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Hatches › Stonefly
Pteronarcys californica · species
A huge spring stonefly whose migrating nymphs and egg-laying adults bring trout to the banks.
Category
Stonefly
Category
The insect or forage category for this profile.
Size
Nymphs commonly run very large and can exceed 2 inches; adults are likewise among the largest stoneflies anglers see.
Size
Typical size range anglers imitate on the water.
Key stages
Eggs, Nymph, Mature Nymph, Emerger, Adult Salmonfly, Mating Adults, Egg Laying Female
Key stages
Life stages most relevant to fly fishing this hatch or forage.
Water types
Freestone rivers, Fast runs, Riffles, Pocketwater
Water types
Water types where this bug or forage is commonly found.
Pteronarcys californica is the giant salmonfly, a large western stonefly in the family Pteronarcyidae and one of the most important hatch-matching insects in fly fishing. Its long aquatic life and dramatic shoreline emergence make both nymphs and adults high-value trout food.
Also known as: Giant Stonefly
Female Salmonflies deposit thousands of eggs on the water's surface. These eggs then sink to the river bottom, settling among rocks.
Salmonfly nymphs reside among rocks and submerged debris in the river, where they feed and grow for one to four years.
As nymphs mature and approach emergence, they typically migrate towards the river banks, often under the cover of night or in the early morning hours.
The nymph crawls out of the water onto rocks or streamside vegetation. Here, it sheds its exoskeleton to transform into an adult.
Newly emerged adult Salmonflies rest to allow their wings to dry and harden before they can take flight.
Adult Salmonflies mate in the air near the river or within streamside vegetation.
After mating, female Salmonflies return to the water to deposit their eggs, thus restarting the life cycle.
Nymph
Dressed Irons
Materials
Mature Nymph
Danie Erasmus (pgflyfisher)
Materials
Emerger
Caddis Fly Angling Shop
Materials
Adult Salmonfly
Fly Fish Food
Materials
Salmonfly
One species, multiple rivers.
1 angler found Salmonfly adult in the last 14 days. Reported from the Barbless app.
