Merlin The Merlin is a bird of open moorland during the breeding season, although in Wales pairs formerly bred on coastal dunes, sea-cliffs and dry lowland bogs. It is an elusive falcon and nests are often difficult to locate, although its habit of returning to the same area of moorland each year does facilitate the location of breeding pairs. It has suffered a long, steady decline throughout Wales since the turn of the century although there may have been a slight recovery since the 1980s as over half the Welsh population now breeds in old corvid nests on the edges of upland conifer plantations, often in traditional territories where pairs had apparently been absent for several years.