Introduction to Fly Fishing Montana in Early Spring

Fly fishing Montana in early spring, from Late February or Early March through about May 10-15 (yep, late May is still “early spring”), has a great deal to offer visiting anglers. Crowds are minimal, the fishing can be outstanding, and with the possible exception of late autumn, it offers visitors the best shot at the largest trout of the year.

That said, it’s not for everybody. Yellowstone National Park remains closed to fishing until Memorial Day weekend, limiting opportunities to water outside the park. The weather can be awful, with heavy snow possible at all elevations throughout this period. The fishing, while productive, typically requires techniques that can be hard for beginner and novice anglers. Most of the fishing also requires nymphs and streamers, so dry fly fanatics will only have marginal opportunities. Last but not least, late in this period, the spring runoff begins on all freestone rivers (those without dams or a very sizable spring water component) and turns them into raging brown, unfishable torrents.

With the exception of the Missouri River, which is arguably at its best during this period, particularly for numbers of fish if not for dry fly fishing, all of the caveats in the last paragraph make early spring a poor choice for your first visit to the Yellowstone and southern Montana region. It’s a great choice for later visits, once you’ve “knocked the edge off” and are okay with somewhat more challenging and less consistent fishing, for the shot at one or two spectacular days.

Weather and Water Conditions

“Variable” is the only word that can describe weather and water conditions when you’re fly fishing Montana in early spring. It can be 75 degrees on the Missouri River in March, then snow sideways in late May in the same place. In fact, this wide variability is one reason I defined early spring as I did. By June 1, snow is unusual at low elevations (though it still occasionally falls). Before that, you had better come prepared to fish in the snow. Of course, if you bring winter clothing it will never get below 60 degrees, but that’s better than needing the winter gear and only having a tee-shirt…

To be more specific, throughout this period you must come prepared for any kind of weather, from warm and sunny with calm winds to torrential downpours or heavy snow, possibly accompanied by gale-force winds. If you come in March or the first half of April, it’s a good idea to bring ski gear in addition to your fishing tackle, because many of the ski areas in the region are actually at their best during this time, and all remain open until at least early April.

The water on the spring creeks always stays clear during this period (and all the time), but on freestone rivers including the Yellowstone, Boulder, and Stillwater, the water clarity and level can change drastically, even over a period of a few hours. Generally speaking, abnormally warm weather will raise water levels the next day, especially if this weather is accompanied by warm rain falling on high-elevation snow, while cold snaps can quickly drop levels and improve clarity, though water temperatures often nosedive and put the fish into a stupor.

On tailwaters, the Missouri and Lower Madison, flows generally increase more or less steadily during this period, as the reservoirs upstream are drawn down in preparation to hold the heavy snowmelt to come, but it is exceptionally rare for rivers of this type to get too muddy to fish, at least down to the first substantial tributaries downstream of the dams that control their flow. The Missouri, in particular, almost never gets too muddy to fish downstream of Canyon Ferry Dam, which encompasses the two great tailwaters (below Hauser and Holter Dams) which make this river great. Lakes generally remain frozen until sometime in late March (low-elevation lakes) to early May (high-elevation lakes). They are usually very good the moment they lose their ice.

The heavy spring runoff begins by the middle of May on all freestone rivers and streams. What is runoff? The spring snowmelt in the mountains (the valley snow melts in March and April and only dirties the water slightly, if at all). This high-elevation snow all melts in a rush and runs downhill and turns these rivers into chocolate torrents. This is not a case of “the fishing is going to be a little tough.” It’s a case of “there are full-grown trees and dead big game animals floating down the river at 10mph.” What were clear, pretty mountain rivers and streams a few days before are now raging, often flowing at many times their previous volume. The fishing is nonexistent, and it can be dangerous to even be on the water in a whitewater raft, due to all the debris in the water.

The Yellowstone River typically runs around 2,000 cubic feet per second flow on May 1, but at peak runoff near the end of May, it can be floating at 30,000, for example. The fishing is often quite good right before the heavy runoff begins, so it makes sense to try to hit the Yellowstone or Gallatin River just before the runoff starts, but you must have a backup plan in case you mistime things, because once the heavy runoff hits, the fishing is DONE on freestones until early summer. This applies to all freestone streams, large and small. All are out of play from sometime in early-mid May until at least the middle of June, and in some cases into early-mid July except during rare “runoff breaks” when brief cold snaps drop them back into shape for a day or two. Such breaks are rare and impossible to plan for.

