Abstract
Even though the caatinga has been identified as an important area of endemism for South American birds, few studies have been conducted on the distribution, evolution and ecology of birds in this biome. Understanding how habitats contribute to maintain the regional bird diversity is extremely important. In this study, carried out in the backwoods of the state of Alagoas, we present a rapid survey of a caatinga area and discuss the composition of the avifauna in different habitats. From the record of 105 species, we estimated a local richness of 120 (± 5) species. Among the areas surveyed, the dense caatinga shrub areas contributed with more than 42% of the species, holding most of the forest-dependent birds. The open field areas and the vegetation patches contributed 26 and 24% of the observed richness, respectively. The bird community at the vegetation patches is more similar to that registered in the open caatinga shrub areas, than to the fauna of the open fields where these patches are located. Our results support the need to conserve environments which harbor typical caatinga vegetation, and also vegetation patches with those characteristics in greatly altered environments.
Highlights
The caatinga, with an area of 735,000 km2, covers most of the northeastern Brazilian territory
Even though the caatinga has been identified as an important area of endemism for South American birds (MULLER 1973, CRACRAFT 1985, HAFFER 1985, RIZZINI 1997), the distribution, evolution and ecology of its avifauna have been poorly investigated (SILVA et al 2003)
Coryphospingus pileatus Sicalis luteola the caatinga region, registered in northern Espírito Santo (RIBON 1995); Pseudoseisura cristata (Spix, 1824) – endemic species which has been separated from the old combination Pseudoseisura cristata unirufa, and which occurs in the Pantanal and in Bolivia (ZIMMER & WHITTAKER 2000); Thamnophilus capistratus Lesson, 1840 – recently validated within the T. doliatus (Linnaeus, 1764) complex (ASSIS et al 2007); Compsothraupis loricata (Lichtenstein, 1819); Sporophila albogularis (Spix, 1825) – only two other records are from locations in northern Goiás and Mato Grosso (SILVA 1995); Paroaria dominicana (Linnaeus, 1758) and Agelaioides fringillarius (Spix, 1824)
Summary
We carried out our sampling at the adjacencies of the BR-316 road between the cities of Canapi and Inajá (37°40’21”W and 9°5’55”S), at the borders between the states of Alagoas and Pernambuco, at an area of approximately 63 km (Fig. 1). In order to compare the proportion of each bird species in each of the different environment sampled, we used the Shannon’s diversity index estimate and 95% confidence intervals in each habitat. This estimate technique is based on sampling coverage and includes species which were expected but not sampled (CHAO & SHEN 2003). We compared the avifauna composition among different environments using the Jaccard’s similarity index based on estimates, with abundance data This index was modified from the classical Jaccard index by CHAO et al (2005). The similarity matrix obtained was subjected to ordination analysis using multidimensional scaling (MDS)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
