Data and code from: Home range shifts and habitat selection across life-history stages in grey partridges

Understanding how birds use space throughout the year is essential for
effective conservation planning, even in resident species. We investigated
seasonal space use in a Central European population of grey partridges
(Perdix perdix), a rapidly declining residential farmland bird. Using
radio-telemetry data from 201 individuals monitored between 2009 and 2017,
we estimated seasonal home ranges for three key life-history stages (pair
formation, breeding (i.e., nesting and early chick rearing), and winter).
We quantified spatial overlap and distances between consecutive seasonal
home ranges and analysed habitat selection during breeding and winter to
identify potential drivers of these shifts. Spatial overlap between
seasonal home ranges was generally low. In most individuals, core areas of
successive life-history stages showed little to no overlap, particularly
between breeding and winter, indicating pronounced seasonal shifts in
activity areas. Habitat selection at the home range scale differed
strongly between seasons: during breeding, partridges preferred fallows,
similar agri-environmental schemes and field margins relative to arable
land, whereas in winter arable fields were selected more. In contrast,
habitat selection at the telemetry-location level was more consistent
between seasons. Home range size varied with season and sex, with breeding
home ranges substantially smaller than those during pair formation and
winter. By quantifying spatial overlap between seasonal home ranges, this
study provides new insights into the spatial ecology of grey partridges.
Our results show that seasonal shifts in space use are likely shaped by
changing habitat requirements and that presence data gathered during pair
formation may not reflect breeding territories. Improving habitat quality
across the landscape may reduce the need for such shifts. More broadly,
our findings illustrate the importance of incorporating seasonal spatial
dynamics into conservation planning for farmland birds and other species
with seasonally changing habitat requirements.