Avifauna, Alto do Palácio, Serra do Cipó National Park, state of Minas Gerais, southeastern Brazil

: We surveyed the avifauna of Alto do Palácio, Serra do Cipó National Park, Minas Gerais state, Brazil. The park lies in the southern Espinhaço range, a significant biogeographical barrier that separates the forest areas of the Atlantic Forest on its eastern slope and the savanna-like vegetation of the Cerrado to its western slope. Representative habitats include open grasslands, with patches of rocky outcrops and woodlands. We recorded 151 species between 2007 and 2010. Most species occurred in woodlands, with the minority in rocky outcrops, eleven species are of conservation concern, nineteen are endemic to the Atlantic Forest, three to Cerrado, and four to the southeastern Brazilian mountaintops, two of which are restricted to campos rupestres of the Espinhaço range. Our results corroborate that the campos rupestres of the Espinhaço range are not only associated with the Cerrado biome, but harbor species associated with both surrounding biomes (Cerrado and Atlantic Forest) and to the mountaintops of southeastern Brazil, supporting the uniqueness of this vegetation type.


Introduction
The establishment of protected areas is considered one of the most efficient strategies in biodiversity conservation (Ervin 2003). Overall, protected areas capture a substantial component of total biodiversity and help buffer it from potential threats (Bruner et al. 2001;Naughton-Treves et al. 2005). Given the intense dependence of biodiversity conservation on the protected areas strategy and the enormous investments that have been made to establish them, it is important to understand how effectively such areas are achieving this goal (Gaston et al. 2008). Nevertheless, satisfactory syntheses are heavily constrained by the availability and accuracy of existing data. Such is the case for most of the legally protected areas in Brazil, where most national parks lack significant inventories of their flora and fauna (Madeira et al. 2008).
Serra do Cipó National Park (hereafter PNSC), located in Minas Gerais state, in southeastern Brazil, is not an exception to this unfortunate rule (Madeira et al. 2008). The park was originally conceived with the goal of protecting the headwaters of the Rio Cipó, a major tributary of the Rio das Velhas, itself a major part of the large and economically important watershed of the Rio São Francisco. The majestic landscape of numerous waterfalls and clean rivers flowing through rocky mountains also contributed to the decision to legally protect this area.
PNSC lies in the southern Espinhaço range of eastern Brazil, which is a significant biogeographical barrier that divides major hydrological basins and separates two important biomes in its central and southern portions: the forest areas of the Atlantic Forest on its eastern slope, and the savanna-like vegetation of the Cerrado to its western slope (Giulietti et al. 1997). The term "campos rupestres" (rocky fields or rocky grasslands) has been used to describe the vegetation that grows in shallow quartzite soil above 900 m in the Espinhaço range (Giullieti et al. 1997). In the Serra do Cipó, there are notable differences The study area is largely covered by open fields (grasslands) with patches of rocky outcrops that are covered by plant species typical of the campos rupestres habitat. The area also includes numerous watersheds that are bordered by short riparian forests ( Figure 2). Those watersheds form the headwaters of the Rio Preto, an important affluent of the Rio Doce basin.
Serra do Cipó experiences little variation in annual and monthly temperatures (Madeira and Fernandes 1999), but a high degree of daily temperature variation reaching up to 20 o C in winter (Goulart and Rodrigues 2007). Typical conditions at AP are cold and windy at night and hot by midday. Mist is very common throughout the year on the eastern slopes of PNSC (Ribeiro et al. 2009). A climate diagram constructed from temperature and rainfall data collected in situ from February 2005 to December 2008 shows a great degree of variation in rainfall throughout the year. Mean annual rainfall is around 1500 mm but there is a soil water deficit from May to August, which coincides with the coldest months, while there is water in excess from November to March, the warmest months ( Figure 3).

Data Collection
We conducted visual, auditory and mist-netting (12 x·2.5 m, 36 mm mesh) surveys throughout the area from January 2007 to January 2010. Mist-netting efforts included a 2-3 day visits every month over a 24-month period, i.e. 4,450 net-h in total.