Top Fisheries

Top fisheries in early spring within the Yellowstone Country Fly Fishing’s operations areas change as this period progresses. Early on, the Missouri, Paradise Valley Spring Creeks, and Yellowstone Rivers are your best choices. As early spring progresses, basically during the month of April, the Lower Madison and Boulder Rivers gets better and better and private ranch lakes and area public reservoirs experience ice-out and get red-hot right away, while the Missouri gets rather crowded even if the fishing remains great.

By late April or early May, the Yellowstone River begins seeing some bouts of early melt during warm spells and often goes out of play for a few days. These bouts get more severe and more common as spring progresses, so having a backup plan gets more and more important. The private lakes and spring creeks remain great nearby options, while the Missouri is great if you can stand crowded conditions. Sometime in the first ten days of May (roughly), the Mother’s Day Caddis hatch begins on this river. If the river has not yet entered the worst of spring runoff, this hatch can provide the best dry fly fishing anywhere in the region, with 100+ fish possible. This only happens about one year in three. The rest of the time, the river enters the heavy spring melt and becomes unfishable before the hatch really gets going.

Once the Yellowstone River blows out, the private lakes and the Lower Madison River are the best options within about two hours of our base in Livingston, with the Missouri and area low-elevation lakes also good choice.

My favorite fisheries in early spring are the Yellowstone River between Livingston and Gardner so long as it is clear, particularly in March when nymphing for pre-spawn rainbow trout waiting to run up tributary creeks can produce great fishing, the Missouri River except during the peak rainbow spawn around the beginning of May, and private lakes. Before mid-April, when access fees jump quite a bit, the Paradise Valley spring creeks are also very good.

Fishing Tactics

Fly fishing Montana in early spring is dominated by three events, all of which can interconnect: the rainbow trout spawn, all fish fattening up after a long, hard winter, and the first insect hatches of the season.

The rainbow trout spawn actually begins in February, but March and April are the most important months and the spawn can extend through May, particularly during high-water years on the Missouri River. While it is not ethical to target the fish as they are actually spawning, and I do not recommend it even if you see others doing so, fishing for pre-spawn and post-spawn rainbows as well as other trout feasting on the eggs of the spawners can be very good. Fish deeper water downstream of the mouths of small streams or downstream of areas of fine gravel on larger bodies of water. This is virtually all subsurface fishing. Use flies that look at least vaguely like eggs: egg patterns, pink scuds, and sowbugs and mayfly patterns that feature orange bead-heads.

When targeting pre-spawn or post-spawn rainbows as well as brown and cutthroat trout fattening up after winter, streamers are always good choices anywhere at this time, as are large San Juan Worms, while stonefly nymphs are good on all rivers that host these insects.

Until late April or early May, midges and Blue-winged Olives are the most likely insects to attract the trout. On tailwaters, you will seldom find vast numbers of fish rising to these insects, but when you do the fishing will be outstanding. On freestone rivers, you’ll often find a few fish rising each day, but almost never large numbers. On spring creeks, the hatches can be much more consistent, usually from late morning through mid-afternoon. Nymphing with patterns imitating these bugs is very consistent anywhere provided the water is clear, while on freestone rivers that are getting muddy, you’re better off with larger nymphs or streamers. By early May, caddis pupae and adult caddis are possible on all streams, but the best hatches in early spring occur on the Yellowstone (if it is clear). On lakes, midge and Callibaetis mayfly hatches are possible by early May, but the best hatches have to wait until late spring.

With the exception of tailwaters and perhaps spring creeks, where water temperatures do not vary throughout the day, it’s unlikely you’ll find good fishing early in the morning or late in the evening during this period. Instead, focus on the middle of the day and perhaps early evening if it’s warm. Insect hatches will be concentrated from late morning through about 4:00PM everywhere.

As you have hopefully gathered from the above, early spring IS NOT a great time for dry fly fanatics. There are some hatches, but the best fishing is with streamers and especially nymphs.

Who Should Think About Fly Fishing Montana in Early Spring?

Fly Fishing Montana in Early Spring is for experienced anglers who don’t mind fishing mostly or entirely with nymphs and streamers in order to target larger trout, either rainbows that are about to spawn or just finishing up or cutthroat or brown trout that are fattening up after a hard winter. Anglers willing to fish wherever weather and water conditions dictate, or even to go and do something else for a day or two if the weather is terrible for fishing, will have the greatest success.

Early spring IS NOT a good time for anglers wanting to fish Yellowstone Park (it’s closed to angling), beginners and novices, “dry-or-die” purists who won’t be happy stripping streamers or watching a bobber, or anglers who are dead set on fishing any specific body of water (with the exception of the Missouri River). It’s also a bad choice for anglers who can’t handle cold/wet weather without getting miserable.