Citizen science data confirm that expanding non‐breeding distributions of goose and swan species correlate with their increasing abundance

• DOI: 10.1111/ibi.13302
• Publication Date: 2024-01-04T10:48:52Z
• Authors: Henning Heldbjerg; Timme Nyegaard; Preben Clausen; Rasmus Due Nielsen; Anthony D. Fox
• Keywords: Breeding bird survey

We combined data from two independent Danish citizen science time‐series to describe changes in (1) abundance and (2) distribution of 12 wintering populations geese swans tested the hypothesis that increases national since 2003 correlated with an expansion into formerly unoccupied winter farmland habitat. Five showed significant abundance, declined remainder no trend over same period; nine (including five nationally increasing declining) significantly positive correlations between annual range size, including one stable population showing only local expansion. These results support our prediction key goose swan benefiting exploitation are greatest correlation Denmark. This implies continued growth these will lead their ranges, which not increase potential for agricultural conflict but importantly also geographical extent such conflicts.