We assigned a habitat type (rocky outcrops, open fields or woodlands) to each species based on its occurrence there. Common species were seen during more than 50% of the field trips; uncommon species during less than 50%; and rare species were recorded on three or less individual field trips. To assign their endemic status we followed Stotz et al. (1996) for Atlantic Forest; Silva and Bates (2002), with modifications suggested by Vasconcelos (2008), for Cerrado; for campos rupestres of the Espinhaço range and for eastern Brazilian mountaintops. Regional (Minas Gerais state), national and global conservation status follows Drummond et al. (2008), Silveira and Straube (2008) and BirdLife International (2009), respectively. The taxonomy used here adheres to the checklist of Brazilian birds compiled by the Comitê Brasileiro de Registros Ornitológicos (2009) except for Scytalopus petrophilus, which follows Whitney et al. (2010).

Results and Discussion
A total of 151 species, belonging to 39 families, were recorded (Table 1, Figure 5). Twenty-six species (17%) recorded at AP are endemic to one or other major biome or have an even more restricted geographic distribution. Nineteen are considered endemic to the Atlantic Forest, while Antilophia galeata (Lichtenstein, 1823), Cyanocorax cristatellus (Temminck, 1823), and Poospiza cinerea Bonaparte, 1850 are the only three species considered endemic to the Cerrado region of central South America. Four species recorded at AP, Polystictus superciliaris (Wied, 1831), Embernagra longicauda Strickland, 1844, Augastes scutatus (Temminck, 1824) and Asthenes luizae Vielliard, 1990, are endemic to the mountaintops of southeastern Brazil, with the last two restricted to campos rupestres of the Espinhaço range.
Five species are considered globally Near Threatened, and four are threatened. Culicivora caudacuta is globally, nationally and regionally Vulnerable, Poospiza cinerea and Asthenes luizae are globally Vulnerable, and Scytalopus iraiensis is considered globally and nationally Endangered. Also, two species are considered to be Data Deficient regionally: Sarcoramphus papa (Linnaeus, 1758) and Emberizoides ypiranganus.
Woodland habitats were found to harbor most (90) of the species, with 55 being closely associated to it (i.e. all records were made exclusively in that habitat), while 39 species occurred on rocky outcrops (with three species recorded only in this habitat), and 55 species in open fields with 21 species closely associated to it (Table 1).
Grassland birds are of particular conservation concern as their habitat is being rapidly and irreversibly converted to land for cattle pasture, often by the introduction of exotic grasses. It is estimated that grassland bird populations are declining at an accelerated rate throughout the Americas due to such habitat conversion (Vickery et al. 1999).
The introduction of exotic grasses is a serious threat to vulnerable species like Poospiza cinerea and Culicivora caudacuta (Silveira and Straube 2008;Birdlife International 2009). The latter species is common in the open fields of AP, while the former was only recorded outside of the study area, but very close to the park boundaries, near to the road to Morro do Pilar municipality.
Hummingbirds and tyrant-flycatchers are the most diverse families on rocky outcrops. Hummingbirds are dependent on the flowering booms of the high plant species diversity found in this habitat (see Rapini et al. 2008). Of the three species exclusively recorded in rocky outcrops, Muscipipra vetula (Lichtenstein, 1823) and Pipraeidea melanonota (Vieillot, 1819) were considered to be restricted to forested areas (Stotz et al. 1996), but they have been recently recorded in other areas of campos rupestres (Vasconcelos and Rodrigues 2010). These species were recorded only once, when captured in mist-nets, but probably also occur in other undersampled woodland patches of AP. The other species, Asthenes luizae, is endemic to the Espinhaço Range (Vasconcelos 2008), was recorded in the largest patches of rocky outcrops, at the eastern border of the study area, where Vellozia gigantea N.L. Menezes and Mello-Silva (Velloziaceae), an endemic plant to the Serra do Cipó occurs.
Woodlands are by far the most species-rich habitat at AP due to the fact that this habitat type presents a large spectrum of available niches (August 1983). Woodlands support many species not found in any other habitats, particularly the Atlantic forest endemics. Also, Antilophia galeata, a Cerrado endemic, was only recorded in woodland because this species is restricted to riparian forest (Silva and Bates 2002). It is important to note that woodland birds are more likely to escape detection than those occurring in rocky outcrops and open fields, such that the status of these woodland species should be viewed cautiously. Little is known about the bird community of high-elevation woodland patches in campos rupestres. Our goal here was to present a preliminary species list and assess the bird community of campos rupestres, but more effort concentrated exclusively in this habitat type is necessary to achieve a more complete understanding of its composition and gain some sense of its meta-population dynamics.
