Isonychia (Slate Drake)
Isonychia — also called the Slate Drake — are large, fast-swimming mayflies that hatch from late June through September. They swim to the bank before emerging.
Top fly patterns
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Month-by-month activity
Number of rivers where the Isonychia (Slate Drake) hatch is active each month.
Rivers where Isonychia (Slate Drake) hatches
How to fish the Isonychia (Slate Drake)
A size 10–12 Isonychia nymph or soft-hackle swung near bankside structure is deadly. On the surface, fish a White-Gloved Howdy or large Parachute Adams in the last hour of light.
Frequently asked
When does the Isonychia (Slate Drake) hatch?
Peak emergence: June, July, August, September. Timing varies by elevation, latitude, and water temperature.
What flies match the Isonychia (Slate Drake) hatch?
Top patterns: Isonychia / White Gloved Howdy (size 10-12).
What rivers have a good Isonychia (Slate Drake) hatch?
Isonychia (Slate Drake) hatches are documented on 8 rivers including: Farmington River, Housatonic River, Deerfield River, Battenkill River, Upper Delaware River and 3 more.
How do I fish the Isonychia (Slate Drake) hatch?
A size 10–12 Isonychia nymph or soft-hackle swung near bankside structure is deadly. On the surface, fish a White-Gloved Howdy or large Parachute Adams in the last hour of light.
What is the Isonychia (Slate Drake)?
Isonychia — also called the Slate Drake — are large, fast-swimming mayflies that hatch from late June through September. They swim to the bank before emerging. Family: Mayfly (Isonychiidae).
Related
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