April in Montana can be cold, wet, and windy. But it can also provide some of the best hatches--and the best fishing--of the season.

On April 9th, we met our clients at the Bozeman airport. Assembled in the lobby of the airport were two dentists, a school administrator, and a tire-shop owner, and they displayed a collective look of terror as they stared through the windows at the snow falling at a rate of two inches an hour. The group then trudged through the snow to get to the trucks, as we explained (with game-show-host smiles on our faces) that the forecast called for sun and 65 degrees by the weekend. I don_t think anyone believed us.

With the smell of airline peanuts still fresh on their breaths, we hauled everyone straight to the Madison River below the Beartrap Canyon. Within an hour of their planes touching down, the anglers stood bundled in fleece and Gore-Tex in the middle of a blizzard, watching the heaviest Baetis emergence any of us had seen. The fish rose greedily for three solid hours that afternoon.

Thus began a five-day fly-fishing road trip across southwestern Montana in which we visited eight different rivers. Because of widely varying weather and water conditions, some rivers fished great, and others were simply unfishable. But we kept our plans flexible. When the wind blew a gale on the Missouri, we headed south to the Big Hole, the Beaverhead, and Poindexter Slough. When the Yellowstone muddied from warm weather, we fished Armstrong_s spring creek. Regardless of the conditions, we were able to find good hatches and fishing every day. And at the end of the trip, we drove back to the airport under blue-bird skies, with the windows rolled down.

Meteorology Lessons

Although the vast majority of traveling anglers visit Montana from July through September, April can offer some of the best fishing of the season. Every year, there is a brief window of time between the point when winter begins to release its icy grip and the beginning of runoff. This window of opportunity can last from four to eight weeks, during which the fishing experience is defined by heavy hatches, hungry fish, and few anglers.

However, you_ve got to get the timing just right. Planning and flexibility are crucial to springtime success. Anglers must be prepared to fish small flies, read low-water conditions, and deal with the occasional blizzard. Weather plays a key role in deciding which rivers to fish. In the course of one day, things can change dramatically, and the weather affects both the fish and the fisherman. A warm spell can mean a river that was fishing great the day before has turned muddy overnight. In addition, some rivers must be fished when it is cloudy and snowing, and others are best fished when the sun is shining.

There is a saying in Montana (as in many other places) that if you do not like the weather wait ten minutes, and this is never as true as it is in the spring. Weather conditions vary widely, from snow and air temperatures in the 20s one day, to warm and sunny short-sleeve weather the next. Even if a day starts out below freezing, you may end up shedding layers quickly by the afternoon. Despite, or perhaps because of the weather, the fishing can be good whatever the skies might foretell. Flexibility is the key. You must start each day by evaluating the weather conditions, sizing up the options, and heading out to the best river for that day.

Bright, sunny days are not ideal for heavy mayfly emergences, but will feature good early and late midge hatches and maybe some afternoon stonefly activity or a sparse Baetis emergence. By the end of April, an angler can start thinking about Mother_s Day caddis when skies are clear. These are the days to fish freestone rivers, such as the Big Hole, the Gallatin, the Clarks Fork, Rock Creek, and the Yellowstone. Western freestone streams present a multitude of possible places to find actively feeding fish. Insects will usually concentrate in foam lines, back eddies, or protected banks that are commonplace on these rivers.

Cloudy, snowy days are prime for great mayfly hatches, and it would be a wise angler who travels to a spring creek or tailwater, such as the Bighorn, the Missouri, the Madison below Ennis Lake, Poindexter Slough, or the Paradise Valley spring creeks. These waters are insect factories, producing hatches that will blanket the water and literally bring every fish in the river to the surface to feed ravenously for hours on end.

Location, Location, Location

Just before runoff starts in earnest, the rivers in Montana are as low and as clear as they are ever going to get, and the water slowly warms up as the spring season progresses. The fish react to the rivers_ moods each day, but trout are reluctant to relinquish the habits they employed to survive the long, cold winter. This means that the fish will hold where the water is warmest, out of the way of strong currents, yet still relatively close to good feeding lies. This is important to note, because locating the fish can be the most challenging part, especially on the large and intimidating rivers of Montana. If an angler knows that the long slow, pools, glides, and runs are the preferred holding water for the trout in the winter, he can concentrate on reading just the water in these areas.

Some stretches of water are easier to read than others, but the fish do tend to pod or concentrate heavily in these likely areas. Shallow riffles, pocket water, rapids, and shallow flats generally do not hold trout in the spring. An exception to this rule is when shallow flats are close to deeper runs. Sometimes, when a good hatch is in progress, trout will migrate short distances to feed lazily on emerging midges and Baetis, but as hatches wane, the fish will return to the deeper, slower water nearby.

Important Insects

As with any fly-fishing situation, you_ve got to know which bugs to imitate, so it_s important to have an understanding of the major hatches that occur during a typical Montana spring. The real stars are the diminutive, battleship-like Baetis mayflies. No other bug can match their intensity, sheer numbers, and tenacity. From early March on the spring creeks to mid-May on the freestones and tailwaters, under almost any weather conditions, an angler can run into some type of Baetis activity. On sunny days, expect a short, sparse hatch; on cloudy days, it is possible to encounter a monster hatch that can last for hours.

