THE SIGNIFICANCE OF PROTECTED AREAS FOR THE LAND BIRDS OF SOUTHERN FINLAND

Protected areas (nature reserves) cover 0.7% of the land area in south ern Finland (162,000 km2), which belongs to the south- and mid-boreal coniferous forest zones. The value of these areas in preserving land b irds was studied on the basis of quantitative censuses. The numbers of bird pairs were estimated in nature reserves and in the whole of sout hern Finland, and the significance of the reserves was evaluated based on bow large a proportion of the total population in southern Finland was found in them. Forest habitat generalists and species of conifero us forests occurred in protected areas as expected by the proportion o f these areas in southern Finland Specimens of these species groups co mprise two thirds of all the country's land birds. Species of old-grow th forests and open peatlands clearly preferred protected areas, where as species of bushes, and lush and deciduous forest were scarcer in pr otected areas than elsewhere in southern Finland The latter fertile ha bitats are poorly represented in protected areas, even though due to t heir disappearance or alteration elsewhere several species confined to these habitats have declined and are even threatened. Drainage of ope n peatlands and clear cutting of old-growth forests has caused a decre ase in the area of these habitats in southern Finland during the past decades. Therefore, protected areas have a high significance in preser ving bird species preferring these habitats. Protected areas are parti cularly important for decreased species of old-growth forests, such as the Three-toed Woodpecker Picoides tridactylus and the Siberian jay P erisoreus infaustus, as about 10% of their total population in souther n Finland was estimated to breed in protected areas. The future protec tion of both old-growth and deciduous forests is important if we are t o preserve biodiversity of land birds in Finland