manner as most trout. Instead of building nests, females will deposit roe directly onto stream bottoms that have sufficiently distributed gravel and cobblestone. The eggs become lodged amid various cracks and crevices. Males then sweep in and fertilize the roe with their milt, oftentimes before the eggs reach the substrate.
Because of the nature of this kind of spawning activity, the current sweeps away many eggs before they reach the bottom—sometimes hundreds at once. Drifting roe is readily available to trout, even to fish that are hundreds of feet downstream of spawning beds, and can create a perfect feeding frenzy under the right conditions.
In my part of the world, December can be an intense month for spawning whitefish. On the streams I guide and fish the most in December—Wyoming’s Snake River, the South Fork of the Snake, and the Henrys Fork in Idaho—the first two weeks of the month is a solid time for spawning whitefish activity, while during the last two weeks, activity tapers slowly. At that time I am fishing eggs as much as I am fishing standby midge imitations. I target the middle reaches and tails of riffles and seams and drift eggs through the lower half of the water column, no matter the depth of a particular run. The best part of going this route is that hookups can occur throughout the day, with as much action in the morning as there is in the afternoon.
I was completely ignorant of winter stoneflies until about 15 years ago. That was about the time that I began focusing on winter fly fishing. My conversations with 250-plus-day trout bums and noted entomologists around my home waters quickly made me understand the bug’s importance to trout, especially during the months of February and March. My fly boxes now include an ample selection of small stonefly patterns.
For anglers, winter stoneflies generally include two genera—Capnia, commonly referred to as the little black stonefly, and Nemoura, better known as the little brown stonefly. They are mostly associated with freestone streams, and are present on famed trout streams like Colorado’s Roaring Fork and Montana’s Yellowstone River. On streams I fish during winter, the first emergence occurs in mid to late February, and the word tiny is fitting. Most specimens are around 8 to 12 millimeters long and matched with a size 14 to 18 pattern.
A winter stone hatch is quite a sight. They often accumulate in high numbers—hundreds to thousands at a time—in slow, shallow water along banks and current margins. At times, you can observe stoneflies accumulate in shallow water at the inside head of a riffle. They then migrate, typically en masse, to exposed foliage and rocks where they then crawl from their shucks. This is generally an afternoon phenomenon, when water temperatures warm into the high 30s.
When fishing the winter stonefly emergence, use larva imitations during the gathering and migration described above. Target trout feeding in shallow water with minimal current, but be as stealthy as you can be so as not to spook fish that are already on alert from predators above. Use a lightly weighted imitation, especially in water no more than two feet deep with little to no current. The descent needs to be slow. One of my favorite patterns, Brackett’s LBS, sinks just fast enough after the material is saturated, but you can aid its descent with light tippet that can cut through the surface film. It’s not easy fishing, but the upside is you are sight fishing to cruising trout that are feeding in very shallow water. It’s exciting stuff.