The Atlantic Forest is essentially a forested ecosystem that once occurred continuously along the whole east coast of Brazil (Oliveira-Filho and Fontes 2000). The southern Espinhaço range separates the Cerrado and Atlantic Forest biomes, as well as the São Francisco and Rio Doce basins. However the official limit includes the highlands of the Espinhaço range in the Cerrado domain, even those that form the Rio Doce basin, such as AP (Ribeiro et al. 2009). A recent study has shown the presence of typical Atlantic Forest plant taxa, similar climatic conditions, and extensive areas of deforested semi-deciduous habitat on the eastern slope of the southern Espinhaço range, to the extent of proposing new limits for the Atlantic Forest domain (Ribeiro et al. 2009). In fact, since 2000, the eastern slope of the Espinhaço Range in Minas Gerais state has been identified as a priority area for the conservation of mammal and bird species characteristic of the Atlantic Forest (Conservation International et al. 2000).
The ecotonal characteristic of AP is reflected in the presence of birds considered endemic to the Cerrado domain and others typical of open country but associated with the Cerrado (e.g. Rhynchotus rufescens (Temminck, 1815), Nothura maculosa (Temminck, 1815), Cariama cristata (Linnaeus, 1766)) together with birds considered endemic to the Atlantic Forest domain and other typically forest-based species (e.g. Heliomaster squamosus (Temminck, 1823), Phylloscartes ventralis (Temminck, 1824), Poecilotriccus plumbeiceps (Lafresnaye, 1846)). Moreover, in AP we found other species that are more related to highland areas than to one specific biome, including birds endemic to campos rupestres of the Espinhaço range and/or mountaintops of southeastern Brazil. These results corroborate the idea that campos rupestres of the southern Espinhaço Range are not an ecosystem associated with the Cerrado biome only, as it has been viewed by botanists (e.g. Eiten 1992; Ribeiro and Walter 1998;Rapini et al. 2008) and ornithologists (Silva andBates 2002, Machado 2005). Rather, campos rupestres is more accurately viewed as a unique biological unit with an independent evolutionary history (Vasconcelos 2008;Ribeiro et al. 2009).
The AP site is one of the few protected areas on the east slope of the Espinhaço range. This area is rich in preserved natural grassland, riparian forest and relatively large patches of semi-deciduous woodland.
Campos rupestres of the Espinhaço Range act as Holocene refuges. AP harbors populations of species with disjunct distributions from those in southern Brazil (e.g. Scytalopus iraiensis, Cinclodes pabsti, and Emberizoides ypiranganus, and species whose closest relatives occur in the Andes and Patagonia (e.g. Augastes scutatus and Asthenes luizae). Therefore, our records for AP support the biogeographical relationship of the Espinhaço range with particular disjunct regions in South America (Sick 1985;Vielliard 1990;Silveira and Cure 1993;Stehmann and Semir 2001;Vasconcelos et al. 2006;Vasconcelos and Rodrigues 2010).
Our bird surveys in the highlands of PNSC reveal not only an area of high species richness, but also with a distinctive composition. AP includes species associated with the surrounding biome domains and species that are closely associated to the mountaintops of southeastern Brazil, further supporting the uniqueness of this location. By conducting such detailed surveys, we hope to establish a baseline for future studies to assess the importance and effectiveness of this national park in biological conservation efforts.  Table 1. Bird species recorded on ' Alto do Palácio', Serra do Cipó National Park, and its record source, habitat occurrence, abundance, endemic and conservation status. Evidence Type: S = sight, H = heard, A = audio record, P = photography, E = specimens collected, B = blood tissue collected. Habitat: R = rocky outcrops, O = open fields, W = woodlands, A = aerial. Abund. (Abundance status): C = common, U = uncommon, R = rare. End. (Endemism): Af = Atlantic forest, Ce = Cerrado, Cr = campos rupestres of Espinhaço Range, Mt = Eastern Mountain tops. Conserv. (Conservation status): Re, regionally threatened; Na, nationally threatened, Gl, globally threatened (DD, data deficient; NT, Near-Threatened; VU, Vulnerable; EN, Endangered). *occurs only bordering the study area in anthropomorphic areas (cattle pastures and Eucalyptus woodlands).