Stonefly · Aquatic insect
Salmonfly
Pteronarcys californica
Size
40–50mm
Hook size
#4–1/0
Hatch window
Season May–JulyPeak time 10:00–16:00
Water temperature
13° peak
10°16°
Hatches from 10°C, peaking at 13°C, tailing off by 16°C.How fish feed on it
Adult insects on the water are inefficient — a caddis skittering to lay eggs, a stonefly blundering about after crawling out, neither built for elegance. Trout treat it as an easy meal and a bit of theatre at once, chasing a moving fly with more enthusiasm than they'd ever give a still one. Movement is the tell; a static adult imitation often just sits there unloved.
Flies that imitate this
Chubby Chernobyl
Salmonfly
Ecology
Where you'll find this
- North America — WestPresent
Present throughout
Identification
Pteronarcys californica is a species of insect in the family Pteronarcyidae, the giant stoneflies and salmonflies. It is known commonly as the giant salmonfly .