A number of agencies are investigating a significant fish kill reported in Co Clare in recent days in which up to 2,000 fish have died.
According to locals, "hundreds of dead fish" were seen along a stretch of the Ballymacraven and Inagh rivers near Ennistymon.
Fisheries Environmental Officer with Inland Fisheries Ireland (IFI) Jane Gilleran said the incident was first reported by a member of the public last Tuesday.
Since then "we've discovered not just hundreds, but probably thousands of dead fish along a significant portion of the Ballymacraven River and into the bottom of the Inagh River," she said.
Speaking on RTÉ's Morning Ireland, Ms Gilleran said the fish involved include "eel, trout, salmon, rudd and flounder" and to see this number of eels dead, in particular, is "unusual".
"They tend to be a little bit more tolerant to pollution than trout and salmon, so it would highlight that it's been a very significant event that's come through.
"In terms of the cause, our investigations are ongoing and it's a little bit too early to kind of point or to be able to identify cause.
"We're waiting for water samples that we've taken to come back to us from the lab," Ms Gilleran added.
She said that "nothing on this scale has happened before".
Read here IFI's statement regarding fish kill in Co Clare: https://t.co/oyMnNKiUtO pic.twitter.com/Z3EYwVoIx4
— Inland Fisheries Ireland (@InlandFisherIE) May 8, 2023
"This is the most significant fish kill in my 16 years with IFI that I've been working in the Shannon and southern regions.
"In terms of the wider impact, obviously it has very significant impacts to the fish because we've lost probably the last three years of production of salmon.
"And as you know, salmon returned to the river that they were spawned in to spawn themselves, so potentially we've lost salmon.
"It'll have really significant long-term impacts for salmon on this stretch. And for eels.
"Eels are critically endangered species. There's less than 10% of what there was in the 1980s returning to Ireland, and we've lost all of the juvenile eels that have just returned from the Sargasso Sea. And right up to, you know, an adult female eel that's probably 15-16 years old."
Ms Gilleran added that "it's a difficult day for fisheries" to see this happen in a lovely stretch of river.
In terms of what can be done in the future to make sure it does not happen again, she said that involves continued monitoring and she asked everybody to be aware and mindful of the water that is leaving their premises.
"For members of the public, if they do spot anything like this to be our eyes and ears and report it to IFI," she said.
Instances of fish kills can be reported by calling IFI's confidential 24/7 number, 0818 34 74 24.
