Seasonal variation in home-range size of the White-backed Woodpecker

Abstract Knowing a species’ area requirements is fundamental for species conservation. For the nominate subspecies of the White-backed Woodpecker Dendrocopos leucotos , a species of high conservation concern in Europe, estimates of the seasonal and year-round area requirements based on telemetry are missing. In the present study, we radio-tracked adult White-backed Woodpeckers in Central Europe and investigated bi-monthly home-range sizes based on three home-range estimators in relation to season, sex, body weight, and year. Home-range size of 49 radio-tracked individuals varied depending on the used home-range estimator, with minimum convex polygons (MCP) and autocorrelated kernel density estimation (AKDE) producing 1.6–1.8 and 2–3.3 times larger seasonal home ranges than traditional kernel density estimation (KDE). Moreover, home-range sizes varied between seasons. Home ranges were smallest in February/March (predicted median home-range sizes ranged from 35 ha with KDE to 88 ha with AKDE) and April/May (KDE: 30 ha, AKDE: 55 ha) and larger during the rest of the year (KDE: 48–67 ha, AKDE: 136–184 ha). The mean home-range size of six individuals tracked in all seasons (calculated with all locations per individual) was 116 ha with KDE, 304 ha with MCP and 350 ha with AKDE. Our results highlight the importance of considering the full annual cycle when addressing area requirements of White-backed Woodpeckers and likely also of other species. Furthermore, our study shows that using multiple methods for home-range estimation may be useful to obtain results that are both comparable with those of other studies and capture the range in which the true home-range size is likely to be. For the conservation of the White-backed Woodpecker, we conclude that at least 116–350 ha of forest should be present for a pair.