Two centuries of ornithological exploration of the Rio Doce basin, southeastern Brazil. Part IA history of the landscape, its explorers, and their collections.

The Rio Doce Hydrographic Basin (RDB) was once covered by magnificent tropical forest, which remained untouched by Europeans for three centuries after the arrival of the Portuguese colonists in the Brazilian coast in 1500. Nevertheless, a dramatic change in land use occurred throughout the entire RDB after the turn of the 19th century. Currently, the RDB is one of the most degraded regions in southeastern Brazil and, recently, it was the scenario of the worst environmental disaster in Brazilian history. In this series of papers, we aim to construct a baseline biodiversity assessment that documents the changes in bird communities within the RDB throughout the last two centuries. In this first part, we present the history of the RDB landscape, its explorers, and their collections based on an extensive literature review and museum data. Early biological surveys in the RDB only started at the beginning of the 19th century and were conducted mostly by German and French naturalists. During the first eight decades of ornithological exploration, foreign field naturalists conducted expeditions to the RDB and collected hundreds of bird specimens. Unfortunately, labelling and curatorial procedures were often poor and despite the prodigious efforts of those naturalists, results obtained were often meagre. The second phase of exploration occurred from the 1900s to the 1960s and was dominated by expeditions conducted by Brazilian natural history museums. During this phase, labelling and curatorial procedures improved considerably and the material collected significantly advanced our knowledge about the RDB avifauna The third phase occurred from the 1970s to the first decade of the 21st century, when collection of specimens decreased sharply and the research activity slowly shifted from museums to universities, with a focus on ecology and natural history. We are now in a fourth, more pluralistic phase, in which research continues to be done by universities, Brazilian natural history museums have resumed their collection activity, and birdwatching has emerged as a popular activity in Brazil, producing a tremendous amount of data in a short period of time.

High Seasonal Variation of Plasma Testosterone Levels for a Tropical Grassland Bird Resembles Patterns of Temperate Birds.

AbstractTestosterone (T) is a sexual hormone capable of modulating several traits in birds, including aggressiveness and reproductive behavior. Although variation in T-related traits is well-known for temperate zone birds, this variation has not been extensively studied in tropical species. The campo miner (Geositta poeciloptera) is a threatened bird endemic to the grasslands of the South American Cerrado. We investigated the seasonal variation in plasma T levels and associated behavior in the campo miner, addressing the following questions: (1) Does the species exhibit seasonal variation in T profile? (2) Do males have higher plasma T levels than females, irrespective of season? (3) Are males with higher plasma T levels more aggressive than males with lower T levels? (4) Do males' plasma T levels decrease after females lay eggs? We found that T levels are higher during the breeding season than during the nonbreeding season and that males present higher T levels than females throughout the year. Such high T levels are associated with a higher probability to engage in aggressive behavior; however, T levels decline toward the egg-laying date and keep decreasing afterward. Higher T levels before egg laying are apparently related to territorial defense against invaders and extrapair copulations. With the beginning of parental care, T levels decrease, which is in line with previous observations that the species becomes less aggressive after egg laying. This study contributes to the understanding of environmental endocrinology of tropical birds, filling some knowledge gaps about the diverse Neotropical avifauna.

ATLANTIC BIRD TRAITS: a data set of bird morphological traits from the Atlantic forests of South America.

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra- and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820-2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities.

Soil attributes drive nest-site selection by the campo miner Geositta poeciloptera.

Substrate type is a key-factor in nest-site selection and nest architecture of burrowing birds. However, little is known about which factors drive nest-site selection for these species, especially in the tropics. We studied the influence of soil attributes on nest-site selection by the campo miner Geositta poeciloptera, an open grassland bird that builds its nests within soil cavities. For all nests found, we measured the depth of the nest cavity and the resistance of the soil to penetration, and identified the soil horizon in which the nest was located. In soil banks with nests, we collected soil samples for granulometric analysis around each nest cavity, while in soil banks without nests we collected these samples at random points. From 43 nests found, 86% were located in the deeper soil horizons (C-horizon), and only 14% in the shallower horizons (B-horizon). Granulometric analysis showed that the C-horizons possessed a high similar granulometric composition, with high silt and low clay contents. These characteristics are associated with a low degree of structural development of the soil, which makes it easier to excavate. Contrarily, soil resistance to penetration does not seem to be an important criterion for nest site selection, although nests in more resistant the soils tend to have shallower nest cavities. Among the soil banks analyzed, 40% of those without cavities possessed a larger proportion of B-horizon relative to the C-horizon, and their texture was more clayey. On the other hand, almost all soil banks containing nest cavities had a larger C-horizon and a silty texture, indicating that soil attributes drive nest-site selection by G. poeciloptera. Thus, we conclude that the patchy distribution of G. poeciloptera can attributed to the infrequent natural exposure of the C-horizon in the tropical region, where well developed, deep and permeable soils are more common.

