Virile crayfish

Faxonius virilis · Aquatic life

Whole animal · Photo: Katrina Smith / CC BY

IntroducedCrustacean (crayfish, scud)

Also called Northern crayfish, Orconectes virilis, Crawdad

State listing

Oregon: Controlled

How to identify Virile crayfish

Medium to large crayfish up to about 5 inches
Broad, flattened claws with rows of yellowish or whitish knobs
Brown, olive or rusty body; claw tips often orange
No white patch at the claw joint

Similar species

Signal crayfish have smooth claws with a white to pale blue patch at the joint. Rusty crayfish have rusty spots on the sides of the back and dark bands near the claw tips.

Profile

Season	Active spring through fall.
Starts	Most active once water is above about 50 F
Depth	Shallow edges to moderate depths
How it spreads or reproduces	Walks between connected waters; moved by people as bait
Habitat	Ponds, lakes, reservoirs, rivers and canals with rocks or plant cover.

Why it matters in a lake

Non native in Idaho, where it is spreading in the upper Snake River drainage and Bear Lake and may help push out native crayfish; it is considered native east of the Continental Divide in Wyoming and also occurs in the Green River drainage. Oregon restricts all non native crayfish: live ones cannot be released, and they may be used as bait only in the water where they were caught.