Fishing Report Updated April 25, 2021

This fishing report is valid from April 25 through the beginning of the spring runoff on the Yellowstone River, probably around May 10.

April weather has been pretty wild, oscillating between cold and snowy and warm and sunny, sometimes in the space of a single day. This has put a damper on the fishing, to be honest. More-stable conditions would help. That said, spring is springing and things are changing: more waters are fishable now, the fish are getting more aggressive, and runoff is closing in soon. One benefit of the oscillating and fairly wet weather we’ve had is that the decline in the snowpack has slowed. The upper Yellowstone Basin in Montana is still at 97% of normal snowpack. It will likely increase early this upcoming week before declining sharply late in the week when we have a few days of 70+ temperatures forecast. The spring runoff will begin then on rivers subject to mud like the Yellowstone, but the runoff will stall in early May, as the warm weather is not forecast to last.

The following rivers and water body types are now fishable and have had their individual reports updated as well (use the linkbox to your right on computer or the menu above on phone or tablet):

  • Yellowstone River
  • Lower Madison River
  • Boulder River
  • Stillwater River
  • Missouri River
  • Private Lakes
  • Large Montana Reservoirs
  • Paradise Valley Spring Creeks

The Yellowstone River is our top bet while it’s clear. Streamers have been most productive, but stonefly and mayfly nymphs and midge and BWO dries have also worked. The Mother’s Day caddis are not really hatching yet but they might at the end of the week. Certainly caddis larvae and pupae are worth trying as dropper nymphs.

The Lower Madison is mostly a nymph show: crayfish, San Juan Worms, and BWO nymphs are tops. Some BWO hatch activity is possible after lunch.

The Boulder and Stillwater Rivers are still too low to float but fishing well on nymphs. Fish a stonefly with a BWO dropper, or throw streamers. The streamer bite will improve as the water rises. The Stillwater will be high enough to float by the end of the week (a bit late, actually). The Boulder may not be quite floatable this week.

The Missouri River is fishing well top to bottom, though the Three Forks to Canyon Ferry stretch may get muddy this week. Below Hauser Dam (aka “Land of Giants”) will be quite crowded. Fish sowbugs and eggs, most with a pink cast. Some midge pupae fishing is possible, but rising trout will be rare. Below Holter Dam, the same flies will work, but the trout are also taking swung streamers, BWO nymphs, and perhaps midge and BWO on the surface.

Private Lakes are nearing their yearly peak fishing now. Large San Juan Worms and leeches are tops until mid-May, since the water is still cold.

Large Reservoirs will fish similarly to the private lakes, though they’re not quite so consistent yet, especially when it’s cold and windy.

The Paradise Valley Spring Creeks are fully booked right now, alas. BWO and midge hatches might bring up the fish. Eggs and San Juan Worms fished DOWNSTREAM of spawning areas will definitely work. Leave the shallow gravely spawning areas alone.

Relevant Montana Fishing Report Links