Avifauna do Parque Estadual da Mata Seca

Abstract

This study aimed to characterize the avifauna of the Mata Seca State Park (MSSP), situated in the district of Manga, north of Minas Gerais state, Brazil. The tropical dry forests constitute one of the most threatened ecosystems in Brazil, and little is known about them. In the first chapter, we described the species diversity across the following habitats of the park: dry forests, lakes, riparian forests and abandoned pastures. The species were classified according to their guilds, dependence of forest area, sensibility of the species as ace disturbances anthropic, and conservation status at the global level and at the state of Minas Gerais level. For species sampling, we used the list method of Makinnon and Phillip (1993), with the modifications suggested by Herzog et al. (2003). We registered 202 bird species distributed into 51 families. The most abundant family was the Tyrannidae (15%), followed by Furnariidae (6%) and Picidae (5%). The species as the largest frequency indexes were: Columbina squammata (0,301), Coryphospingus pileatus (0,216), Icterus jamacaii (0,216) e Aratinga cactorum (0,203). The most representative guilds were the insectivores, with 45% of the registrations, followed by the omnivores with 24% and granivores and carnivores, with 9% each. The independent species of forest areas represented most with 41%, the semi-dependent ones represented 37% and the not dependent 22%. As the sensibility of the species in relation to the disturbance antrópica the species with low sensibility represented 62,8%, the with average sensibility represented 33,6% and high 3,4%. Seven species are considered as threatened at some level: two species were classified as IN DANGER inside the state of Minas Gerais and globally as VULNERABLE (Xiphocolaptes falcirostris franciscanus and Penelope jacucaca); the species Mycteria americana is considered as VULNERABLE only for the state of Minas Gerai; four species are classified as ALMOST THREATENED globally, but not threatened in Minas Gerais: Hylopezus ochroleucus, Primolius maracana, Knipolegus franciscanus and Arremon franciscanus. The distribution of the species in each physiognomy showed that the dry-forests possess the greatest richness (128 species), followed by abandoned pastures (117), riparian forests (74) and lakes (31). These results show the importance of the dry forests for the preservation of bird diversity at IV the MSSP and at the Cerrado and Caatinga biomes, since many recorded species are endemic and extinction-threatened. In the second chapter, we characterized the species richness, abundance and bird community composition across a dry forest successional gradient (early, intermediate and late stages) in the MSSP. Also, we determined how community composition changes between successional stages due to seasonal changes along one year. For this purpose, we used the point-fixed method (Blondel et al. 1970, Bibby et al. 1992), which consists of establishing observation points inside the sampled areas. Points were 200 m distant from each other and all birds inside a 50 m radius from the point were recorded for 10 min. The initial stage showed the highest bird richness (78 species), followed by intermediate (67) and late (65) stages. Community composition in the early stage was also different from advanced stages in both dry and rainy seasons. Intermediate and late stages had a similar bird composition, species richness and abundance at each season. However, bird communities changed significantly between the dry and rainy seasons for all stages. The displacement of some species between stages across seasons is probably determined by differential resource availability. Plant composition and phenology differs between successional stages, especially between the early and the other two advanced stages, changing the spatial availability of flowers, fruits and seeds. Given the importance of the dry forests for the regional bird diversity and their current high level of disturbance, urgent conservation strategies are needed to preserve forest integrity in the north of Minas Gerais