The requirements of three co-existing woodpecker species Picidae in relation to forests' features in the agricultural landscape of SE Poland
The occurrence of woodpeckers in European forests depends on many forest stand characteristics. During the study conducted in 2013 in the agricultural landscape of SE Poland (in an extremely deforested area with a 5% share of forest area), the habitat requirements of Middle Spotted Woodpecker Dendrocoptes medius, Great Spotted Woodpecker Dendrocopos major and Syrian Woodpecker Dendrocopos syriacus were described. For this purpose, the degree of occupation by individual species of 73 forest patches was assessed over an area of 355 km2. To determine the habitat requirements of the woodpecker species, a set of 7 parameters characterizing the studied forests and their surroundings were determined, viz. forest patch area, average age of the tree stand, etc.). Generally, the Syrian Woodpecker inhabited small forest patches surrounded by a significantly larger proportion (2.3–5.6%) of orchards, compared to forests uninhabited by this species. The most important factors that positively influenced the occurrence of the Middle and Great Spotted Woodpeckers were the forest patch size, average age of the forest patch stand, and area of forest stands aged older than 80 years. The Great Spotted Woodpecker preferred forest patches with an area exceeding 15 ha, but the Middle Spotted Woodpecker occurred only in forest patches over 42 ha. Such minimum forest patch areas should be considered essential for protecting the two mentioned species in a heavily deforested landscape. Small-sized forest patches should also be protected, enabling refuge for the Syrian Woodpecker.
Keywords: bird conservation strategy, forest management, habitat selection, primary cavity nesters, rural landscape, woods, woodpeckers, SE Poland