Black Gnat
Imitates: Small black terrestrials, midges, and dark caddis adults
Quick Reference
- Best Sizes
- #12-18
- Best Season
- Spring through fall, especially after rain
- Best Conditions
- Small streams, slow pools, after rains when terrestrials wash in
- Water Temp
- 50-68°F
- Recommended Tippet
- 5X-6X mono
How to Rig It
Fish wet on a swing or dead-drift just under the surface. Dry version exists as well — match the activity you see.
How to Present It
Down-and-across swing through pools and runs, or dead-drift the dry through risers eating small dark adults.
Why It Works
Small dark silhouettes are universally trout food — the Black Gnat covers everything from drowned ants to small dark caddis with one impressionistic outline.
History
One of the oldest documented fly patterns in angling history, mentioned in British texts dating back to the 1600s. A pattern that has outlasted entire schools of fly design.
Pro Tip
Never leave a fly box without a few small Black Gnats. After a summer rain, when ants and beetles get washed into the river, this old wet fly outfishes much fancier patterns.
Frequently Asked Questions
Is the Black Gnat a dry or wet fly?+
Both versions exist, but the original and most useful is the wet fly. It imitates drowned terrestrials and small dark adults equally well.
How old is the Black Gnat pattern?+
It dates back to at least the 1600s in English angling literature, making it one of the oldest fly patterns continuously fished.
Not sure if Black Gnat is right today?
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