Red Swamp Crayfish, Procambarus clarkii

OTHER COMMON NAMES

Red swamp crawfish/crayfish, Louisiana crawfish/crayfish, mudbug

ETYMOLOGY

Procambarus = pro: early, first (Greek) + cambarus: genus of a related group of crayfish; clarkii: patronym of Clark, but unclear which Clark this refers to.

Ecology, Habitat, & Behavior

If you’ve purchased crayfish from a store or eaten them at a restaurant, chances are they were red swamp crayfish. The number of common names for this species is some indication of the relative importance, commercially and economically, of the red swamp crayfish. They’ve been farmed down in Louisiana since the 1700s, and have been introduced across the globe as pets and food. Outside of their native range they exploit various habitats, including swamps, rice fields, drainage ditches, lakes, reservoirs, and sluggish rivers. They are relatively tolerant of prolonged periods of drought, allowing them to be easily transported.

They are capable digging, producing burrows up to 3 feet deep. Their burrows irrigate soil, but can also cause damage to levees. Burrows are often occupied by more than one individual, and cannibalism can be a problem. Growth is rapid, and indviduals in communal burrows will molt in open water to avoid cannibalism (even if there are predators in open water). It is possible that they are capable of reproducing parthenogenetically (source).

QUICK FACTS

Avg carapace length: 1-1.5 inchesLife expectancy: 2-5 yearsAge at maturity: 2-4 months oldHabitat: Generalist, preferring habitats with fine sediment bottoms# of eggs: 100-500Diet: Omnivore (detritus, plant matter, and animals), juveniles eat relatively more animal matterNative or non-native: Non-nativeActivity pattern:

Nocturnal

Uses: Aquaculture, aquarium pets, bait

Life History Event Date/Season
Mating Fall and in warmer climates a second breeding cycle in the spring
Fertilization Delayed, sometimes in as short as 6 weeks, spring
Laying Eggs Spring
Hatch in 6-8 weeks
Can have 2 broods in warmer climates
Young detach from female 2 molts, up to 8 weeks

Key features for ID + similar species

Juveniles are not red and can be difficult to tell apart from P. acutus

  1. Dark red body
  2. F1 males have hooks on 3rd and 4th walking legs (as with P. clarkii)
ROSTRUM

Triangular, tapering to prominent acumen, lacking accessory spines.

COLOR/MARKINGS

Dark red, but somewhat dependent on habitat (darker in clearer water, lighter in more turbid water).

CHELAE

Narrow, with long fingers. Dactyls recurved.

AREOLA

Narrow or absent (obliterate) areola.

Range map for Red Swamp Crayfish

Range map based on observations from iNaturalist.org

General Research on Crayfish

  • NOBANIS: Invasive Alien Species Fact Sheet : source
  • Crayfish of the White River Watershed: source
  • Crayfish curriculum for educators: source
  • The Crayfishes of New England: source
  • Species of Ontario Crayfish: source
  • Lecture on Crayfish: video
  • Some aspects of the life histories of three closely related crayfish species, Orconectes obscurus, O. sanborni, and O. propinquus: source
  • Dictionary of crayfish names: source
  • Biological synopsis of the rusty crayfish: source
  • Observations on the life cycle of Procambarus acutus acutus in South Carolina culture ponds: source
  • Natural History of the two Crayfish of Northwestern Iowa, Orconectes virilis and Orconectes immunis: source

Crayfish of Vermont species profiles