Pacifastacus leniusculus

• The only species of Crayfish known from the Fraser Valley

• A problematic introduced species in Europe, Japan and California


Identification Tips:

• Looks like a small Lobster
• Up to 20 cm long, but most adults are 10-15 cm
• 10 legs on thorax
• White to blue patch at claw hinge (Like the white flags of a 'signal' person directing trains)
• Claws may be missing or different sizes

Life History:

• Female lays 200-400 eggs in the autumn; carries them under her tail until they hatch in spring
• Newly hatched juveniles cling to mother or several weeks
• Omnivorous; eats detritus on bottom
• May live up to 20 years
• Most abundant on rocky bottoms

Very SensitiveSomewhat SensitiveFacultativeSomewhat TolerantVery Tolerant
Pollution IndicatorHighly sensitive to pollution from metals, insecticides, herbicides and lampricides

Primary Information Source:
Voshell, J. Reese. 2002. A Guide to Common Freshwater Invertebrates of North America. McDonald and Woodward Publishing Company. Blacksburg, Virginia.