Sow Bug
The Sow Bug is an essential trout fly that imitates freshwater sow bug (asellus). It supports Sow Bug fly pattern, nymph fly for trout, and how to fish Sow Bug searches.
Imitates: Freshwater sow bug (Asellus)
Quick Reference
- Best Sizes
- #14-18
- Best Season
- Year-round
- Best Conditions
- Tailwaters (Bighorn, White, San Juan, Bow), spring creeks
- Water Temp
- 38-58°F
- Recommended Tippet
- 5X-6X fluorocarbon
How to Rig It
Drop 18-30 inches off a heavier anchor or under an indicator on tailwaters.
How to Present It
Dead-drift slow through the bottom third of the water column where sow bugs naturally tumble.
Why It Works
Sow bugs are 365-day-a-year food in tailwater systems — trout sip them constantly between hatches.
History
Tailwaters like the Bighorn made the Sow Bug famous. It's one of the cornerstone food forms in any limestone or bottom-release fishery.
Pro Tip
Carry gray, tan, and pink — the pink Ray Charles is deadly on the Bighorn in winter.
Frequently Asked Questions
Where do sow bugs live?+
Tailwaters, spring creeks, and limestone streams. Anywhere bottom releases keep water cold and stable they're a primary trout food.
What size sow bug should I use?+
Start with a #16 gray or tan. Drop to #18 in clear winter water; go pink in stained flows.
Not sure if Sow Bug is right today?
Get a fly recommendation based on live water temp, flow, sky, and time of day for any river in the US.
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