Glo Bug
When trout are gorging on eggs, nothing else comes close.
The Glo Bug is the definitive egg pattern — a ball of bright yarn on a hook that imitates the single loose eggs trout feed on voraciously during spawning season. Simple to tie and devastatingly effective, it is a must-have pattern from fall through early spring on rivers with spawning salmon, steelhead, or trout.
History & Lore
Egg patterns have been used for decades on Great Lakes tributaries and Pacific Northwest rivers where salmon and steelhead runs deposit millions of eggs. The Glo Bug, named after the bright Glo Bug yarn developed by Oregon fly tyers, became the standard egg imitation by the 1970s.
Variations
Nuke Egg
Smaller, more translucent version tied with McFlyFoam.
Y2K Bug
Two-tone egg with a bright dot center.
Sucker Spawn
Diffuse, veil-like egg cluster imitation.
How to Fish It
Dead drift the Glo Bug through spawning gravel and below spawning redds where loose eggs collect. Fish it with enough weight to keep it ticking along the bottom. It works as both a standalone fly and as part of a two-nymph rig above a smaller nymph.
When to Use
During and after salmon/steelhead/trout spawning runs — typically fall through early spring. Any river with spawning activity will have egg-feeding trout.
Materials
- Hook
- TMC 105 or Gamakatsu egg hook, #10-16
- Thread
- Uni 6/0, matching yarn color
- Body
- Glo Bug yarn, McFlyFoam, or similar egg yarn
Tying Video
Tying Steps
Start thread on a short-shank egg hook or scud hook.
💡 Egg hooks are designed to hide inside the round yarn ball.
Cut a 1.5-inch length of Glo Bug yarn.
💡 McFlyFoam and Otter's Egg Yarn are excellent alternatives.
Tie the yarn perpendicular to the shank at the midpoint, using 4-5 tight wraps.
💡 Fold both halves upward and take 2-3 wraps underneath to round the shape.
Pull all yarn fibers upward and trim into a ball shape about the size of a pea.
💡 Use sharp scissors and rotate the fly while trimming.
Whip finish under the yarn ball and cement the thread wraps.
💡 The thread wraps should be completely hidden inside the yarn ball.
Frequently Asked Questions
What size Glo Bug should I use?
The Glo Bug is most commonly tied in sizes 10–16. During and after salmon/steelhead/trout spawning runs — typically fall through early spring. Any river with spawning activity will have egg-feeding trout.
What does a Glo Bug imitate?
The Glo Bug primarily imitates salmon eggs, trout eggs, steelhead eggs. Dead drift the Glo Bug through spawning gravel and below spawning redds where loose eggs collect. Fish it with enough weight to keep it ticking along
What materials do I need to tie a Glo Bug?
Key materials include: Hook, Thread, Body. Tie a clump of egg yarn to the shank, trim it into a ball shape, and you're fishing. This is a 60-se
How do you fish a Glo Bug?
Dead drift the Glo Bug through spawning gravel and below spawning redds where loose eggs collect. Fish it with enough weight to keep it ticking along the bottom. It works as both a standalone fly and as part of a two-nymph rig above a smaller nymph.
Pattern Details
- Category
- Egg Patterns
- Sizes
- 10–16
- Colors
- Pink, Orange, Chartreuse, Peach, Yellow
- Weight
- None, Small bead for weight
- Hook Styles
- Egg hook, Scud hook
- Imitates
- salmon eggs, trout eggs, steelhead eggs
- Water Types
- freestone, tailwater
- Origin
- Pacific Northwest and Great Lakes tyers, 1970s
Buy This Fly
Buy at Fly Fish Food—
catches logged by anglers
Target Species
Effective on These Rivers
Available At
Pattern Details
- Category
- Egg Patterns
- Sizes
- 10–16
- Colors
- Pink, Orange, Chartreuse, Peach, Yellow
- Weight
- None, Small bead for weight
- Hook Styles
- Egg hook, Scud hook
- Imitates
- salmon eggs, trout eggs, steelhead eggs
- Water Types
- freestone, tailwater
- Origin
- Pacific Northwest and Great Lakes tyers, 1970s
Buy This Fly
Buy at Fly Fish Food—
catches logged by anglers