Morphological variation of the Long-tailed Reed Finch Donacospiza albifrons (Vieillot, 1817) (Aves: Thraupidae).

The Long-tailed Reed Finch Donacospiza albifrons of south-central South America is patchily distributed in a variety of open habitats, usually near water. I present a detailed study of morphological variation based on 141 specimens, describing its plumage sequence and presenting notes on its molt and breeding. The Long-tailed Reed Finch shows no sexual dichromatism, but males average longer-winged than females. The species shows three distinct age-related plumages, which are redescribed here. It also shows marked individual variation in plumage and size, also showing marked plumage variation due to feather wear. Geographic variation is also marked, with birds from dry grasslands in northern highlands typically being larger, paler, and less streaked than birds from wet grasslands in southern lowlands, but there at some exceptions to this geographic pattern. I conclude that there is no solid basis for splitting the species into two or more taxa, and suggest considering the Long-tailed Reed Finch as a single, highly polymorphic species.

A cryptic new species of hummingbird of the Campylopterus largipennis complex (Aves: Trochilidae).

A new species of Campylopterus sabrewing is described from eastern Brazilian tropical dry forests occurring below 900 m asl. Its holotype (MZUSP 99024) is an adult female from Sítio Duboca (16°43'19''S, 43°58'20''W, elevation 840 m), municipality of Montes Claros, state of Minas Gerais. A taxonomic revision based on more than 1,000 museum specimens revealed that the new taxon, together with C. largipennis, C. diamantinensis and C. obscurus (with C. aequatorialis considered as a subjective junior synonym) should be ranked as species. We provide a key to permit easy identification of the four species. The new species is very similar to the parapatric C. diamantinensis of high altitude "campos rupestres" above 1,000 m asl, differing from it by its smaller size and longer light tail tips, as well as by sternum measurements. Given the several threats faced by the habitat to which the new species is endemic, we propose to consider it as Vulnerable under the IUCN criteria.

Variation of plumage patterns, geographic distribution and taxonomy of the Unicolored Blackbird (Aves: Icteridae).

The Unicolored Blackbird Agelasticus cyanopus (Vieillot, 1819) is a marsh bird with four allopatric subspecies restricted to lowlands in South America east of the Andes. I conducted a taxonomic revision of the species based on analysis of external morphological characters of 288 study skins, including all types available. My revision shows that: 1) Leistes unicolor Swainson, 1838, is a senior synonym of A. c. xenicus (Parkes, 1966) and, therefore, the correct name of the taxon should be A. c. unicolor (Swainson, 1838); 2) the range of A. c. unicolor (Swainson, 1838) is much wider than previously thought, extending from the mouth of the Rio Amazonas to the state of São Paulo, in southeastern Brazil, where it intergrades with A. c. atroolivaceus (zu Wied-Neuwied, 1831); 3) A. c. atroolivaceus extends its range well beyond the coast of Rio de Janeiro, reaching the coast of São Paulo, the central part of Minas Gerais, Bahia and Espírito Santo; and 4) specimens attributed to A. c. beniensis are highly variable, so this name must be considered a subjective junior synonym of the nominotypical taxon. Under the Biological Species Concept, two broadly parapatric species should be recognized, A. cyanopus and A. atroolivaceus (including unicolor as a subspecies). Under the Phylogenetic Species Concept or the General Lineage Concept of Species, the best taxonomic treatment is to recognize three species: A. cyanopus, A. atroolivaceus, and A. unicolor.

Evidence of hybrid origin for Tachyphonus nattereri Pelzeln, 1870 (Aves: Thraupidae).

Tachyphonus nattereri is one of the three "mystery birds" collected almost 200 years ago by J. Natterer in Brazil whose validity has been disputed in many publications over the last century. Known only from the male holotype and perhaps a female specimen without type status, it is currently treated as either a valid species, a subspecies or a doubtful taxon (an extreme of variation or an aberrant-colored individual). We reviewed the taxonomy of T. nattereri based on fieldwork near the type locality and a careful examination of the holotype and related museum specimens. Our extensive fieldwork revealed that no natural population found in the type locality matches the phenotype of T. nattereri. We found that the holotype is intermediate in plumage, morphometry and body shape between Tachyphonus cristatus and T. luctuosus, two sympatric species locally scarce and at their distributional edge around the type locality. We, therefore, suggest that T. nattereri is a hybrid. On the other hand, the purported female falls within the variation found in Tachyphonus c. madeirae, of which it probably represents an extreme phenotype.

