Inland Fisheries Ireland (IFI) is investigating a possible fungal infection outbreak that may have killed up to 1,000 brown trout in the River Blackwater in Co Cork.
IFI is currently assessing the impacted area, which spans an 8km stretch of the river between Mallow and Roskeen Bridge (Lombardstown).
Inspections of the Allow and Minor Awbeg rivers have not detected incidences of infected or dead trout.
IFI is liaising with Uisce Éireann, the EPA and Cork County Council, all of whom have had staff on the river throughout today.
Marine Institute staff are also supporting IFI and are undertaking sampling to identify the possible infection.
IFI urges anglers to refrain from fishing in the affected stretch of river.
Anglers are also being asked to wash, clean and dry all equipment, and to avoid crossing catchments with tackle to minimise the risk of spreading any possible infection.
IFI is investigating how a potential disease outbreak may have occurred. Investigations at this stage have not yielded evidence of pollution.
Monitoring and assessment of the river will continue to be undertaken to help identify the cause of the incident.
Water levels are very low in the River Blackwater at Mallow, and water temperatures were recorded between 17-19 degrees earlier this week.
Freshwater fish are vulnerable to low water levels and high temperatures.
Ireland has been impacted by hot and dry weather spells this summer, and these conditions have led to the periodic closure of fisheries in the west in recent months.
