Urban pigeon populations: stability, home range, and the effect of removing individuals

Abstract

The population stability and home ranges of rock doves (Columba livia var.) were investigated by means of surveys and monitoring of marked individuals. We also studied the population response to removal of animals. Pigeons used small home ranges, and there was very little exchange between adjacent populations despite their proximity. Individual day attendance at the home range was not bimodal, so individuals cannot be divided into regular and sporadic visitors. The number of individuals remained very stable during the 5 months of the study. Pigeons did not show any group cohesion, but individuals simply used the same small area. The consequence of the removal experiments was a rapid immigration of individuals from areas where no control was exerted, supporting the hypothesis that compensatory changes in dispersal are probably the main mechanism of pigeons' response to external perturbations. The rapid response after control and the disappearance of marked pigeons over time indicate the existence of some sampling movements of individuals between alternative sites. Redistribution of pigeons after the creation of a population vacuum would be in accordance with current models of habitat selection.