- Species: Mayfly
- Size: 13-15mm (Size 10-12)
- Emergence: Mid August through mid September
- Emergence time: Late morning through mid afternoon
The Hecuba hatch in Montana is one of the most unpredictable hatches in the state. They’re a big insect, so when they appear, the fish are on them. But due to the nature of the Hecuba, they don’t establish every day.
Sometimes wading anglers feel it’s a guide hatch! In the Missoula area, it’s most prolific on the Bitterroot River, and will make a decent appearance on the lower Clark Fork River. You have to be in the right place at the right time, and a boat gives you a better chance of finding them.
Fly Fishing The Hecuba
Hecubas are well imitated by the Brindle Chute in a size 10-12. Additionally, a Hecuba cripple is an extremely effective imitation. The Hecuba may start as early as mid August, and appear through September. This is when the Brindle Chute really shines as a searching pattern, because the Hecuba is a big insect, appearing when food is scarce in the rivers. Even small numbers of Hecubas will get fish looking for them.
The nymphs are also sizable, and running a brown mayfly nymph or Umpqua’s Jig Pheasant Tail deep during this time of year is a very effective way to take trout. We don’t recommend devoting an entire fly box to the Hecuba, but make sure you have some when you head to the rivers in late summer.