Hatch Guide · Mayfly (Heptageniidae)

March Brown

March Browns are large, sturdy mayflies that emerge from fast, rocky riffles in May and early June.

Peak months: MayJune · now

Top fly patterns

1
March Brown fly pattern
Size 10-12 · dry
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Month-by-month activity

Number of rivers where the March Brown hatch is active each month.

Jan
Feb
Mar
Apr
May
10 rivers
Jun ●
Jul
Aug
Sep
Oct
Nov
Dec

Rivers where March Brown hatches

How to fish the March Brown

A size 10–12 March Brown, American March Brown, or Hare's Ear fished in or just below the surface film.

Frequently asked

When does the March Brown hatch?

Peak emergence: May, June. Timing varies by elevation, latitude, and water temperature.

What flies match the March Brown hatch?

Top patterns: March Brown (size 10-12).

What rivers have a good March Brown hatch?

March Brown hatches are documented on 10 rivers including: Farmington River, Housatonic River, Salmon River, Willimantic River, Deerfield River and 5 more.

How do I fish the March Brown hatch?

A size 10–12 March Brown, American March Brown, or Hare's Ear fished in or just below the surface film.

What is the March Brown?

March Browns are large, sturdy mayflies that emerge from fast, rocky riffles in May and early June. Family: Mayfly (Heptageniidae).

Related

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