Melanopareia bitorquata (d'Orbigny & Lafresnaye, 1837) is a distinct species: an appraisal of morphological variation in the Collared Crescentchest Melanopareia torquata (zu Wied-Neuwied, 1831) (Aves: Melanopareiidae).

The Collared Crescentchest Melanopareia torquata is a poorly known and inconspicuous species of open savannas and grasslands in central Brazil, Paraguay and Bolivia. Three subspecies are currently recognized, but their taxonomic limits, ranges and conservation status are far from well-established. This paper analyses individual and geographic variation in this species on the basis of body measurements and plumage coloration of 119 specimens. A clinal pattern of body size variation and considerable mensural overlap precludes a clear-cut separation between the two subspecies restricted to Brazil, and there is evidently sexual dichromatism in some Brazilian populations. However, M. t. bitorquata shows highly distinct plumage features in parapatry with other forms, strongly suggesting it should be treated as a full species.

Morphological data support the recognition of four species in the genus Sirystes Cabanis & Heine, 1859 (Aves: Tyrannidae).

Sirystes is a widespread genus in the Neotropical region. Historically, five subspecies were recognized in a single widespread species, but more recently four separate species have been recognized, based on vocalizations and limited morphological data. In this paper, we analyze individual and geographic variation in this genus on the basis of body measurements and plumage coloration of 514 specimens, including all name-bearing types available. We conclude that the four recently proposed species, S. sibilator, S. albogriseus, S. albocinereus, and S. subcanescens, can also be diagnosed by morphological data, corroborating more recent taxonomic treatments. We identified possible hybrids between S. sibilator and S. albocinereus from a narrow zone of contact in central Bolivia. We show that Sirystes sibilator atimastus Oberholser, 1902 represents a point on a cline within S. sibilator (Vieillot, 1818), and it is here regarded as a subjective junior synonym of the latter. We also provide new observations on the range and diagnosis of S. subcanescens, a name that has been frequently misused, and present a redescription of the four recognized species, as well as reviewing their range and natural history.

Morphological variation in the Cinnamon Tanager Schistochlamys ruficapillus Aves: Thraupidae).

The Cinnamon Tanager Schistochlamys ruficapillus inhabits semi-open grassy country, primarily in Brazil south of Amazonia. Three subspecies are currently recognized, one of which, S. r. sicki, is poorly known and endemic to the central Brazilian savannas (Cerrado). This paper analyses individual and geographic variation in this species on the basis of body measurements and plumage coloration. Larger birds are usually found farther south and at higher elevations, while smaller birds are found farther north and at lower elevations, as predicted by Bergmann's rule. Nevertheless, some unexpectedly small individuals (referable to S. r. sicki) can be found in central Brazil. Individual and geographical variation in plumage coloration is substantial, but it is not closely tied to variation in body size. Therefore, given the large number of specimens intermediate between the three subspecies, we propose to consider the Cinnamon Tanager a monotypic but highly variable species. The recognition of three subspecies by previous taxonomists was due to small sample sizes associated with large gaps in sampling. 

Taxonomy, distribution, natural history and conservation of the Russet-mantled Foliage-gleaner Syndactyla dimidiata (Pelzeln, 1859) (Aves: Furnariidae).

Russet-mantled Foliage-gleaner is an extremely poorly known species, the range of which is centered in the Brazilian Cerrado, where it inhabits riparian forests. Two subspecies are recognized, but the limits of their ranges are controversial. Furthermore, it was recently suggested that the species is one of the few in the family Furnariidae to show sexual dichromatism. In this paper we examined the plumage coloration and morphometrics of 33 study skins (85% of the available specimens). We conclude that the geographic variation and sexual dichromatism reported for S. dimidiata originated from misinterpretation of the plumage variation observed in this species, which is best considered monotypic. We also present natural history data on Russet-mantled Foliage-gleaners and suggest considering it a globally Vulnerable species.

The birds of Fazenda Brejão: a conservation priority area of Cerrado in northwestern Minas Gerais, Brazil / Aves da Fazenda Brejão: uma área prioritária para conservação do Cerrado no noroeste de Minas Gerais, Brasil

