Seasonal Distribution and Range of the
Transcrição
Seasonal Distribution and Range of the
Seasonal Distribution and Range of the Blackish-Blue Seedeater (Amaurospiza moesta): A Bamboo-Associated Bird Author(s) :Leonardo Esteves Lopes, João Batista De Pinho, and Carlos Eduardo R.T. Benfica Source: The Wilson Journal of Ornithology, 123(4):797-802. 2011. Published By: The Wilson Ornithological Society DOI: URL: http://www.bioone.org/doi/full/10.1676/10-153.1 BioOne (www.bioone.org) is a a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/ terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. The Wilson Journal of Ornithology 123(4):797–802, 2011 SEASONAL DISTRIBUTION AND RANGE OF THE BLACKISH-BLUE SEEDEATER (AMAUROSPIZA MOESTA): A BAMBOO-ASSOCIATED BIRD LEONARDO ESTEVES LOPES,1,4 JOÃO BATISTA DE PINHO,2 AND CARLOS EDUARDO R. T. BENFICA3 ABSTRACT.—Avian bamboo specialists are an ecologically distinctive group of birds in the Neotropics with some seedeater species having nomadic movements following bamboo (Guadua, Chusquea or Rhipidocladum) mast seeding. We reviewed the range and seasonal distribution of Blackish-blue Seedeaters (Amaurospiza moesta) using published and unpublished records, museum specimens, sound libraries, and intensive field work. We report the first occurrence of Blackish-blue Seedeaters in the Brazilian State of Mato Grosso, a male collected in Fazenda Baı́a de Pedra, Cáceres (16u 279 290 S, 58u 099 590 W). We also recorded this species in two localities in the Cerrado region (a tropical savannah) of Minas Gerais: the Santo Antonio River, Presidente Olegário (18u 079 480 S, 46u 119 570 W), and the Abaeté River, São Gonçalo do Abaeté (18u 059 S, 45u 229 W). These records represent a remarkable range extension, demonstrating this species is distributed across the Cerrado. We found no evidence of regular large scale or local movements of this species, which seems to be resident, at least in Argentina, which had the largest data set. Received 15 September 2010. Accepted 4 April 2011. Amaurospiza is a small and homogeneous neotropical genus of mid-size finches generally associated with bamboo (Guadua, Chusquea or Rhipidocladum) thickets and dense forest undergrowth (Ridgely and Tudor 1989, Stotz et al. 1996, Lentino and Restall 2003). Avian bamboo specialists generally have two distinct life-history strategies. The first is exhibited by insectivorous resident species that inhabit forests dominated by bamboo, where they find shelter, nest sites, and food (Parker et al. 1997, Areta et al. 2009). The second is specialization on bamboo seeds, which is a rarer strategy, because these specialists must rely on an ephemeral source of food (Areta et al. 2009). This is because most woody bamboo species are semelparous (individuals have only a single period of reproduction in their lives, after which they die) with simultaneous flowering and subsequent death of entire populations that, in certain American bamboos, occur in cycles of 30– 40 years (Janzen 1976, Judziewicz et al. 1999, Bystriakova et al. 2004). Bamboo seed specialists, therefore, wander to survive, and nomadic move1 Laboratório de Zoologia, Ciências Biológicas, Universidade Federal de Viçosa, Campus Florestal, Rodovia LMG-818, km 6, 35690-000, Florestal, Minas Gerais, Brazil. 2 Núcleo de Estudos Ecológicos do Pantanal, IB, Universidade Federal de Mato Grosso, Av. Fernando Corrêa, 78075-960, Cuiabá, Mato Grosso, Brazil. 3 SOS Falconiformes, Rua Odilon Braga 1370, 30310390, Belo Horizonte, Minas Gerais, Brazil. 4 Corresponding author; e-mail: [email protected] ments make these species particularly difficult to study (Areta et al. 2009). Nomadic movements differ markedly from regular migration, which is predictable and seasonal. Nomadic movements are irregular, and destinations may differ from year to year, revealing an adaptation to use of resources that are patchy in space and time (Sinclair 1984). The most widely distributed Amaurospiza species is the near-threatened Blackish-blue Seedeater (A. moesta) (Birdlife International 2010). Habitat requirements and movements of this species are poorly known, making it a high conservation and research priority (Stotz et al. 1996). The range of Blackish-blue Seedeaters is still imperfectly known, and it is erroneously considered endemic to the Atlantic Forest (Stotz et al. 1996), a tropical forest mainly distributed across eastern Brazil, considered as a hotspot of biodiversity (Myers et al. 2000). An isolated occurrence of Blackish-blue Seedeaters in the Cerrado is known since Snethlage (1928) who collected a single male in the southern Brazilian State of Maranhão (Hellmayr 1929). The Cerrado is a tropical savannah mainly distributed across central Brazil, also acknowledged as a hotspot of biodiversity (Myers et al. 2000). This ‘extralimital’ occurrence, 800 km from the Atlantic Forest border, and 1,400 km from the nearest known occurrence at that time, was recently corroborated by observations in the northern border of the Cerrado (Pacheco et al. 2007). Seasonal distribution of this species has not 797 798 THE WILSON JOURNAL OF ORNITHOLOGY N Vol. 123, No. 4, December 2011 been investigated in detail, and it has been suggested that all Amaurospiza are nomadic to some extent (Lentino and Restall 2003). The Blackish-blue Seedeater feeds mainly on seeds, but it does not appear to be an obligatory specialist on bamboo seeds (Areta et al. 2009); consequently, it may not need to wander to survive. Records of this species in extreme southern Brazil are concentrated in some months of the year (Belton 1994) and the possibility that it performs regular seasonal migration has not been investigated. We reviewed the range of the Blackish-blue Seedeater and present noteworthy range extensions. We studied its seasonal distribution, looking for evidence of regular large scale movements in latitude, longitude, or elevation. The possibility of nomadic movements by this species was also briefly considered. METHODS Several sources of data were used to identify the range of Blackish-blue Seedeaters. We (1) compiled our unpublished field records and those obtained by several experienced observers; (2) performed a wide literature review; (3) visited nine Brazilian and three North American museums; (4) wrote to curators of another four Brazilian and five European museums; (5) checked the on-line data bases of many other museums, and (6) checked for tape recordings in three sound libraries. Geographical coordinates were obtained from ornithological gazetteers (Paynter 1989, 1995; Paynter and Traylor 1991). We also benefited from a wide review by L. P. Gonzaga when he sketched an account of this species for the American birds Red Data Book (Collar et al. 1992), which was later not included. We examined the seasonal distribution of this species from three bivariate plots with the month along the x-axis and latitude, longitude, and elevation along the y-axis. Seasonal concentration of records in some areas of the plot should provide evidence for regular long-distance or altitudinal migration. Small scale or nomadic movements are more difficult to study, requiring long-term bird monitoring programs, which are lacking for Blackishblue Seedeaters. Evidence of local fluctuations in abundance of this species can be obtained by examining the monthly variation in number of collected specimens in the Province of Misiones, Argentina, which has the largest series of this species. We are aware these data are sensitive to bias in collecting effort. We circumvented this problem by making comparisons between the number of Blackish-blue Seedeaters and Bufffronted Foliage-gleaners (Philydor rufum) collected throughout the year. This latter is a forest species (Remsen 2003) that also inhabits areas with extensive growth of bamboo (Rodrigues et al. 1994). We used Spearman Rank Order Correlation (Sokal and Rohlf 1995) to investigate if numbers of collected specimens of both species were correlated. A strong correlation should suggest that monthly variation in the abundance of Blackish-blue Seedeaters is attributable to collecting effort and that, consequently, it is a resident species, as is the Buff-fronted Foliagegleaner. RESULTS AND DISCUSSION Blackish-blue Seedeaters range from southeastern Brazil (eastern Minas Gerais and Rio de Janeiro southward) to southeastern Paraguay and northeastern Argentina in the Atlantic Forest (Fig. 1; a complete list of the occurrences of this species, including unacceptable records is available upon request from the senior author). It also occurs in the Cerrado region in the states of Maranhão (Hellmayr 1929), Tocantins (Pacheco et al. 2007), and Mato Grosso do Sul (Silva 1995b). We present the first records for the Cerrado from Minas Gerais and the first state record for Mato Grosso. The first Minas Gerais record was obtained in the Santo Antônio River (18u 079 480 S, 46u 119 570 W, 680 m asl), municipality of Presidente Olegário. A single male was observed singing on 2 March 2009 and a female was mist-netted the following day. Both individuals were photographed. Local vegetation was a second growth riparian forest (4–9 m tall) with dense understory dominated by an unidentified bamboo species bearing seeds. A second record was obtained on 22 October 