Cabin Fever Cure-April Fly Fishing on the Big Hole River

Many anglers overlook the fantastic fishing opportunities available before summer even begins. With Montana’s tourist season yet to kick off, the rivers remain quieter, making spring an ideal time for those seeking solitude. If you don’t mind temperatures ranging from 45-60 degrees, early-season fishing might be perfect for you.

The Pre-Runoff Advantage

From April to mid-May, the Big Hole River runs low with minimal fishing pressure and trout are eager to strike anything bigger than a midge. Spring hatches here include Skwala Stoneflies, Baetis, March Browns, Grey Drakes, and the Grannom Caddis—also known as the Mother’s Day Caddis, a hatch so dense that mouth breathers might find themselves choking on a few.

Currently, low-elevation snow levels are minimal, and in recent years, their melt hasn’t significantly impacted fishing. Higher-elevation snowmelt typically doesn’t come down until late May. As the second-largest undammed river in North America, the Big Hole always offers multiple sections to float. Some tributaries may rise during a warm spell, while others remain steady, making flexibility key.

A three-day, four-night fishing package is an excellent way to experience the best of these rivers. Our strategic location near the headwaters of the Missouri River provides access to the Madison, Big Hole, and Beaverhead Rivers, ensuring you’ll always find prime fishing conditions.

April Pre-Runoff Fly Fishing on the Big Hole River

The Big Hole River is one of Montana’s most diverse fisheries, featuring deep pools, undercut banks, wide riffles, and braided sections. Before runoff, the river runs low and clear, creating excellent wade fishing and precise casting opportunities. April is a prime time to fish this river, as trout become increasingly active with warming water and spring hatches.

River Conditions & Flow

Before runoff sets in, the Big Hole typically maintains lower, clearer flows—ideal for wade fishing and accurate presentations. Flow levels vary based on early spring weather, so checking streamflow reports before heading out is wise. Expect flows between 400-1,200 CFS in the upper and mid-sections. Warmer temperatures or early snowmelt can cause sudden increases, but for the most part, anglers can effectively target deep pools, undercut banks, and slower seams where trout hold before runoff shifts them into heavier currents.

Hatches & Fly Selections

April signals the arrival of key hatches, offering excellent dry fly, nymph, and streamer opportunities. Here’s what to expect:

• Skwala Stoneflies (Size 8-12) – One of the best early-season dry fly opportunities. Fish Skwala patterns near grassy banks and soft seams in the afternoon.
  • Top Patterns: Rogue Skwala, Bullethead Skwala, Stimulator (olive/tan)
• Blue-Winged Olives (BWOs) (Size 16-20) – Best on overcast days, these mayflies bring trout to the surface in slow runs and back eddies.
  • Top Patterns: Parachute BWO, Sparkle Dun, Comparadun
• March Brown Mayflies (Size 14-16) – Large and irresistible to trout, these mayflies emerge in late March and early April.
  • Top Patterns: Parachute March Brown, Purple Haze
• Caddis (late April, Size 14-16) – If temperatures warm enough, the early Mother’s Day Caddis hatch can create aggressive surface feeding.
  • Top Patterns: Elk Hair Caddis (tan/olive), X-Caddis

Best Tactics for April Fishing

1. Dry-Dropper Rigs

A Skwala dry fly paired with a nymph dropper is a deadly April setup, enticing trout to strike both above and below the surface.

• Best Combination: Skwala Dry + Pheasant Tail, Hare’s Ear, or Zebra Midge (Size 16-20)
• Pro Tip: Focus on shallow riffles and banks in the afternoon when Skwalas are most active.

2. Nymphing for Consistent Action

When dry fly activity is slow, a two-fly nymph rig with an indicator can be incredibly productive.

• Best Setup: Pat’s Rubber Legs (Size 8-10) as the lead fly, followed by a smaller BWO or midge nymph.
• Pro Tip: Adjust weight and depth based on current speed—trout will be holding in slower water near structure.

3. Streamer Fishing for Big Browns

April is prime streamer season for targeting large brown trout before runoff disrupts the river.

• Best Streamers: Olive/black Woolly Buggers, Sculpzillas, Sparkle Minnows, J.J. Specials, Yellow Yummies
• Pro Tip: Use a slow retrieve with occasional twitches in deep pools and along cut banks—cold water makes trout slightly sluggish, so give them time to react.

Weather & Fishing Windows

Montana’s April weather can be unpredictable, ranging from mild, sunny days in the mid-50s to sudden snowstorms with sub-freezing temperatures.

• Best Fishing Times: 10 AM – 3 PM, when the sun warms the water.
• Wading vs. Floating: Wade fishing is ideal in the upper and middle river sections, while floating is better for the lower Big Hole as it widens and deepens.

Final Thoughts

April fly fishing in Southwest Montana is one of the best-kept secrets in the angling world. With aggressive pre-runoff trout, reliable hatches, and fewer crowds, it’s the perfect time to experience these legendary waters. Whether you love dry fly fishing, nymphing, or throwing streamers, this window offers some of the best fishing of the year.

So, if you’re looking to shake off cabin fever—gear up and hit the water. Montana’s pre-runoff fly fishing won’t disappoint!