Southern Ontario Hatch Chart

Mayflies

Hendrickson

Genus: Ephemerella subvaria
Hatch Period: late April - early May
Hatch Time: afternoon
Hook Size: 12-16

Early Blue-Winged Olive

Genus: Baetis spp.
Hatch Period: mid May - late May
Hatch Time: midday
Hook Size: 16-18

Pale Evening Dun

Genus: Ephemerella dorothea
Hatch Period: late May - early June
Hatch Time: evening
Hook Size: 18

Green Drake

Genus: Ephemera guttulata
Hatch Period: late May - early June
Hatch Time: dusk
Hook Size: 8-10

Brown Drake

Genus: Ephemera simulans
Hatch Period: late May - early June
Hatch Time: evening
Hook Size: 8-10

Mahogany Dun

Genus: Isonychia sp.
Hatch Period: early June - late September
Hatch Time: evening
Hook Size: 10

Light Cahill

Genus: Stenacron sp.
Hatch Period: mid June - late September
Hatch Time: evening
Hook Size: 14-16

White-Winged Black

Genus: Tricorythodes sp.
Hatch Period: early July - late July
Hatch Time: early morning
Hook Size: 20-22

White Fly

Genus: Ephoron leukon
Hatch Period: mid August - mid September
Hatch Time: evening
Hook Size: 14

Blue Winged Olive

Genus: Pseudocloeon sp.
Hatch Period: late August - mid September
Hatch Time: throughout the day
Hook Size: 22

Caddis

Spotted Sedge

Genus: Hydropsyche sp.
Hatch Period: early May - late August
Hatch Time: afternoon
Hook Size: 12-14

Little Black Caddis

Genus: Chimarra
Hatch Period: late May - early June
Hatch Time: morning
Hook Size: 18-20

Great Orange Sedge

Genus: Pycnopsyche spp.
Hatch Period: early - late September
Hatch Time: morning
Hook Size: 10

Stoneflys

Early Black Stonefly

Genus: Allocapnia sp.
Hatch Period: early April - early May
Hatch Time: midday
Hook Size: 16-18

Golden Stonefly

Genus: Paragentina media
Hatch Period: early June - mid July
Hatch Time: after dark
Hook Size: 8-10

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Contact us today to inquire about a guided trip on any of the great rivers in Ontario. You can call the shop at 905-689-0880 or using our guide trip inquiry form below. You can find out more about our services on our Ontario Fishing Guide Service page.