All Hatch Charts
Oldman River near Lethbridge
Southern Alberta · 6 active this month
Oldman River near Lethbridge Hatch Calendar
Last reviewed 2026-05-21
August hatches
No photo available
Pale Morning Dun
Ephemerella inermis
Moderatemedium
#16-188-12 mm
Air 14–28°C (optimal 16–26°C)Water 12–18°C (optimal 13–17°C)
No photo available
Yellow Sally
Isoperla spp.
Moderatemedium
#14-168-12 mm
Air 16–32°CWater 12–20°C
No photo available
Green Sedge
Rhyacophila spp.
Moderatemedium
#14-168-14 mm
Air 14–28°CWater 10–18°C
Midge
Chironomidae
Highmedium
#18-263-12 mm
Air -5–25°C (optimal 5–18°C)Water 2–20°C (optimal 4–15°C)
No photo available
Spotted Sedge
Hydropsyche spp.
Highmedium
#14-188-14 mm
Air 16–30°CWater 12–20°C
Grasshopper
Acrididae
Highmedium
#8-1215-35 mm
Air 15–35°C (optimal 20–30°C)Water 10–22°C