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Hatches › Crustacean
Pacifastacus leniusculus · species
Crayfish are a big, meaty year-round food source that can draw the largest trout and bass.
Category
Crustacean
Category
The insect or forage category for this profile.
Size
Typically about 2.4-3.5 in long, with larger individuals reaching roughly 6-8 in.
Size
Typical size range anglers imitate on the water.
Key stages
Eggs, Hatchlings, Juvenile, Subadult, Adult
Key stages
Life stages most relevant to fly fishing this hatch or forage.
Water types
Rivers, Streams, Lakes, Ponds, Reservoirs
Water types
Water types where this bug or forage is commonly found.
In Idaho, the common angler "crawdad" is most often the signal crayfish, Pacifastacus leniusculus, a freshwater crayfish native to western North America and associated with the Columbia River Basin. For anglers, it matters less as a hatch than as a substantial bottom-dwelling forage item that fish key on whenever they can pin one down.
Also known as: Crawdad
Female crayfish carry fertilized eggs under their abdomen, protecting them until they are ready to hatch.
From the eggs, tiny crayfish hatch. These hatchlings are miniature versions of adult crayfish.
Young crayfish grow through a series of molts, shedding their exoskeletons to increase in size.
After several molts, juveniles become subadults, continuing their growth and development.
Mature crayfish move from shallow areas to reside in burrows or under rocks in the stream bed.
Hatchlings
McFly Angler
Materials
Juvenile
Fly-Dressing
Materials
Subadult
Fliesbyaspeen
Materials
Adult
Svenddiesel
Materials
Crayfish
One species, multiple rivers.
5.0 MB · guide-to-idaho-crayfish.pdf
A comprehensive guide to the three types of crayfish found in Idaho watersheds - by Jim Ekins and Kim Holzer.
Source: University of Idaho
