Taxonomy
Astacus astacus | Noble Crayfish
Distribution
Status
Conservation status
Vulnerable
Legal status
Third Schedule listed species under Regulations 49 & 50 in the European Communities (Birds and Natural Habitats) Regulations 2011. (Note: Regulation 50 not yet enacted). Listed as a schedule 9 species under Articles 15 & 15A of the Wildlife Order (Northern Ireland) 1985 (Article 15A not yet enacted).
Invasiveness
Invasive species - risk of High Impact
Irish status
Absent
Introduction pathways - 1
Release in Nature
Introduction pathways subclass - 1
Release in nature for use
Introduction pathways - 2
Escape from Confinement
Invasive score
18
NAPRA Ireland risk assessed
Yes
Species Biology
Identification
Freshwater crustacean, generally dark brown to beige, though may be orange or even blue, less than 15cm in length with a red underside to the claws (Booy et al., 2015). Detailed guide to crayfish identification available at
www.biodiversityireland.ie/crayfish-identification.
Ecology
Unlike North American species of crayfish the noble crayfish is susceptible to the crayfish plague (Aphanomyces astaci) and is unlikely to be a source of introduction, unless diseased individuals are discarded into a waterway. The impact of Astacus astacus is likely to be through competition with the native white clawed crayfish (Austropotamobius pallipes) but it is difficult to assess how the mechanism of those impacts. This is a result of studies of competition in crayfish generally between North American species that are carriers but not affected by the crayfish plague and susceptible European species, such that the competition is highly asymmetrical.
Habitat
Inland surface waters
Reproduction
Age at sexual maturity may vary across its range but thought to be age 4 in females and age 3 in males and while fecundity varies with body length it is generally greater than 80 eggs per female (Abrahamsson, 1971).
Pathway and vector description
There is no natural means of the noble crayfish entering Ireland and accidental introduction in contaminated gear or as a transport contaminant are highly unlikely. The most likely pathway of introduction into Ireland is intentional release of crayfish into waterways, escape of live animals used as food or dumping of an aquarium specimen into a waterway.
Mechanism of impact
Competition
Broad environment
Freshwater
Habitat description
Found in any type of freshwater site
Species group
Invertebrate
Native region
Europe
Distribution
World distribution(GBIF)
Native distribution
Originally native to most of Central and Eastern Europe, from France to Scandinavia, it has been subsequently introduced into most of the neighbouring countries including the UK and is now present in virtually all of Europe with the exception of Iberia and Ireland (Edsman et al., 2010).
Temporal change
Records submitted to Data Centre in 2025
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How can you help
Report any sightings to the National Biodiversity Data Centre or Inland Fisheries Ireland. Practice good bio-security by disinfecting and thoroughly drying any boating, fishing, angling or other equipment that has been used in British or continental waters. Never release unwanted pets into the wild.
References
Publications
Booy, O., Wade, M. & Roy, H. (2015) A Field Guide to Invasive Plants & Animals in Britain. Bloomsbury. Edsman, L., Füreder, L., Gherardi, F. & Souty-Grosset, C. 2010. Astacus astacus. The IUCN Red List of Threatened Species 2010.