Red swamp crayfish

Procambarus clarkii


Photo credit: ©Trevor Renals
Procambarus clarkii
  • It is a red or red-brown crayfish, measuring up to 12 cm long, with a cylindrical body.
  • It has a granular carapace with marginal spines. Its chelae are long and narrow with bright red tubercles and spines.

Origin and Worldwide Distribution:
  • It is native to north-eastern Mexico and south-central USA. It has been introduced to Belgium, Cyprus, France, Germany, Italy, Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom.

Potential or Known Impacts:
  • It outcompetes the native European crayfish through transmission of the crayfish fungus plague Aphanomyces astaci.
  • It degrades riverbanks because of its burrowing activity.
  • It accumulates heavy metals and toxins produced by Cyanobacteria, and can transfer them to its consumers, including humans.

How could it get here?
  • Intentional introduced for aquaculture, but can spread also by anglers for local consumption, and as bait.
  • It is widely available in the aquarium trade.

Is it found in Ireland or Northern Ireland?
  • Not present in Ireland or Northern Ireland.

Methods for Prevention:
  • Monitoring and surveying pathways of introduction.
  • Removal of use for live bait.
  • Report any sightings. 

You can help by reporting any sightings:
Current Legislative Position (Listed on 03 August 2016)
  • This species must not intentionally be brought into the Union; kept; bred; transported to, from or within the United Kingdom, unless for the transportation to facilities in the context of eradication; placed on the market; used or exchanged; permitted to reproduce, grown or cultivated; or released into the environment.
For further queries, you can contact the Non Native Invasive Species Team in the Northern Ireland Environment Agency on 028 9056 9558.
Invasive Species Ireland

Invasive Species Ireland