Bol. Mus. Para. Emílio Goeldi. Cienc. Nat., Belém, v. 6, n. 2, p. 147-161, maio-ago. 2011 Avifaunal inventory of a Southern Amazonian transitional forest site: the São Luiz farm, Mato Grosso, Brazil Inventário da avifauna de uma área em floresta de transição no sul da Amazônia: Fazenda São Luiz, Mato Grosso, Brasil Luiz Augusto Macedo MestreI, II, Juliana RecheteloII, III, Mark Alan CochraneI, Jos BarlowIV I South Dakota State University. Brookings, South Dakota, U.S.A. II Universidade Federal do Paraná. Palotina, Paraná, Brasil III James Cook University. Townsville, Queensland, Austrália IVLancaster University. Lancaster, Lancashire, Inglaterra Abstract: This paper describes the avifauna sampled at the São Luiz farm, in Northern Mato Grosso State, a Southern Brazilian Amazonian forest site. The avifauna was sampled at forested and open sites, between 29 June and 27 July 2008, using point counts, mist-nets and general observations. We recorded 194 bird species within 18 orders and 46 families. The records of this study expanded the known range limits of at least 16 bird species. Despite the need for sampling in other seasons, the rarefaction curves indicate a representative sampling effort. The bird community observed at this site contains most of the species typically associated with Amazonian forests, south of the Amazon, and suggests that ‘transitional forests’ found at this site should be qualified as ‘Amazonian’ when considering their legal status. Our data highlights the importance of this anthropogenically-impacted and poorly-known region of Amazonia. Keywords: Bird checklist. Amazonian Birds. Northern Mato Grosso. Southern Amazon. Resumo: Este estudo descreve a avifauna amostrada na fazenda São Luiz, norte do estado do Mato Grosso, uma área de floresta localizada no sul da Amazônia brasileira. A avifauna foi amostrada em florestas e áreas abertas, utilizando os métodos de pontos de contagem, redes-neblina e observações gerais. Registramos 194 espécies de aves, incluídas em 18 ordens e 46 famílias. Os registros deste estudo expandiram a área de ocorrência de ao menos 16 espécies de aves. Apesar da necessidade de amostrar outras estações, as curvas cumulativas de espécies indicaram um esforço amostral representativo. A avifauna observada nesta área contém a maioria das espécies tipicamente associadas com florestas da Amazônia meridional, sugerindo que florestas de ‘transição’ dessa localidade devam ser qualificadas como ‘amazônicas’ no que se refere ao seu status legal. Nossos resultados atestam a relevância dessa região impactada e ainda pouco conhecida da Amazônia. Palavras-chave: Lista de espécies de aves. Aves amazônicas. Norte do Mato Grosso. Sul da Amazônia. MESTRE, L. A. M, J. RECHETELO, M. A. COCHRANE & J. BARLOW, 2011. Avifaunal inventory of a Southern Amazonian transitional forest site: the São Luiz farm, Mato Grosso, Brazil. Boletim do Museu Paraense Emílio Goeldi. Ciências Naturais 6(2): 147-161. Autor para correspondência: Luiz Augusto Macedo Mestre. Universidade Federal do Paraná. Rua Pioneiro, 2153 – Jardim Dallas. Palotina, PR, Brasil. CEP 83255-000 ([email protected]). Recebido em 02/02/2010 Aprovado em 20/07/2011 Responsabilidade editorial: Alexandre Aleixo 147 Avifaunal inventory of a Southern Amazonian transitional forest site INTRODUCTION been recognized as being the key to improving knowledge Over the last thirty years, increasing populations and its about Amazonian biodiversity (Capobianco et al., 2001). development pressures have lead to extensive deforestation Herein, we report the ornithological results of a bird survey of Amazonian forests (Nepstad et al., 1999; Skole & Tucker, at the São Luiz farm, emphasizing that these sites are some 1993; Skole et al., 1994). Forest degradation became of the last patches of ‘terra firme’ forests located in southern widespread in the Amazon with the boom of logging activity Mato Grosso State, Brazil. in the mid 1980’s and in the following decades (Nepstad et al., 1999; Laurance et al., 2001; Carvalho et al., 2002). About METHODS 20% of the Brazilian Amazon has been deforested during This study was conducted at the São Luiz farm, located 30 years of occupation (INPE, 2010). The borders of the close to the MT 110 State Road in the municipality of biome have been the most affected, including the Brazilian Querência in Mato Grosso State, Brazil. The site is placed States of Mato Grosso, and Pará, which together comprise on the east bank of the Tanguro river (an affluent of the more than 60% of the deforested territory (INPE, 2010). Xingu river), to about 25 km from the Xingu National Park Most Amazonian forests in Mato Grosso have already being (S 12° 38’ 40”, W 52° 23’ 5”; S 12° 41’ 15”, W 52° 21’ 38”). changed by logging and clear-cutting, then converted to The farm covers an area of 1,300 ha, including 650 ha of large-scale plantations and cattle ranching fields. In contrast fragmented transitional Amazonian forest. Only one river to this extensive land