Crayfish plague threatens to wipe out stock in Rathkeale's River Deel

“Thousands” of dead crayfish have been detected

Maria Flannery

Reporter:

Maria Flannery

Crayfish plague threatens to wipe out stock in Rathkeale's River Deel

Samples are being tested at the Marine Institute Fish Health Unit

A CRAYFISH plague which threatens to wipe out the species in Ireland has reached the River Deel in Rathkeale after its discovery in Tipperary in May.

“Thousands” of dead crayfish have been detected in Rathkeale, and river users are being urged to follow strict guidelines to prevent the spread of the plague.

There is concern that the disease, which is suspected to be the crayfish plague, will reach the main Shannon. While “it is not feasible to close off rivers”, the Department of Arts, Heritage and the Gaeltacht is requesting a voluntary ban on moving boats and fishing gear to other catchments.

“While the large kill of crayfish looks likely to be the crayfish plague, it has to be confirmed by laboratory analysis,” said a department spokesperson.

Samples are being tested at the Marine Institute Fish Health Unit.

“There is no known risk to humans or pets,” added the spokesperson.

The Department and Inland Fisheries Ireland is urging all river users where crayfish may occur  to implement strict cleaning routines.

“This is especially important as it is known that the crayfish plague organism can be carried on wet equipment to new sites. Containment of the outbreak is essential to prevent spread to other as yet unaffected populations in Ireland,” said the spokesperson.

“Anyone using the river is being urged to observe the Check, Clean and Dry protocol. All wet gear including keep nets and storage bags should be checked for any silt or mud, plant material or animals.

“It then should be thoroughly cleaned and finally dried. Disinfectant or hot water over 40C should be used to clean all equipment,  followed by a 48 hour drying period. This 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,” warned the department spokesperson.

People are also being asked to alert the authorities of any mass mortalities of crayfish and sightings of unusual crayfish, for example those with red claws or of a large size.

The white-clawed crayfish is a globally threatened species and Ireland holds one of the largest surviving populations. Until 2015, Ireland was considered free of the disease.

“If crayfish plague becomes established, there is a high probability that the white-clawed crayfish will be eliminated from much of the island,” said the spokesperson.