Crayfish are freshwater relatives of the marine lobsters which they resemble closely. Species of crayfish can be found in many parts of the world with most species occur in North America (330 species) and Australia (100 species). There are seven European species including the White-clawed Crayfish which is the only species naturally occurring in Ireland. The populations of European crayfish have been affected by the impact of introduced mainly American species and disease (crayfish plague). The White-clawed Crayfish was listed on Annex II and Annex V of the Habitats Directive and the species is protected in Ireland under the Wildlife Acts. Ireland has international responsibility for the White-clawed Crayfish as it remains the only part of the EU with no introduced species of crayfish and no proven incidence of crayfish plague. The animal remains common in many lakes, rivers and streams in limestone districts. It is an important species ecologically both as a grazer of plants and as a favoured food item of the Otter.
White-clawed crayfish (Photo: NPWS)
NPWS has funded research on this species to look at monitoring methods for the species in lakes. Distribution data is also gathered to inform the Article 17 assessment.
Anyone intending to work on this species is required to obtain a licence from NPWS under Sections 22, 23 and 34 of the Wildlife Acts.