The National Parks and Wildlife Service (NPWS) has said that it is investigating what it called a "significant" fire incident at Barley Cove, on the Mizen Head Peninsula in Co. Cork.
The fire occurred on Sunday evening (February 9), and affected a special area of conservation (SAC), the NPWS said.
The service said it responded quickly, following the report of the fire, to assess the damage. Initial estimates suggest that approximately 150ha of land within the SAC were affected.
Special areas of conservation are areas set outside for nature and wildlife in Ireland, as designated under the EU Habitats Directive. Some farming activities require special permissions on these lands that are not required on undesignated areas.
The NPWS said it is conducting extensive surveying and mapping of damage to the area using aerial and ground surveillance.
The service said it is also gathering evidence from the damage and conducting door-to-door enquiries as part of an investigation for a possible prosecution.
The NPWS will cross-report any identified breach of the law to the Department of Agriculture, Food and the Marine, and a sanction may be applied to persons deemed to be responsible (if they are a farmer) for the fire under the conditionality for area-based payments under the Common Agricultural Policy.
The service said this would be the case in any such investigation of this type.
Commenting on the investigation, Minister of State for nature, heritage and biodiversity Christopher O' Sullivan said: "Illegal and uncontrolled fires cause irreplaceable damage to wildlife, habitats, and environment, puts our communities at risk, and also causes unnecessary pressure on our emergency services.
"Our special areas of conservation protect nature and wildlife in those places where our most treasured and vulnerable species live and make their homes. Aerial surveillance carried out by the NPWS at the scene indicates extensive damage within the SAC to the upland and heathland habitats," he added.
"An investigation is underway and I'm appealing to the public to come forward with any information that may be of assistance," the minister said.
Niall Ó Donnchú, director general of the NPWS, said: "These incidents pose a serious threat to our biodiversity and we have invested in our capacity to respond quickly when they occur. We are working closely with the Gardaí on this investigation and are collaborating with them to tackle wildlife crime throughout the country."