Pigeon and Poultry Breeders, Friends or Enemies of the Northern Goshawk Accipiter gentilis? A Long-Term Study of a Population in Central Poland
2019
Jakub Gryz | Dagny Krauze-Gryz
In this study, we focused on a goshawk population in central Poland (study area 105 km2, forests 24 km2, seven small forest complexes) which was monitored long-term (with high densities recorded in the 1980s of 16.3 pairs/100 km2 despite persecution by farmers) to analyse how environmental factors (prey availability and changes in the forest structure) influenced population abundance, breeding parameters, and diet composition. The study was undertaken from 2011&ndash:2018, and the results were compared with published data from two previous study periods (1982&ndash:1992 and 2001&ndash:2003). The number of breeding pairs dropped from 17.1 to 8.0: the breeding success was around 75% in all study periods. The selection of nesting trees followed the changes in stand species and age structure. More nesting attempts per one nest were recorded in the current time period (1.7 vs. 1.1), which probably reflected lower anthropopressure (i.e., no cases of persecution were recorded in this study). Diet composition seemed to follow changes in the prey availability: The share of domestic pigeons and poultry (the main prey in the 1980s) as well as small game dropped, while the share of Eurasian jay and wood pigeon increased. Our studies suggested that anthropogenic food (poultry and domestic pigeons) played a key role for the goshawk population in the transformed habitats of the field and forest mosaic.
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