The Significance of Protected Areas for the Land Birds of Southern Finland

Authors


  • Present address: Nature Conservation Research Unit, National Board of Waters and Environment, P. O. Box 250, FIN-00101 Helsinki, Finland

Raimo Virkkala

Abstract

Protected areas (nature reserves) cover 0.7% of the land area in southern Finland (162,000 km2), which belongs to the south- and mid-boreal coniferous forest zones. The value of these areas in preserving land birds was studied on the basis of quantitative censuses. The numbers of bird pairs were estimated in nature reserves and in the whole of southern Finland, and the significance of the reserves was evaluated based on how large a proportion of the total population in southern Finland was found in them. Forest habitat generalists and species of coniferous forests occurred in protected areas as expected by the proportion of these areas in southern Finland. Specimens of these species groups comprise two thirds of all the country’s land birds. Species of old-growth forests and open peatlands clearly preferred protected areas, whereas species of bushes, and lush and deciduous forest were scarcer in protected areas than elsewhere in southern Finland. The latter fertile habitats are poorly represented in protected areas, even though due to their disappearance or alteration elsewhere several species confined to these habitats have declined and are even threatened. Drainage of open peatlands and clearcutting of old-growth forests has caused a decrease in the area of these habitats in southern Finland during the past decades. Therefore, protected areas have a high significance in preserving bird species preferring these habitats. Protected areas are particularly important for decreased species of old-growth forests, such as the Three-toed Woodpecker Picoides tridactylus and the Siberian Jay Perisoreus infaustus, as about 10% of their total population in southern Finland was estimated to breed in protected areas. The future protection of both old-growth and deciduous forests is important if we are to preserve bio-diversity of land birds in Finland.

Abstract

Las áreas protegidas (reservas naturales) cubren 0.7% del área del sur de Finlandia (tamaño 162.000 km2) que pertenece a las zonas de forestas de coníferas sud- y mesaboreales. Se estudió el valor de estas áreas en la preservación de aves terrestres sobre la base de sensos cuantitativos. Se estimaron los números de parejas de aves en las reservas naturales y en todo el sur de Finlandia, y se evaluó la importancia de las reservas basándose en la proporción de la población total del sur de Finlandia que representaban las aves que se encontraban en las reservas. Generalistas de hábitats de forestas y especies de bosques de coníferas se encontraron en áreas protegidas tal como era esperado en base a la proporción de estas áreas en el sur de Finlandia. Los especímenes de estos grupos de especies comprenden dos tercios de todas las aves terrestres del sur de Finlandia.

Ancillary