An experimental study on the effectiveness of a gel repellent on feral pigeons

The presence of feral pigeons (Columba livia) in anthropic environments often has a negative impact on human activities, public health, and historic buildings. A number of different kinds of dissuading devices, including gel repellents, are on the market. However, their efficacy has been rarely rigorously tested. We reported the effect of a recent multi-cue gel formulation (Bird Free (R)) on free-living feral pigeons. In order to assess the efficacy of this product in discouraging the birds from occupying buildings, we conducted tests on both a night and a day roost. In addition, we performed a test on sites potentially suitable for nesting, in order to assess how pigeons reacted to the installation of the product just on the small area that can be occupied by a single nest. The tested product totally abolished the presence of feral pigeons at the night roost, and significantly reduced their presence on the day roost area for at least 1 year, compared with the control treatment. In addition, we observed that pigeons are discouraged from building their nests on sites treated with Bird Free (R) for at least 3 months. Our results indicate that Bird Free (R) is an effective method for reducing the location-specific impact of pigeons on buildings. The local effect of the product, strictly limited to the treated area, makes Bird Free (R) not suitable for large-scale pigeon management programs aimed at reducing the carrying capacity of urban environment by lowering nest and roost sites availability.