Habitat and space use of a rare woodpecker species

The project focuses on habitat use and breeding biology of the grey-headed woodpecker. We aim at investigating home range placement within forest landscapes, habitat preferences with in home ranges, and factors affecting home range size. Differences in forest habitat characteristics are examined by using existing habitat layers and remote sensing methods. Food composition is studied using metabarcoding of fecal samples. We also aim at recording nest and breeding success as well as annual survival of this secretive species as there are very limited empirical data on demographic rates.

Grey-headed woodpeckers are caught with mist nets using playbacks, colourringed and equipped with tiny radio transmitters. Tagged individuals are regularly located with a directional antenna. The transmitters further allow identification and regular controls of nest cavities, providing valuable data on the breeding biology. Resightings of colourringed individuals in subsequent years using playbacks allow for estimation of annual survival rates. Resource selection functions and digital habitat layers partly based on LiDAR data are used to investigate habitat preferences.

The population trend of the grey-headed woodpecker in Switzerland is alarmingly negative. This project will generate valuable knowledge about the habitat use of this rare woodpecker, which will enable target conservation measures to be developed for the species. The implementation of evidencebased conservation measures could give the rare forest dweller a chance to recover from its population collapse. By building cavities, the grey-headed woodpecker creates new breeding sites for secondary cavitynesting birds and is thus an important member of our forest ecosystems.

• Stiftung Yvonne Jacob
• Zigerli-Hegi-Stiftung