It's hoped that the salmon death count in Ballisodare River has peaked.
It's estimated that nearly 1000 salmon are now confirmed dead as a multi agency investigation continues.
The nearby Owenmore River in Sligo and its tributaries have been closed for all fishing due to the ongoing outbreak of disease in the salmon population.
The State has closed the system until further notice.
Local Sinn Fein Cllr Thomas Healy says it's crucial that they get to the bottom of it as quickly as possible: