Species · GBIF taxon 8979506
Rusty Crayfish
Faxonius rusticusAlso known as Rusty Crawdad, Rusty Crawfish
Rusty crayfish are highly aggressive freshwater crustaceans recognized by the dark, rusty-red spots on each side of their carapace. They use their oversized, robust claws to defend against predators, dominate native crayfish, and uproot vast beds of aquatic vegetation. Their rapid spread across North America has dramatically altered lake and river ecosystems by reducing food and shelter for native fish.
InvasiveFreshwaterAggressive
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & prey
- Aquatic Plants
- Macroinvertebrates
- Fish Eggs
Predators
- Smallmouth Bass
- North American River Otter
- Great Blue Heron
ThreatsWater pollution, habitat degradation, and eradication efforts in invaded areas
HabitatsLakes, ponds, rivers, and clay-bottomed streams with rocky cover
Life span3 to 4 years
Size / weightNot available
Classification
- FamilyCambaridae
- SpeciesFaxonius rusticus
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Equipped with powerful claws that can deliver a painful pinch; handle with care if necessary.
- Why it is dangerous
- Possesses large, powerful claws capable of delivering a sharp, painful pinch that can break the skin of careless handlers.
- How to recognize a risky encounter
- Identified by the rusty-red patches on the sides of the carapace and black bands on the tips of the claws.
- What to do
- Pick up from behind the thorax to keep fingers out of reach of the claws, or use long forceps.
Responsible observation
- Identification: Look for the signature rust-colored spots on both sides of the carapace, just in front of the tail.
- Handling: Grasp the crayfish firmly but gently from the back of the carapace, just behind the claws, to avoid getting pinched.
- Prevent Spread: Never transport live crayfish between water bodies, and clean all boating gear thoroughly to prevent accidental introductions.
Competitor No machine-readable author provided. MikeMurphy assumed (based on copyright claims). / Public domain · cc0
Predator USFWS Mountain Prairie / Public domain · cc0
Close Relative Close Relative
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