Relationship between vegetation structure and abundance of Great-spotted Woodpeckers (Dendrocopos major) in a mosaic habitat

摘要

This study was made in a postglacial relic bog in the ócsa Protected Landscape Area in Hungary. Secondary succession of vegetation began after peat extraction and a grove-like forest evolved. Among the eight woodpecker species that occur in this area, the Great-spotted Woodpecker is the most abundant with the largest amount of data, it is for this reason we chose this species to study. The aims of this work were to detect changes in the abundance of the study species in relation to forest succession; to examine the seasonal patterns of these changes in abundance, and to identify any relationship between the height of the trees near the nets and the number of captured birds. We used the data from 1411 mist-netted Great-spotted Woodpeckers (1984- 2010), which were captured at the ócsa Bird Ringing Station (120 standard mist nets). The assessment of forest succession rates were based on aerial photos (1979-2010). We measured the height of the vegetation, at 12 points, near each 12 m long net. Population growth of Great-spotted Woodpeckers was significantly correlated with the rate of afforestation. The majority of birds occurred only during the dispersal period. The pattern of the captures correlated well with the vegetation structure, not just with height, but also with vegetation quality as well.