Source Areas as a Key Factor Contributing to the Recovery Time of Controlled Feral Pigeon (Columba livia var. domestica) Colonies in Low-Density Urban Locations

SIMPLE SUMMARY: Today, governments and administrations strive to minimise issues associated with Feral Pigeon (Columba livia var. domestica) colonies in urban areas, primarily in large city centres. Scientific evidence has demonstrated that control measures are ineffective in the long term, and colonies recover rapidly. Moreover, very few studies have been conducted in residential zones where colony densities are lower, but where Feral Pigeons generate the same issues. Our primary objective was to evaluate the contributions of the following factors to the recovery time of the Feral Pigeon colonies in residential zones: (1) the distance to the closest area where a separate colony of Feral Pigeons was present, i.e., a source area, and (2) the total or partial removal of the previously existing colony. The distance to the nearest uncontrolled colony of Feral Pigeons was the primary factor that contributed to the recovery time, which significantly increased with increasing distance to the source colonies. Our results highlight the relevance of identifying an effective management unit for the implementation of control programmes to reduce immigration rates and increase long-term effects. ABSTRACT: Today, governments and administrations strive to minimise issues associated with Feral Pigeon (Columba livia var. domestica) colonies in urban areas. Scientific evidence has demonstrated that control measures are ineffective in the long term, and colonies recover rapidly. Most scientific research has occurred under high-density circumstances, primarily in large city centres. Moreover, very few studies have been conducted in residential zones or suburban areas where colony densities are lower, but where Feral Pigeons generate the same issues. In this study, we analysed the recovery time of Feral Pigeon colonies in 11 buildings in low-density urban areas where control campaigns were previously conducted to reduce their abundance. Recovery times were highly variable among the buildings (50–3072 days). Distance to the nearest uncontrolled colony of Feral Pigeons, i.e., a source area, was the primary factor that contributed to recovery time, which significantly increased with increasing distance to source colonies. Thus, buildings closest to the Pigeons’ source areas (<500 m) were recolonised more rapidly than were buildings that were >500 m away from source areas. Our findings highlight the relevance of identifying an effective management unit for the implementation of control programmes to reduce immigration rates and increase long-term effects.