More than 4,500 fish are suspected to have died in a fish kill in a Co Cavan river.
Officers from Inland Fisheries Ireland (IFI) observed “significant numbers” of dead trout, coarse fish and eels along a 2km stretch of the Cavan town river.
Brown trout, European eel, roach, lamprey and minnow, as well as freshwater crayfish, were among the species of fish found dead.
IFI received reports of the fish kill late on Tuesday and attended the site yesterday morning.
An interagency group including Cavan County Council, the Environmental Protection Agency, the Marine Institute, and the National Parks and Wildlife Service met yesterday to coordinate the investigation into the fish kill.
The group said it was too early to definitively establish the cause of the fish kill in the Co Cavan river.
In August last year, some 32,000 salmon and trout were killed in a major fish kill in Co Cork.
The fish kill occurred in a 37km stretch of the River Blackwater near Mallow.
The interagency group set up to investigate that fish kill could not identify a cause.
Separately last year, some 800 fish were found dead in Lough Sheelin in Co Cavan while another fish kill was reported on the Ballinagh River in Co Cavan.
IFI urged the public to continue to report fish kills, water pollution, habitat destruction or illegal fishing to its confidential 24/7 number, 0818 34 74 24.