Hatch Guide · Mayfly (Heptageniidae)

Light Cahill

Light Cahills are cream-colored evening mayflies that emerge from summer into early fall.

Peak months: June · nowJulyAugust

Top fly patterns

1
Light Cahill fly pattern

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Month-by-month activity

Number of rivers where the Light Cahill hatch is active each month.

Jan
Feb
Mar
Apr
May
3 rivers
Jun ●
14 rivers
Jul
7 rivers
Aug
Sep
Oct
Nov
Dec

Rivers where Light Cahill hatches

Farmington River Active now
Connecticut Active: Jun
Trout Management Area below Riverton — catch-and-release artificial-only year-round. Lower river sto…
Housatonic River Active now
Connecticut Active: Jun
Catch-and-release TMA between Cornwall Bridge and Boardman Bridge. Hatches: caddis, Hendricksons, su…
Deerfield River Active now
Massachusetts Active: Jun
Cold tailwater below Fife Brook Dam (Florida, MA) plus the Mohawk Trail water. Dam releases drive fl…
Battenkill River Active now
Vermont Active: Jun, Jul
Classic wild brown and brook trout river — no stocking, technical fish, clear water. Cooler than the…
Upper Delaware River Active now
Pennsylvania / New York Active: Jun
Big tailwater-influenced system (West and East Branches plus the main stem) holding wild rainbows an…
Beaverkill River Active now
New York Active: Jun, Jul
The birthplace of American dry-fly fishing. Classic Catskill freestone water with Quill Gordon, Hend…
Esopus Creek Active now
New York Active: Jun
NYC watershed tailwater — Tunnel Portal releases cold water from the Schoharie Reservoir, keeping te…
Penns Creek Active now
Pennsylvania Active: Jun
Limestone-fed wild trout stream famous for its Green Drake hatch in late May. Catch-and-release sect…
Brodhead Creek Active now
Pennsylvania Active: Jun
Historic Pocono trout stream. Wild and stocked fish. Good access throughout. Classic Hendrickson and…
Au Sable River Active now
Michigan Active: Jun, Jul
Michigan's most famous trout river — spring-fed, clear water through northern Michigan pines. The He…
Pere Marquette River Active now
Michigan Active: Jun, Jul
Blue Ribbon wild trout and steelhead river through northern Michigan. Spring steelhead and fall chin…
Watauga River Active now
Tennessee Active: May, Jun, Jul
Cold tailwater below Watauga Dam. Year-round fishery with strong sulphur, caddis, and yellow sally h…
Davidson River Active now
North Carolina Active: May, Jun, Jul
Gem of the Southern Appalachians in Pisgah National Forest. Wild trout in clear mountain water. Hatc…
Rose River Active now
Virginia Active: May, Jun, Jul
Remote wild trout stream in Shenandoah National Park foothills. Native brook trout in upper reaches,…

How to fish the Light Cahill

Fish the dun hatch in the last two hours of evening light with a size 12–16 Light Cahill parachute or comparadun.

Frequently asked

When does the Light Cahill hatch?

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

What flies match the Light Cahill hatch?

Top patterns: Light Cahill (size 12-16).

What rivers have a good Light Cahill hatch?

Light Cahill hatches are documented on 14 rivers including: Farmington River, Housatonic River, Deerfield River, Battenkill River, Upper Delaware River and 9 more.

How do I fish the Light Cahill hatch?

Fish the dun hatch in the last two hours of evening light with a size 12–16 Light Cahill parachute or comparadun.

What is the Light Cahill?

Light Cahills are cream-colored evening mayflies that emerge from summer into early fall. Family: Mayfly (Heptageniidae).

Related

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