2010 by Eduardo Gazzinelli (pers. comm.) on the Abaeté River (18u 059 S, 45u 229 W, 635 m asl), municipality of São Gonçalo do Abaeté (tape-record deposited in XC 67339; acronyms in Table 1). These localities are ,90 km apart. The Mato Grosso record was obtained on 24 February 2008, when we tape-recorded (ASEC 16382 and XC 21052) the typical song of this species in the Fazenda Baı́a de Pedra (16u 279 290 S, 58u 099 590 W, 110 m asl), municipality of Cáceres (Fig. 1). This area is in the northern Lopes et al. N DISTRIBUTION OF BLACKISH-BLUE SEEDEATER 799 FIG. 1. The range of the Blackish-blue Seedeater (Amaurospiza moesta). Black dots indicate occurrences in the Atlantic Forest and white boxes with dots indicate occurrences in the Cerrado: 1 5 Tranqueira (Hellmayr 1929), 2 5 Fazenda Harmonia (Silva 1995b), 3 5 Lizarda, 4 5 Santa Maria do Tocantins, 5 5 Miracema do Tocantins (Pacheco et al. 2007), 6 5 Fazenda Baı́a de Pedra (this study), 7 5 Santo Antonio River (this study), and 8 5 Abaeté River (this study). Gray tones indicate the main vegetation types (Olson et al. 2001). border of Brazilian Pantanal, the world largest floodplain (Silva et al. 2001). The tape-recorded bird was collected and deposited in the collection of DZUFMG (# 5771). This specimen weighed 14.5 g, and had an ossified skull, enlarged testes (9 3 6 mm), and light fat indicating breeding condition and likely breeding activities in the area. The collection site was formerly an unflooded tall semideciduous to deciduous forest, logged about 40 years ago and converted into 800 THE WILSON JOURNAL OF ORNITHOLOGY N Vol. 123, No. 4, December 2011 TABLE 1. Acronyms of institutions visited or consulted and location. Acronym AMNH ASEC CM COMB DZUFMG FMNH IAL LACM LSUMZ MACN MBML MCN-FZB MCN-PUCRS MHNCI ML MNRJ MPEG MZJH MZJMO MZUSP NHM NMW NRM RECOR UFMT UFPE UMMZ USNM XC ZFMK ZMB Institution Location American Museum of Natural History Arquivo Sonoro Elias Coelho Carnegie Museum of Natural History Coleção Ornitológica Marcelo Bagno, Universidade de Brası́lia Departamento de Zoologia, Universidade Federal de Minas Gerais Field Museum of Natural History Coleção Zoológica de Referência do Instituto Adolfo Lutz Los Angeles County Museum of Natural History Louisiana State University Museum of Natural Science Museo Argentino de Ciencias Naturales Bernardino Rivadavia Museu de Biologia Professor Mello Leitão Museu de Ciências Naturais da Fundação Zoobotânica do Rio Grande do Sul Museu de Ciências Naturais, Pontifı́cia Universidade Católica do Rio Grande do Sul Museu de História Natural Capão do Imbuia Macaulay Library of Sounds Museu Nacional Museu Paraense Emı́lio Goeldi Museu de Zoologia José Hidasi Museu de Zoologia João Moojen de Oliveira, Universidade Federal de Viçosa Museu de Zoologia da Universidade de São Paulo Natural History Museum Naturhistorisches Museum Naturhistoriska Riksmuseet Reserva Ecológica do Instituto Brasileiro de Geografia e Estatı́stica Universidade Federal de Mato Grosso Universidade Federal de Pernambuco University of Michigan Museum of Zoology National Museum of Natural History Xeno-Canto Foundation Forschungsmuseum Alexander Koenig Museum für Naturkunde pastures and rice plantations (Luciano Arruda, pers. comm.). The area was abandoned ,25 years ago, and is now covered by a dense stand of 3-m tall Guadua bamboo, a common invasive species in the region. This same bamboo stand produced fruits in 2007, accordingly to local owners, but we did not observe seeds when we visited the area. The range of Blackish-blue Seedeaters is puzzling with scattered occurrences in regions subject to several different climatic regimes, elevation, and vegetation types. This species appears to be absent or rare in extensive areas of apparently suitable habitat in southeastern Brazil. The patchy distribution of Blackish-blue Seedeaters across the Cerrado may also be due to sampling effort, because ,70% of it has not been satisfactorily sampled for birds (Silva 1995a). Particularly poorly sampled is the central-north New York, NY, USA Rio de Janeiro, RJ, Brazil Pittsburgh, PA, USA Brası́lia, DF, Brazil Belo Horizonte, MG, Brazil Chicago, IL, USA São Paulo, SP, Brazil Los Angeles, CA, USA Baton Rouge, LA, USA Buenos Aires, MIS, Argentina Santa Teresa, ES, Brazil Porto Alegre, RS, Brazil Porto Alegre, RS, Brazil Curitiba, PR, Brazil Ithaca, NY, USA Rio de Janeiro, RJ, Brazil Belém, PA, Brazil Porto Nacional, TO, Brazil Viçosa, MG, Brazil São Paulo, SP, Brazil Tring, United Kingdom Wien, Austria Stockholm, Sweden Brası́lia, DF, Brazil Cuiabá, MT, Brazil Recife, PE, Brazil Ann Arbor, MI, USA Washington, D.C., USA Amsterdam, The