The Northern Ireland Environment Agency (NIEA) is continuing to assess the extent of damage caused by a pollution incident on a tributary of the Moyola River in Co Londonderry.
A number of dead fish were discovered on a stretch of the Altagoan River, near Draperstown on Friday, November 11.
It’s understood the fish kill occurred after slurry was discharged into the waterway.
A spokesperson for the Department of Agriculture, Environment and Rural Affairs said the joint investigation into the incident, involving NIEA and Inland Fisheries staff, will continue over the weekend.
The spokesperson said it’s not yet known how many fish were killed, but she confirmed that investigators have “traced the pollutant back to source” and are “continuing to take statutory samples and gather evidence.”
The fish kill has angered local anglers, who have stressed that the pollution incident has destroyed a lot of the enhancement works they’ve carried out on the river in recent years.
A post on the Moyola Angling Association Facebook page said: “The discharge occurred on the Altagoan River, near Draperstown in County Londonderry, which is a major tributary of the Moyola River flowing from the Sperrin Mountains into Lough Neagh.
“The Moyola is a major game fishery with Salmon, Brown Trout and Dollaghan Trout and there is evidence of a number of fish being killed by this effluent discharge. In addition to the death of mature fish many fish fry and invertebrate life, on which the fish feed, will have been destroyed.
“Fisheries protection officers and members of Moyola Angling Association have been on site this afternoon monitoring the damage caused by this incident.”
One local angler commented: “Absolutely disgusting. All the hard work is going to be undone.”