exploitation, forests in Mato Grosso (the Semp River) passes through the region. The cultivated and neighboring areas have been poorly studied in terms of areas are primarily comprised of soybean and corn, with their biodiversity (i.e. Zimmer et al., 1997; Lees et al., 2008; Brachiaria sp. grass pastures for cattle in some open sites. Aleixo & Poletto, 2007; Whittaker, 2009). The avifauna was sampled at forested and open sites Most published ornithological inventories for Mato (S 12° 38’ 44.14”, W 52° 23’ 4.50”; S 12° 41’ 15.76”, W Grosso State (and neighboring areas) include the habitats 52° 21’ 38.07”), between 29 June and 27 July 2008. We of ‘cerrado’ and ‘pantanal’ (Naumburg, 1930; Stone & recorded birds in forested sites using mist-nets, point counts, Roberts, 1934; Pinto, 1940; Pinto & Camargo, 1948; Silva and general observations methods, whereas those in open & Oniki, 1988; Willis & Oniki, 1990; Dubs, 1992; Silveira & areas were recorded only through general observations. d’Horta, 2002). Only six bird checklists describing typical or General observations were performed not just along the transitional upland Amazonian forests (‘terra firme’) in Mato forest trails, but included main roads and plantations. Grosso have been published to date (Fry, 1970; Novaes, Our sampling units consisted of twelve 550 m long 1976; Novaes & Lima, 1991; Zimmer et al., 1997; Lees et transects, each with four points separated by 150 m from al., 2008; Aleixo et al., 2010). The published data shows each other (i.e., 50 m, 200 m, 350 m, and 500 m). At that most of the birds living in ‘terra firme’ forests in Mato each of these 12 transects, 28 mist-nets (12 x 2.5 m; mesh Grosso come from the Xingu bird endemism area (Borges, size 36 mm) were distributed in four groups of seven 2007). Some sites in this state can be home to about 350 nets at each point. Mist-nets were opened for two days, species with the southern transitional areas poorer than from sunrise (6:30 h) to 13:30 h, yielding a total sampling northern sites (i.e. 362 sp.: Lees et al., 2008; 238 sp.: effort of 4,700 mist-net-hours. We checked the nets Aleixo et al., 2010). The region has many endemic bird hourly and closed them during periods of heavy rain. All species, and the relative abundance of more common birds captured were identified to species level, weighed, species may be very different from those observed in other measured (standard measurements included wing, tail, Amazonian areas. Surveys of community composition have bill, and total length) and, whenever possible, aged, sexed 148 Bol. Mus. Para. Emílio Goeldi. Cienc. Nat., Belém, v. 6, n. 2, p. 147-161, maio-ago. 2011 and photographed. Captured birds were banded with flying the point counts were excluded from the analysis. numbered metal bands obtained from Centro Nacional de Estimates of the ‘true’ species richness in each habitat Pesquisa para Conservação de Aves Silvestres (CEMAVE) – were also calculated using EstimateS v.7, using the mean Instituto Chico Mendes de Conservação da Biodiversidade of the four commonly employed abundance-based (ICMBio). All recaptures from the same sampling period estimators (ACE, CHAO1, JACK1 and BOOTSTRAP). (two days) and from the same net line were excluded from Avian guild classification was based on Terborgh et al. the analysis to avoid double counting. (1990), and species sensitivity and number of habitats In addition to mist-netting, Luiz Mestre carried used by each species were taken from Stotz et al. (1996). out 96 point counts along the same 12 transects and We followed the CBRO (2009) list for nomenclature and points also sampled with mist-nets. Any given point taxon ordinance. was sampled twice on different days, but not on the same days as mist-netting. Point counts were conducted RESULTS AND DISCUSSION between 6:30 h and 9:00 h and lasted ten minutes each. We registered 194 bird species from 18 orders and 46 families, Most birds recorded during point counts were registered occurring at the São Luiz farm, between 29 June and 27 July with a Marantz PMD 671 digital recorder coupled to a 2008. The most representative families were Tyrannidae, Sennheiser MKH 60 directional microphone. Whenever Thraupidae, and Thamnophilidae with 28, 16 and 15 species possible, identifications of birds recorded during point respectively. Mist-nets captured 455 individuals of 74 species counts were confirmed visually with the aid of binoculars. belonging to 22 families, and point counts recorded 1,880 Unknown vocalizations were subsequently checked individuals of 144 species belonging to 34 families. against known calls and songs and, if necessary, confirmed Of the species captured in mist-nets, 94% were by consulting other experienced ornithologists (i.e., A. Passeriformes, including Pipridae (32.5% of individuals), Aleixo and S. Dantas). For each record obtained at point Tyrannidae (16.9%), Thamnophilidae (16%), and counts, the distance from the observer and the height Dendrocolaptidae (12.6%).