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Breeding Population of Red-Legged Cormorant (Phalacrocorax gaimardi) along the Araucania Region Coast, South-Central Chile

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Abstract

The Red-legged Cormorant (Phalacrocorax gaimardi) is a neotropical cormorant, with a moderately small population and currently categorized as “Near Threatened”. The Red-legged Cormorant is distributed only in the coasts of Perú, Argentina and Chile; however, just a small area in Chile constitutes an important breeding population for this species. Between 1998 and 2000 the entire breeding population size of Red-legged Cormorant and its distribution in Chile were determined, but some areas were poorly surveyed. The breeding population sizes of Red-legged Cormorant were surveyed along the Araucania coast, an area of south-central Chile not considered in previous studies. A total of 3,175 nests and 13,018 adults were distributed over 10 breeding colonies. Our results modified the entire breeding population size of Red-legged Cormorant known for Chile by almost 62% (from 5,018–5,218 to 8,193–8,393 breeding pairs) and by almost 43.4% the world estimates population (from 30,000 to 43,018 individuals). This area could be one of the most important breeding areas for this species in the world. Currently, the colonies of Piureo-Puaucho (1,506 nests), Nigue (1,009 nests) and Punta Ronca-Queule (964 nests), represent almost 42% of the breeding population of this species in Chile, so these breeding sites should be a priority for conservation efforts.
... In Chile, surveys during 1998-2000 produced an estimate of 5,018-5,218 breeding pairs distributed along 40 breeding sites (Frere et al. 2004). Then, during 2010-2012, 10 unsurveyed sites were described and the known population increased to 8,393 breeding pairs (Barros et al. 2014). Although El Niño Southern Oscillation (ENSO) events may have led to distributional changes (with southern regions having become particularly important for the species), the population declines reported in Peru do not seem to have been mirrored in Chile (Frere et al. 2004) where the population trend is unknown, but is presumed to be stable. ...
... More recently, the population appears to be recovering and the overall decline from 1990 to 2009 was 11%, with an estimated annual reduction of about 1.2% per year (Millones et al. 2015). The world population has been estimated at 40,000 individuals (Barros et al. 2014). ...
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