Changes in the breeding habits and season of the Cave Swallow (Petrochelidon fulva) in Puerto Rico

The common name of the Cave Swallow (Petrochelidon fulva) originated from its behavior to nest at the entrance of caves and sinkholes where it constructs mud nests. The bird is one of the two species of swallows that breeds in Puerto Rico. The usual habitat of these swallows used to be coastal habitats such as mangroves and open fields but they have colonized urban habitats such as balconies, cement bridges and other human made structures. It seems that a change has taken place in the breeding season of the Cave Swallow. The changes in the breeding season have been documented in both colonies, the colonies living in urban settlements and the colonies nesting at the entrance of caves. The onset of the breeding season of the Cave Swallow, at least in urban habitats, is triggered by rain. The causes of the change in the breeding season seems to be associated to changes in temperature and on the raining patterns which in turns seems to affect the abundance of prey consumed by the swallows. Professor Pérez suggests that the Cave Swallow could be used as a good predictor of climatic change. Keywords: Cave Swallow, Petrochelidon fulva, change in breeding season, climatic change.