Fisheries Board scientists are concerned about the discovery of an innocuously-named fern in a Lough Corrib catchment.
The reddish aquatic plant Azolla filiculoides, or Water Fern, has invaded a tributary of the River Clare that flows into the lough.
Invasive plant expert Dr Joe Caffrey of the Central Fisheries Board confirmed the finding after it was discovered last Friday.
The plant appears to be confined to a small watercourse less than 2km from Lough Corrib and has carpeted the surface of the watercourse concerned.
The hope is that the infestation can be contained and eradicated, because its attraction to quiet water means that it could colonise parts of Lough Corrib, backwaters and semi-enclosed bays.
The weed deprives the surrounding water of oxygen.
This infestation comes some five years after the discovery of Lagarosiphon major (pondweed) in Lough Corrib.
