Breeding bird communities in two Estonian forest landscapes: are managed areas lost for biodiversity conservation?

Abstract

To establish new reserves for biodiversity, the conservation value of currently managed forests should be assessed. I compared the bird fauna of a large reserve (Alam-Pedja) and an adjacent managed forest landscape in east-central Estonia. At 20-ha scale, managed forests had a denser and more species-rich bird fauna and as high abundance of species of conservation concern as the reserve. This was due to the higher small-scale diversity of vegetation types and a higher share of fresh-type forests in the managed area, since at the landscape scale, the species richness of the managed forest and the reserve were similar. Moreover, the species-area curves of the reserve and a combined sample of the reserve and the managed landscape did not differ, indicating that the latter added new species only due to enlarged area and not because of a distinct fauna. Thinnings changed community composition and tended to decrease species-richness. I conclude that managed forest landscapes are impoverished but still valuable for the conservation of forest birds in Estonia. Using the existing middle-aged or old unmanaged second-growth for new reserves seems to be an acceptable conservation strategy if the potential sites of conservation are immediately excluded from commercial use.