Associated birds to the Carriel Sur Airport of Talcahuano, south of Chile: evaluation of endangered aviary

Abstract

Between the summer 2002 and 2005 was evaluated the richness and abundance of birds associated to the Carriel Sur Airport of Talcahuano and was estimated the collision risk representing each species for air navigation. Birds were counted in 10 count points distributed in different habitats around the landing runways. The collision risk was estimated by the Avian Hazard Index (AHI) which combines size, abundance and history of collisions of each species. During the study period 63 species were recorded, plus 10 aditional species were recorded after summer 2005. The most abundant species were the Grassland Yellow-Finch, Kelp Gull, Southern Lapwing Long-tailed Meadowlark (28%, 14%, 10%, 8% of all individual records). Excepting Kelp Gull, all remaining species exhibited seasonal cycles of abundance. The Kelp Gull showed multiyear outbreaks triggered. The species representing a higher collision risk for air navigation are the Kelp Gull (API = 36), Southern Lapwing (AHI = 24), South American Tern (AHI = 16), Black Vulture (AHI = 12), Neotropic Cormorant (AHI = 9) and Chimango Caracara (AHI = 8). However, the each species’ AHI varied temporally from very high to very low values according to changes in abundance. This study reflects the need for long-term assessments of changes in population size of bird species to better approximate the risk of bird-aircraft collisions.