Pigeon and Poultry Breeders, Friends or Enemies of the Northern Goshawk Accipiter gentilis? A Long-Term Study of a Population in Central Poland

The population of goshawks crashed in the middle of the 20th century due to persecution, forest management practices, and the usage of toxic pesticides (DDT) in agriculture. Now, it has rebuilt, yet the population trend is not equal across countries. Here, we focused on a goshawk population in central Poland for which monitoring started in the 1980s (high densities were recorded at that time of 16.3 pairs/100 km2) to see how changing environmental factors influenced the current population trend. In the field and forest mosaic, these birds build their nests in small forest complexes, but important prey tend to be caught near farmsteads. This has previously resulted in the persecution of the birds by farmers. Anthropogenic food (poultry and domestic pigeons) played a key role in their population density. Consequently, when the anthropogenic food base was limited (due to changes in the Polish farmland), population abundance dropped by half. As supplementary prey (including small-game and most corvid species) were not abundant, goshawks could not replace their staple food of anthropogenic origin. This demonstrates the complex way in which socioeconomic changes in agriculture can influence a raptor population: both positively (fewer cases of persecution are being recorded now) and negatively (small-scale breeding of pigeons and poultry became unimportant and unprofitable, and small game abundance decreased due to changes in farming practices and farmland structure)