Natural history of the Peruvian Booby (Sula variegata) in the Quirilluca cliffs, Valparaíso, Chile

Abstract

The Peruvian Booby (Sula variegata) is a seabird considered threatened in Chile. This species nests in the Quirilluca cliffs, which is the only continental breeding area in central Chile. We studied this population in order to establish abundance and spatial distribution of the colony, to determine the breeding period and to identify current threats in the area. Twelve censuses were carried out between September 2013 and May 2015. The largest number of adults was recorded between December and February, with a maximum of 4638 birds. Breeding is not synchronic and covers a long period, from September until April. Main threats are focused on eggs and nestlings, and both natural (aerial and terrestrial predators, nestlings that fall off the cliffs) and human related causes (visitors, gathering of eggs for local consumption, paragliders soaring the colony) can be distinguished.