North Milk River

North Milk River Hatch Calendar

Last reviewed 2026-05-21

May hatches

No photo available

Water Boatman

Corixidae

Moderatemedium

#12-168-12 mm

Air 10–28°CWater 8–22°C

Midge

Chironomidae

Highmedium

#18-263-12 mm

Air -5–25°C (optimal 5–18°C)Water 2–20°C (optimal 4–15°C)

Blue-winged Olive

Baetis spp.

Highmedium

#18-225-7 mm

Air 8–18°C (optimal 10–16°C)Water 5–12°C (optimal 6–11°C)