Netherlands Bonn, Germany Berlin, Germany and western portion, where extensive areas dominated by Guadua woody bamboos occur (Bystriakova et al. 2004: map 3.4). These regions are poorly sampled as demonstrated by several first reports of Kaempfer’s Woodpecker (Celeus obrieni), a bamboo specialist, until quite recently known only from its type specimen collected in 1926 (Dornas et al. 2011). The Blackish-blue Seedeater seems to be common in its limited range in Argentina (Chebez 2009). William Partridge collected more than 140 Blackish-blue Seedeaters in Misiones in the 1950s (Partridge 1953, 1954). In contrast we located ,50 skins of this specimen from throughout its range outside Misiones. We found no evidence of regular large scale movements in latitude, longitude or elevation by this species, as demonstrated by three bivariate Lopes et al. N DISTRIBUTION OF BLACKISH-BLUE SEEDEATER plots, which revealed no seasonal concentration of records in some areas of the plot. We found no evidence of regular movements between the Atlantic Forest and the Cerrado. Records of Blackish-blue Seedeaters in the Cerrado are from January, February, March, April, July, August, September, and October (Hellmayr 1929, Silva 1995b, Pacheco et al. 2007, this study). Blackish-blue Seedeaters have been recorded throughout the year in Misiones. There are, for example, specimens collected in every month of the year in Arroyo Uruguay-ı́, a well sampled locality. Differences in number of collected specimens in Misiones through the year are probably attributable to collecting efforts, as demonstrated by the positive correlation between numbers of collected specimens of Buff-fronted Foliage-gleaners and Blackish-blue Seedeaters (Spearman Rank Order Correlation; n 5 12, R 5 0.63, P 5 0.03). Data available for Brazil are scarce, and does not allow a similar analysis. However, in the State of Paraná, which provides the majority of Brazilian records, there are records for all months of the year, except December. We cannot reject the hypothesis of nomadic movements with the data available, but we found no evidence of regular large scale or local movements, suggesting this species is a year-round resident, at least in Argentina. ACKNOWLEDGMENTS LEL benefited from a doctoral fellowship from FAPEMIG during part of this study. Our field work was supported by grants from Núcleo de Estudos Ecológicos do Pantanal, Centro de Pesquisa do Pantanal, Instituto Nacional de Áreas Úmidas, and Ministério da Ciência e Tecnologia. Visits to North American museums were made possible through a Collection Study Grant received by LEL from AMNH. Luciano Arruda allowed our study in Cáceres and provided logistic support. Pedro Viana kindly identified the bamboo species, and Guilherme Freitas compared DZUFMG specimens with others housed in MNRJ. We thank IBAMA for providing a collection permit (14496-1). Eduardo Gazzinelli, Luiz dos Anjos, Luiz Gonzaga, Silvana Luçolli, Gustavo Malacco, Manuel Nores, José Fernando Pacheco, Mark Pearman, Nelson Pérez, Renato Pineschi, Bret Whitney, Andrew Whittaker, and Darı́o Yzurieta shared unpublished field records with us. Curators who provided us with facilities to study their collections were: Miguel Marini (COMB); Marcos Rodrigues (DZUFMG); Hélio Fernandes (MBML); Marcos Raposo and Jorge Nacinovic (MNRJ); Alexandre Aleixo and Fátima Lima (MPEG); Luis Fábio Silveira (MZUSP); Advaldo Prado (MZJH); Renato Feio (MZJMO); Marina Resende (RECOR); Joel Cracraft, Paul Sweet, and Margaret Hart (AMNH); Brad Livezey and Stephen Rogers (CM); and 801 Storrs Olson and Brian Schmidt (USNM). The following curators kindly sent data on specimens housed in their collections: Roberta Rodrigues (UFPE), Pedro Scherer Neto (MHNCI), Carla Fontana (MCN-PUCRS), Glayson Bencke (MCN-FZB), Ernst Bauernfeind (NMW), Göran Frisk (NRM), Sylke Frahnert (ZMB), Karl-Ludwig Schuchmann (ZFMK), and Robert Prys-Jones (NHM). The following museums kindly made available on-line data on specimens housed in their collections at the SpeciesLink (http://splink. cria.org.br/) or at the ORNIS (http://ornisnet.org) portals: LACM, UMMZ, FMNH, and IAL. Luiz Gonzaga sent data on tape recordings deposited in the sound archive under his care (ASEC), as well as a compilation of records of this species. XC (http://www.xeno-canto.org) and ML (http:// macaulaylibrary.org/index.do) kindly made available online their sound archives. C. E. Braun, Peter Vickery, Gary Ritchison, Robin Restall, Juan Areta, Marcelo Vasconcelos, and an anonymous reviewer provided useful comments on previous versions of this manuscript. 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