Concern has been raised by the infestation of Lough Corrib by a mussel which causes widespread damage to aquatic plant and fish life.
The Western Regional Fisheries Board confirmed that the fresh water zebra mussel has infested a substantial area of the lake in an area north of Oughterard.
Once it enters a lake system, the zebra mussel population multiplies quickly.
They can also grow so close together that they block off pipelines, and affect both water intake pipes and the generation of power by hydroelectric companies.
Zebra mussels are an invasive non-indigenous species that multiplies quickly and causes serious damage to aquatic plant and fish life.
The board confirmed the infestation after an investigation last weekend. The discovery was made during a trial to kill off another invasive non-indigenous species.
Speaking on RTÉ Radio's Morning Ireland, Greg Forde of the Western Regional Fisheries Board said the situation is very serious.
He said there is a perception that the zebra mussel cleans up water but the problem is that they ingest plankton, which other species need to survive.
Then they pump out nutrients that are not good for water quality.
While the presence of zebra mussels will not affect the water for humans, there are a lot of side-effects.
Mr Forde says this is an ecological change that is irreversible. The zebra mussels will more than likely grow into a population of billions in the Corrib because the water system is perfect for them.
