Minister of State with Responsibility for Nature and Heritage Malcolm Noonan has described the setting of fires in recent days in mountainous areas as "appalling and unacceptable illegal behaviour".
Fires have been set in different parts of the country, including on the Blackstairs Mountains on the Carlow-Wexford border.
Yesterday, a number of units of Carlow Fire Service battled five significant gorse fires for nine hours on the mountains.
The fires were brought under control around 1am.
Under the Wildlife Act, it is illegal to burn land from 1 March until 31 August and individuals who set fires are liable to prosecution by An Garda Síochána and the National Parks and Wildlife Service.
Farm payments on illegally burned land can also be affected.
Mr Noonan said such fires have huge consequences for households, neighbouring lands, water and nature.
He said: "At this stage of the breeding season, birds are sitting on eggs and hatching. The destruction is heartbreaking.
"NPWS takes wildlife crime extremely seriously and staff have increased aerial "eyes in the sky" and ground patrols.
"They are also working on cross-compliance with the Department of Agriculture and will bring prosecutions wherever possible."
Acting Chief Fire Officer for Carlow Liam Carroll appealed to people to act responsibly and not cause heather and gorse fires.
He said: "Yesterday crews spent nine hours tackling these fires using beaters to beat out the flames.
"Apart from the environmental damage, it pulls fire crews away from urban areas where there is a risk to human life if fires occur.
"There is still a high danger for upland fires and also the possibility of fires spreading to forestery plantations of which there are a lot on Mount Leinster."