Fishing a Baetis nymph pattern just before the hatch is always a good idea. Generally speaking, Baetis will begin to come off at around 11:00 in the morning, and the hatch will hit its peak by 12:30. Frequently, the hatch lasts until 3 or 4 in the afternoon, but it can go even longer. If you are fortunate enough to wake up one morning and find those clouds hanging low, the temps hovering just above the freezing mark, and little to no wind, be prepared for tidal waves of olive gray mayflies emerging throughout the afternoon. [For more about Baetis mayflies, check out Rick Hafele's "Entomology" column on page TK-ed.]

Midges are the staple food item for early-season trout. There are hundreds of species of midges, most of which are yet unidentified, dispersed throughout Montana_s diverse rivers. Oftentimes, both midges and Baetis are on the water at the same time, and which bugs the fish prefer varies daily. However, midge hatches usually start earlier and last later, extending the hatch-matching opportunities by several hours. The larvae and pupae of these tiny bugs are just as important as the adults, and it is amazing how often the trout are focused on these barely noticeable insects.

Caddisflies begin to emerge by mid-April on freestone rivers, such as the Madison, the Yellowstone, the Big Hole, the Stillwater, and Rock Creek. The early season Brachycentrus caddisflies are nudged into activity by the increasing warmer days. The first caddisfly of the season is the most famous of all--the much heralded, but hard-to-find Mother_s Day caddis. Although you may first see these insects in mid-April, they normally don_t begin to emerge in fishable numbers before the end of the month. Warm afternoons and evenings are the best times to find these hatches, and if the weather cooperates, then this short but intense, activity will provide some of the best fishing of the year.

Several stonefly species can always be found lingering on the edges of the fishing possibilities. Because of the stonefly_s three- to four-year lifecycle, the ever-present nymphs are an occasional treat for early-season trout. Most trout foods are small during the early season, so when a juicy stonefly nymph rolls by, a trout will rarely pass it up. On top of the nymphing possibilities, a few stonefly species emerge in the spring, and they can provide limited but good dry-fly fishing as they return to the water to deposit their eggs. Skwala stoneflies provide the best activity, and they occur in good numbers on the Boulder, the Bitterroot, the Clarks Fork, the Big Hole, and Rock Creek.

March browns make an appearance on several waters--such as the Madison, Stillwater, Yellowstone, and Gallatin Rivers--giving anglers a brief glimpse at summer-size mayflies. These bugs are a solid size 14 and emerge in the mid-morning hours, often just before Baetis activity begins. When March browns are on the water, the fish seem to prefer them to anything else, but usually this hatch is unpredictable and sporadic at best.

A Smaller Selection

The two boxes of flies needed for spring fishing in Montana seem paltry in comparison to the truckload of boxes required to fish these same waters during the summer. There are fewer insects to match, but it_s extremely important that you have flies that match the specific springtime hatches, and that you have the right sizes.

You_ll need only a handful of nymph patterns, most of which can be fished in tandem with any of the others, or with a high-riding dry fly. Important patterns include the Bead-head Pheasant Tail (sizes 16 through 22), Shop Vac (sizes 16 through 20), Crystal Serendipity (sizes 16 through 22), Brassie (red, green, copper, and black, in sizes 18 through 22), and the venerable Black Girdle Bug (sizes 6 through 12).

Essential dry flies are the Baetis Sparkle Dun (sizes 18 and 20), Baetis DOA Cripple (sizes 18 and 20), black-winged Baetis DOA Cripple (sizes 18 and 20), and Baetis Foam Emerger (sizes 18 and 20). Midge patterns should be simple, and carrying a large range of sizes is more important than having dozens of different patterns and colors. Do not enter Montana without some Griffith_s Gnats (sizes 16 through 24), tied with and without shucks of brown Z-lon. These flies can be manicured on stream to fool the fish in most situations, on the off chance the trout don_t eat the original form of the G-Gnat to begin with. When the trout get finicky, tie on a Black Hatching Midge (sizes 18 through 24). Carry a few spent-wing midges for the spring creeks, the Bighorn, and the Missouri.

To match the Mother_s Day caddis, which ranges in color from dark olive to dark gray, use an X Caddis, Iris Caddis, or Elk Hair Caddis (all in sizes 14 and 16). If you encounter March browns, tie on a Sparkle Dun or a tan-bodied Parachute Adams (both in size 14). Stimulators (sizes 10 through 16) imitate the stoneflies on freestone rivers. Finally, for those times when there_s no hatch going on, add a handful of natural-over-pearl Zonkers, black and olive Flash-a-Buggers, brown Deer Hair Buggers, and Muddler Minnows (all in sizes 4 through 8) and your spring box is ready to go.

Montana_s spring fishing opportunities extend the season for the avid fly fisherman by at least a month. If you keep tuned into the Weather Channel each night and choose your waters wisely, you can enjoy great fishing on uncrowded waters. You might even experience some of the finest fishing you_ve ever had in Montana.

Steve Hoovler and Rowan Nyman are partners in Blue Ribbon Flies, in West Yellowstone, Montana. Combined, they have nearly 20 years of experience guiding in Montana. Each spring, they introduce more clients to the joys of pre-runoff angling. For more information, call Blue Ribbon Flies at (406) 646-7642.