On the status of forest birds in tropical and subtropical South America

Abstract

In my 40-year study of South American birds, an important focus has always been species preservation. For this reason, when I wrote the paper about the problem that apparently affects forest birds in South America (Nores 2009), I hoped that some researcher would show me that the problem is, at least, not so important as to have a significant impact on bird conservation. So, when I saw a group of 13 researchers from different countries (despite several of them not having experience in tropical forest birds) claim that there is no evidence for widespread bird decline in protected South American forests (Stouffer et al. 2011); I saw this as a positive contribution. However, after reading the commentary, I am afraid that their arguments are insufficient to show that the problem may not be a threat to bird survival. To start with, I mentioned in my paper that the main problem is in western Amazonia (western Ecuador, western Peru, western Bolivia, western Colombia), the lower eastern slopes of the Andes and the Pacific rainforest, while mountain forests and forests that are outside this area seem to be less affected or unaffected. However, none of the sites included in Stouffer et al. are found in this area. Consequently, their sites are not comparable to mine. As I mentioned in my paper, I too observed a good number of species and individuals in a forest site in Cano Colorado (northeastern Venezuela) and in the Yungas of Cochabamba (Bolivia) at about 800 m. I also found a relatively high species richness at Alexander Von Humboldt National Reserve (eastern Peru), Amacayacu National Park (eastern Colombia) and in some sites of Brazil (Ducke Reserve, Tapajoz Forest Reserve, etc.), although bird activity and abundance was in general low. In relation to that, Hennessey and Rubey (2010) in their web page “Where to watch birds in Bolivia” point out that, due to habitat loss or geographic position, the Hill Tropical (900–500 m) and Lower Tropical (500 m and below) habitats around Villa Tunari, Bolivia (an area where I made a one-day census in 2007) (Table 1), are not as rich in terms of bird life. They added “If your trip also includes visiting lowland habitats in another area of Bolivia, spend most of your time above 1000 m”, which evidences that they also experienced the same problem that I found. Climatic Change (2011) 108:387–390 DOI 10.1007/s10584-011-0163-0