Yn dilyn cyhoeddi rhaglen fridio gaeth yn Lloegr, pa gamau y mae Llywodraeth Cymru wedi'u cymryd i asesu effaith cimwch signal Americanaidd ymledol ar gimwch yr afon yng Nghymru er mwyn penderfynu a oes angen ymyriad amddiffynnol cydweithredol?
Work at a Natural Resources Wales’ hatchery began in 2008 investigating captive rearing techniques for white-clawed crayfish and the potential to introduce hatchery reared juveniles to ‘Ark' sites in Wales and the Marches. To date Natural Resources Wales have released more than six thousand captive reared white-clawed crayfish into six Ark sites.
The impacts caused by American signal crayfish on the native white-clawed crayfish are well known. They can grow and breed more quickly, are more aggressive and are tolerant of a wider range of conditions than the white-clawed crayfish, and therefore out-compete this native species.
American signal crayfish is defined as an invasive ‘species of special concern’ in GB. It is an offence to import, keep, sell, breed, transport or release this species into the environment. The Invasive Alien Species (Enforcement and Permitting) Order 2019 sets out the civil and criminal penalties for these offences.