White-clawed crayfish (Austropotamobius pallipes) - Species Action Plan

This is a lobster-like crustacean that grows to about 12cm (5 inches) long. They mainly live in clean flowing water and are mostly active by night. Crayfish
Ref 1/S12 Species Action Plan 12
Plan Author: Environment Agency
Plan Co-ordinator: Environment Agency
Final Draft 31 December 1998
Final Revised Draft February 2002


Action Plan Summary

Current Status

National Status

  • White-clawed crayfish is the only native species of freshwater crayfish in the UK. It is widespread in clean, calcareous streams, rivers and lakes in England and Wales and occurs in a few areas in Northern Ireland, but many populations have been lost since the 1970s. The species is listed in Appendix III of the Bern Convention and Annexes II and V of the EC Habitats Directive. It is classed as globally threatened by IUCN/WCMC. It is also protected under Schedule 5 of the Wildlife and Countryside Act in respect to taking from the wild and sale, and is proposed for addition to Schedule 5 of the Wildlife (Northern Ireland) Order 1985. 

Norfolk Status

  • White-clawed crayfish are found in the Rivers Wensum, Tat, Bure, Glaven and Yare. 
  • Recent survey data (eg Rogers and Holdich, 1997) indicate that the River Wensum and its tributaries hold the key populations of white-clawed crayfish in Norfolk. Crayfish are listed as one of the interest features for which the River Wensum has been designated a candidate Special Area of Conservation. Existing records suggest that native crayfish are frequent in the main river channel between the source and Swanton Morley, with fewer records for sites downstream. Tributaries of the Wensum with positive records for white-clawed crayfish include the River Tat, River Tud, Swannington Beck and Whitewater River. Detailed surveys of crayfish distribution within the Wensum catchment are currently underway (Autumn 2001). 
  • For the period 1990 onwards, there have also been positive records of white-clawed crayfish from the Rivers Yare, Glaven, Bure, Blackwater, Wissey and Scarrow Beck. Earlier records suggest that crayfish were once more widely distributed in the county. 

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Current factors affecting the habitat in Norfolk

  • The habitat requirements of this species are very vulnerable to modifications through the management of rivers and changes in water quality.
  • White-clawed crayfish are out-competed by non-native crayfish (eg Signal crayfish Pacifastacus leniusculus). In Norfolk, Signal crayfish are known to be present in the River Wensum, Reepham Tributary and River Yare. 
  • Crayfish plague is present in the county and affects the native species of crayfish only.

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Current Action in Norfolk

The Environment Agency has undertaken surveys of selected Norfolk rivers to establish the presence of white-clawed crayfish and non-native crayfish species.

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Action Plan Objectives and Targets


  • Attempt to maintain the present distribution of this species by limiting the spread of crayfish plague. 
  • Attempt to maintain the present distribution of this species by limiting the spread of non-native species. 
  • Attempt to maintain the present distribution of this species by maintaining appropriate habitat conditions. 


  • Maintain the present distribution of this species. 
  • Limit the spread of non-native species. 
  • Maintain and create appropriate habitat conditions.

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Key Contacts


English Nature

60 Bracondale, Norwich, NR1 2BE, Tel: 01603-620558 / Fax: 01603-762552 / Email: norfolk@english-nature.org.uk

DEFRA (RDS), Fisheries Division IIB (Aquaculture, Salmon and Freshwater Fisheries)

Room 308, Nobel House, 17 Smith Square, London SW1P 3JR, Tel: 0171-238-5931

Conservation Information

Rob Dryden, Conservation Officer

Environment Agency, Cobham Road, Ipswich, Suffolk IP3 9JE

Tel: 01473-727712 / Fax: 01473-724205 / Email: rob.dryden@environment-agency.gov.uk

Crayfish Farming


CEFAS Weymouth Laboratory, Barrack Road, The Nothe, Weymouth, Dorset DT4 8UB

Tel: 01305-206673

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Anglian Otters and Rivers Project (2000). The White-Clawed Crayfish. Anglian Otters and Rivers Project Fact Sheet No 7.

Environment Agency (undated). Freshwater Crayfish in Britain and Ireland.

Guan, R Z and Wiles, P R (1997). Ecological Impact of Introduced Crayfish on Benthic Fishes in a British Lowland River. Conservation Biology, 11 (3), 641-647.

Holdich, D M and Rogers, W D (1996). Government Action to Keep Signals on the Right Lines. Fish Farmer, 19 (4), 20-21.

Holdich, D M, Rogers, W D and Reader, J P (1995). Crayfish Conservation. R&D Project Record 378/10/N&Y, National Rivers Authority, Bristol.

Holdich, D M and Lowery, R S (1998) (editors). Freshwater Crayfish – Biology, Management and Exploitation. Chapman and Hall, London.

Lang, M and Wylde, A (2000). Some observations on surveying native and Signal Crayfish. British Wildlife 11(6): 398-400.

Peay, S (2000). Guidance on Works Affecting White-Clawed Crayfish. Report to English Nature and the Environment Agency.

Riches, J J (1999). The River Waveney Site No 2: Macrophytes and Invertebrates. River Waveney Chub and River Waveney Crayfish. Report to Environment Agency.

Rogers, W D and Holdich, D M (1997). Crayfish Surveys on the Rivers Wensum, Bure, and Gipping Catchments, sections of the River Yare, and the Rivers Stiffkey and Glaven. Report to Environment Agency and English Nature.

Smith, G R T, Learner, M A Slater, F M and Foster, J (1996). Habitat Features Important for the Conservation of the Native Crayfish Austropotamobius pallipes in Britain. Biological Conservation, 75, 239-246.

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