Inland Fisheries Ireland is investigating a suspected fungal infection outbreak that may have killed up to 1,000 brown trout in the River Blackwater in Cork.

The organisation is currently assessing the impacted area, which spans an 8km stretch of the river between Mallow and Roskeen Bridge in Lombardstown. Inspections of the Allow and Minor Awbeg rivers have not detected the presence of infected or dead trout.

Inland Fisheries Ireland is liaising with Uisce Éireann, the EPA and Cork County Council to address the issue. Meanwhile, Marine Institute staff are supporting IFI as they undertake sampling to identify the possible infection. 

Anglers asked to refrain from fishing

IFI is urging anglers to refrain from fishing in the impacted stretch of river. They are also being advised to wash, clean and dry all equipment to avoid crossing catchments with tackle to minimise the risk of spreading infection. 

Investigations are underway to determine how the outbreak may have occurred. The probes, at this stage, have not yielded evidence of pollution. Monitoring and assessment of the river will continue to help identify the cause of the incident.

Weather may have had an impact

Freshwater fish are vulnerable to low water levels and high temperatures. Ireland has been impacted by hot and dry weather spells this summer, leading to the periodic closure of fisheries in the west in recent months.

Water levels are very low in the River Blackwater at Mallow, and water temperatures have been recorded at between 17-19 degrees.

IFI is urging the public to report instances of fish kills or suspected water pollution to its 24-hour confidential phoneline, 0818 34 74 24.