Red swamp crayfish
Procambarus clarkii
FAMILY
Cambaridae
TAXONOMY
Cambarus clarkii Girard, 1852, Texas, United States.
OTHER COMMON NAMES
English: Red crayfish, Louisiana crayfish; French: Écrevisse américaine, écrevisse de Louisiane, écrevisse rouge; German: Roter Amerikanischer Sumpfkrebs; Italian: Gambero americano, gambero rosso della Louisiana.
PHYSICAL CHARACTERISTICS
Body length to 4.7 in (120 mm). Claws long and narrow. Color dark red, sometimes nearly black; claws with bright red tubercles (small nodules) and red tips.
DISTRIBUTION
Native to the southern United States and northern Mexico. Widely introduced and now found in Europe, Africa, Central and South America, and Southeast Asia.
HABITAT
Sluggish streams, swamps and ponds, especially where there is aquatic vegetation and leaf litter. Most abundant in areas that are seasonally flooded. Tolerant of a wide range of conditions, including brackish water.
BEHAVIOR
Can dig burrows over 2 ft (0.6 m) deep to reach the water table during the dry season.
FEEDING ECOLOGY AND DIET
Omnivorous. Feeds on a wide variety of plants and smaller animals, including insects, snails, tadpoles, and small fishes.
REPRODUCTIVE BIOLOGY
Mature males occur in two forms. Form I is the sexually active stage, distinguished by enlarged claws, hooks at the base of some of the walking legs, and hardened gonopods. Following the reproductive season, males molt and revert to smaller-clawed Form II. Females store sperm and extrude eggs several weeks to months after mating. Eggs are brooded 2–3 weeks; there are no free-swimming larval stages, and the hatchlings are recognizable as small crayfish. The young may stay with the mother for several weeks. There are typically two generations per year. Lifespan is 12–18 months in the wild.
CONSERVATION STATUS
Not listed by the IUCN. An abundant species whose range is continually expanding due to intentional introductions and escape from aquaculture operations.
SIGNIFICANCE TO HUMANS
One of the most important aquaculture species, widely introduced throughout the world due to fast growth rate and tolerance of a wide range of conditions. Often raised in crop rotation with rice in the United States. Introduced into eastern
Africa to help control snails that host schistosome parasites. War emblem for the Houmas Indians. Commonly sold for home aquariums; also used as bait.
