Red Swamp Crayfish

The red swamp crayfish is one of the world's most successful freshwater invaders, at home in a Louisiana rice field or a canal in southern Europe alike. It grows fast, breeds fast, and can survive weeks in mud after its pond dries up.

Also known as: Louisiana crawfish; red swamp crawfish; Cambarus clarkii

It can be confused with other freshwater crayfish. Look for the row of bright red bumps running along its claws, a mark most other species lack.

It is typically dark red, with long claws and a long head. The sides of its shell, just below the head, have small spines or none at all. Rows of bright red bumps run along the front and side of its first pair of legs.

It lives in warm, slow-moving fresh water: rivers, marshes, reservoirs, irrigation canals, and rice paddies. It is native to the Gulf Coast and Mississippi basin in North America, but has spread to warm waters worldwide, including Europe, Asia, and Africa.

Not dangerous, but a large one can give a firm pinch. Do not move them between waters, as they carry a plague that kills native crayfish.

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  Signal Crayfish

  Pacifastacus leniusculus