Flathead River Hatch Information2017-04-17T21:06:41+00:00

Flathead River Fly Fishing Hatch Chart & Fly Patterns

Flathead River Hatch Chart

Flathead River Fly Fishing Hatches

Due to it’s glacial influence, the Flathead is not known for it’s prolific insect life. It does get all of the western freestone insect hatches but slightly muted in numbers. The most note worthy hatches are probably caddis and PMDs in July, although hatches of less magnitude get plenty of attention from fish. Terrestrial fishing is king on this river. Ants, beetles, and hoppers come into play early here and reign supreme well into the fall. Small #16 – #18 sparkly ants are one of our favorite. Various color #12 – #16 attractors and foam variations are also great most of the year. Chubby chernobyls, PMXs, stimulators, and purple haze mayflies are our best selling flies for this river.

This information is a basic run-down of the hatch schedule for the Flathead River. Every Year is slightly different. Snow-pack, run-off, and weather conditions can alter the hatch times considerably. There are dozens of commercial nymph and dry fly patterns available for each individual insect. Although we tie a lot of our own flies, we have listed a few basic patterns that will help give you direction when purchasing or tying your own.

Hecuba Mayfly (Fall Drake)

Flathead River Skwala Eater

Flathead River Fly Fishing

Flathead River Fly Fishing Patterns

Midges #16-20 (Black & Green body, white wing)
Dry Fly – Griffiths Gnat, Poly wing midge, purple haze
Nymph – Brassie, Green machine, shop vac

BWOs – #16-20 (pale olive body grey wing)
Dry Fly – Para Adams, Para Haze, Sparkle, Dun, Marabou Cripple
Nymph – Pheasant tails, Green Machine, loop wing, Pheasant tail variations

Winter Stones #12-16 (dark brown & black body, dark grey wing)
Dry Fly – Sparse Dark Simulators
Nymph – Prince, copper johns, Epoxy back stones

Skwala #8-12(pale olive under body w/dark grey wing)
Dry Fly – Bullet heads, CDC Bullet heads, stimulators, Rogue Foam, Chubby Chernbyl, Foam variations
Nymph – Pats Rubber Legs, Double bead stones, Epoxy back stones

Caddis #14 &16 (tan, green, brown body w/tan wing)
Dry Fly – Elk hair, parachute elk hair, cdc
Nymph – Sparkle pupa, birds nest

Green Drake #8-12 Pale olive under body w/dark grey wing)
Dry Fly – Purple Haze, Para Adams, sparkle dun, Marabou Cripple
Nymph – Pheasant tails variations, loop wing

Sally Stones #14-18 (pale yellow and lime green under body w/light grey wing)
Dry Fly – Para hair wing, para cdc wing
Nymph – Epoxy stones, sally stone nymphs

Golden Stone #6-12 (golden yellow body w/medium brown wing)
Dry Fly –
Foam extended body, bullet heads, Chernobyl variations, stimulator, bugmeister, PMX
Nymph – Girdle Bug, epoxy back stone, double bead stone,

PMD #14-18(Pale yellow body with light grey wing)
Dry Fly
– Para Adams, Para Haze, Sparkle, Dun, Marabou Cripple, sparkle cripple
Nymph – Pheasant tails, Green Machine, loop wing, Pheasant tail variations

Mohagany Dun #12 – 16 (mohagany body w/dark grey wing)
Dry Fly – Purple Haze, Para Adams, Sparkle Dun, Sparkle Criple, Marabou Cripple
Nymph – Pheasant tail variations

Hecuba Mayfly / Fall drake #10 & 12 (tan/pale olive under body w/dark grey wing)
Dry Fly – Purple Haze, Para Adams, Sparkle Dun, Sparkle Criple, Marabou Cripple
Nymph – Pheasant tail variations

Terrestrials – Ants, Beetles, Hoppers, Moths (various colors and wing types)
Dry Fly – Foam Hoppers, Foam Beetles, Sparkle Ants, Bullet head hoppers, Para ants, para hoppers, Spruce Moth
Nymph – Drowned versions of all the above

Flathead River Fly Images

Blue Wing Olive

Yellow Sally

Green Drake

Golden Stone

Images in bottom row provided by Troutnut. Visit Troutnuts website to learn more about all of our insects.