Red swamp crayfish, Louisiana crayfish	Status LU: isolated, first record: 2021
	Roude Suppekriibs	Status Eur.: established. IAS of EU concern (2016).
	Écrevisse de Louisiane	RA: ISEIA: A1, Black List.
	Roter Amerikanischer Sumpfkrebs	Wikipedia: | Wikispecies: | CABI
	Rode rivierkreeft	Back to the list of invertebrates

Report the species

→ Report Procambarus clarkii to the National Museum of Natural History.

Brief description

Procambarus clarkii (Girard, 1852) is a species of cambarid freshwater crayfish, native to northern Mexico, and southern and southeastern United States, but also introduced elsewhere, where it is often an invasive pest. P. clarkii is typically dark red, with long claws and head, small or no spines on the sides of its carapace just below the head, and rows of bright red bumps on the front and side of the first leg (Wikipedia contributors 2020).

The red swamp crayfish is most commonly found in warm fresh water, such as slowly flowing rivers, marshes, reservoirs, irrigation systems and rice paddies. It is considered to be the most ecologically plastic species in the order Decapoda, and is able to grow quickly even in only seasonally present water, being able to tolerate dry spells of up to four months. The red swamp crayfish grows quickly, and is capable of reaching weights in excess of 50 g, and sizes of 5.5–12 cm long. It is also able to tolerate slightly saline water, which is unusual for a crayfish. Additionally, P. clarkii are physiologically capable of tolerating relatively low dissolved oxygen concentrations. The average lifetime of Procambarus clarkii is five years (Wikipedia contributors 2020).

The burrowing activities of the red swamp crayfish can lead to damage to water courses and to crops, particularly rice, and its feeding can disrupt native ecosystems. It may out-compete the native crayfish species, and is a vector for the crayfish plague fungus Aphanomyces astaci, for crayfish virus vibriosis, and a number of worms parasitic on vertebrates. Their burrowing activities may also be a threat to civil infrastructure such as storm ponds and levees (Wikipedia contributors 2020).

Status and distribution in Luxembourg

The Louisiana crayfish was sighted in Luxembourg for the first time on 21 September 2021 in Lake Echternach. This discovery was made as part of the LUXIAS monitoring programme (a specific monitoring programme targeting invasive alien species) carried out by LIST (Luxembourg Institute of Science and Technology). In 2022, the ANF ran a trapping campaign using traps baited with fish pellets. Using 12 traps, a total of 267 Louisiana crayfish were caught between 26 August 2022 and 10 November 2022, including numerous egg-bearing females, females carrying larvae and juveniles. Currently (August 2026), Lake Echternach remains the only known location of the Louisiana crayfish in Luxembourg. An action plan relating to the species was published in 2024.

Risk assessment

ISEIA protocol

A1 (3+3+3+3) = Alert List (Ries et al. 2017: 68).

Harmonia+ protocol

Not assessed yet.

Worldwide distribution

Source: https://www.cabi.org/isc/datasheet/67878#toDistributionMaps

Bibliography

• CABI, 2019. Procambarus clarkii. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-13]
• MNHNL, iNaturalist & GBIF, 2020. Procambarus clarkii in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [accessed 2026-08-13]
• Ries, C., A. Arendt, C. Braunert, S. Christian, A. Dohet, A. Frantz, G. Geimer, M. Hellers, J. A. Massard, X. Mestdagh, R. Proess, N. Schneider & M. Pfeiffenschneider, 2017. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of invertebrates in Luxembourg. Bull. Soc. Nat. luxemb. 119: 63-70. [PDF 360 KB]
• Wikipedia contributors, 2020. Procambarus clarkii, Wikipedia, The Free Encyclopedia, 3 February 2020, 18:43 UTC, <https://en.wikipedia.org/w/index.php?title=Procambarus_clarkii&oldid=939000553> [accessed 2020-03-13]