Birdwatch Ireland has appealed to county councils to refrain from cutting hedgerows until November so that nesting birds will have a secure environment while rearing their young.
The voluntary environmental organisation is holding its annual all-Ireland conference on bird and habitat conservation in Ennis this weekend in conjunction with the Northern Ireland section of the Royal Society for Protection of Birds.
Mr John Murphy, BirdWatch Ireland's countryside officer, said complaints continued to be received last year of local authorities, including Limerick County Council and Tipperary North Riding Council, cutting hedgerows or issuing notices to landowners to trim roadside hedges at sensitive times of the year for birdlife.
"It is also a case for better instruction to hedge-cutting contractors on the timing and method of doing the work. Hedges are a vitally important habitat," he said.
The local populations of species such as blackbirds, thrushes, robins, wrens and finches were threatened by cutting back hedgerows between February and October.
Although the 1976 Wildlife Act protects hedges and other habitats from April onwards, there was "a long list of exemptions", Mr Murphy added, and the organisation was concerned at the slow progress of the Wildlife Amendment Bill through the Oireachtas.
When the Bill becomes law, it will give statutory protection to proposed National Heritage areas, which includes parts of the Burren.
This weekend, BirdWatch will be highlighting inadequacies in the Rural Environmental Protection Scheme in reviving threatened farmland bird spec ies such as the corncrake, the grey partridge and the barn owl.
Mr Murphy said other species such as yellowhammer, skylark, linnet, goldfinch, lapwing, and curlew, associated with non-intensive farming, were threatened by habitat destruction.
BirdWatch has submitted proposals to the Department of Agriculture for changes to REPS which would focus more on wildlife habitat protection.
Mr Liam Cashman of the legal services unit of the EU Commission's Environment Directorate will discuss the State's delay in designating Special Areas of Conservation under the EU Habitats Directive of 1992.