Nymph · #134 of 532

Glo Bug

Also known as: Egg Fly, Yarn Egg

Imitates: Trout or salmon egg

Best Sizes: #10-14
Best Season: Fall (brown spawn), spring (rainbow spawn)
Best Conditions: Below spawning beds, tailwaters, Great Lakes tributaries
Water Temp: Any — eggs drift in all temps
Recommended Tippet: 4X-5X fluorocarbon

How to Rig It

Drift on its own under an indicator, or pair with a flesh fly or stonefly trailer.

How to Present It

Dead-drift through gravel runs below redds. Get it on the bottom — eggs roll, they don't swim.

Why It Works

When trout or salmon are spawning, every fish downstream — trout, char, whitefish — gorges on dislodged eggs. Few patterns out-fish a properly colored Glo Bug in those windows.

History

Developed in the 1960s on California's Sacramento River system as a steelhead pattern, the Glo Bug spread to every tailwater and salmon river in North America.

Pro Tip

Carry pink, peach, chartreuse, and orange. Fresh eggs are bright pink; older drifting eggs fade to peach and orange. Match the stage.

Frequently Asked Questions

Is fishing egg flies ethical during spawning?+

Avoid wading on or casting onto active redds. Fish downstream of spawning beds where eggs drift naturally and other species feed legally.

What color Glo Bug works best?+

Start with peach or pink. Switch to chartreuse 'Oregon cheese' when the bite slows or water is off-color.

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