Large numbers of dead freshwater crayfish were reported in the River Barrow in the stretch from Carlow to Graiguemanagh. It has been confirmed using DNA analysis that the cause of death was Crayfish Plague.
This is the fifth outbreak of the disease to be found in Ireland in the last two years.
It is feared that if the disease spreads further, then it will threaten the survival of the entire Irish population of this endangered species.
This worrying situation is being investigated by the National Parks and Wildlife Service (NPWS) of the Department of Culture, Heritage and the Gaeltacht, Inland Fisheries Ireland (IFI) and the Marine Institute.
In the meantime, anyone using the river is being urged to observe the Check, Clean and Dry protocol. All wet gear should be checked for any silt or mud, plant material or animals. It then should be cleaned and finally dried. Disinfectant or hot water (over 60C) should be used to clean all equipment followed by a 24hr drying period should be adopted as standard practice in all freshwaters. Drying is especially important, including removing of any water from inside a boat and disposing of it on grass. A drying period of at least 24 hours is needed to ensure that a boat is clear of infectious organism.
A White-clawed Crayfish. Photo: D. Gerke
People are also asked to alert the authorities of any mass mortality of crayfish or sightings of unusual crayfish that might be non-native species (e.g. crayfish with red claws, large size).
The full press release by the Department is accessible here: https://www.chg.gov.ie/crayfish-plague-spreads-to-river-barrow-and-water-users-are-urged-to-follow-biosecurity-advice-to-contain-outbreak/.