The Cerrado is now considered the most threatened biome of South America. Northwestern Minas Gerais state, in southeastern Brazil, still harbors large areas of extreme importance for biological conservation of the Cerrado. The current study provides the first thorough assessment of the avifauna of a large remnant of Cerrado vegetation in this region, the Fazenda Brejão. Data are based on a bird survey conducted from November 1998 to January 2007. This area is a private property of 20.000 ha preserved that lies in a region recognized for its palm groves, a pristine Cerrado (savannah-like vegetation) and gallery forests. Bird censuses were carried out through random transects censuses, mist-net captures and recording bird vocalizations. It was recorded 273 species, belonging to 56 families. This represents 32 percent of all 857 bird species recorded for the Cerrado. Palm groves held approximately 42 percent of all recorded species. We also recorded endemic species of Cerrado as well as adjacent biomes such as the Atlantic Forest and the Caatinga. Regional threatened species were also recorded such as the Greater Rhea Rhea americana, the Chestnut-bellied Guan Penelope ochrogaster, the Bare-faced Curassow Crax fasciolata, the Black-and-white Hawk-eagle Spizastur melanoleucus, the Blue-and-yellow Macaw Ara ararauna, the Yellow-faced Parrot Alipiopsitta xanthops and the Minas Gerais Tyrannulet Phylloscartes roquettei. This species diversity reveals the biological importance of the region. The establishment of a natural reserve in the region will be an essential measure to guarantee the biological conservation of one of the best preserved areas of Cerrado to date in southeastern Brazil.

O Cerrado é considerado um dos biomas mais ameaçados da América do Sul. O noroeste do estado de Minas Gerais, sudeste do Brasil, ainda possui grandes áreas de importância biológica extrema para a conservação do Cerrado. Este estudo apresenta o primeiro levantamento sistemático da avifauna de uma grande área remanescente de Cerrado nesta região, a Fazenda Brejão. Os dados são baseados em levantamentos conduzidos de novembro de 1998 a janeiro de 2007. A área é uma propriedade privada de mais de 20.000 ha preservados que se situa numa região conhecida por suas veredas de buritizais, Cerrado e matas ciliares preservados. O censo de aves foi feito em transeções aleatórias, captura e marcação de indivíduos e gravação de vocalizações. Foram registradas 273 espécies de 56 famílias. O total representa 32 por cento das 857 espécies já registradas no Cerrado. As veredas de buritizais contêm aproximadamente 42 por cento de todas as espécies registradas. Também foram registradas espécies localmente ameaçadas, como a ema Rhea americana, o jacu-de-barriga-castanha Penelope ochrogaster, o mutum-de-penacho Crax fasciolata, o gavião-pato Spizastur melanoleucus, a arara-canindé Ara ararauna, o papagaio-galego Alipiopsitta xanthops, e o cara-dourada Phylloscartes roquettei. Essa diversidade de espécies revela a importância biológica da região. A consolidação de unidades de conservação na região será medida essencial para garantir a conservação da biodiversidade de umas das áreas mais bem preservadas do Cerrado até o momento no sudeste do Brasil.

Predicted climate-driven bird distribution changes and forecasted conservation conflicts in a neotropical savanna.

Climate-change scenarios project significant temperature changes for most of South America. We studied the potential impacts of predicted climate-driven change on the distribution and conservation of 26 broad-range birds from South America Cerrado biome (a savanna that also encompass tracts of grasslands and forests). We used 12 temperature or precipitation-related bioclimatic variables, nine niche modeling techniques, three general circulation models, and two climate scenarios (for 2030, 2065, 2099) for each species to model distribution ranges. To reach a consensus scenario, we used an ensemble-forecasting approach to obtain an average distribution for each species at each time interval. We estimated the range extent and shift of each species. Changes in range size varied across species and according to habitat dependency; future predicted range extent was negatively correlated with current predicted range extent in all scenarios. Evolution of range size under full or null dispersal scenarios varied among species from a 5% increase to an 80% decrease. The mean expected range shifts under null and full-dispersal scenarios were 175 and 200 km, respectively (range 15-399 km), and the shift was usually toward southeastern Brazil. We predicted larger range contractions and longer range shifts for forest- and grassland-dependent species than for savanna-dependent birds. A negative correlation between current range extent and predicted range loss revealed that geographically restricted species may face stronger threat and become even rarer. The predicted southeasterly direction of range changes is cause for concern because ranges are predicted to shift to the most developed and populated region of Brazil. Also, southeastern Brazil is the least likely region to contain significant dispersal corridors, to allow expansion of Cerrado vegetation types, or to accommodate creation of new reserves.

Biologia reprodutiva de Tyrannus savana (Aves, Tyrannidae) em cerrado do Brasil Central / Breeding biology of Tyrannus savana (Aves, Tyrannidae) in cerrado of Central Brazil

The Fork-tailed Flycatcher Tyrannus savana (Tyrannidae) is a migratory passerine that occurs in central Brazil between August and February. Its breeding biology is still little known, and this study reports data on breeding season, incubation and nestling periods, nest and egg characteristics, nest success and predation rate. We searched for nests at ôEstação Ecológica de Águas Emendadasõ (ESECAE) and its surroundings, Distrito Federal, Brazil, in the breeding seasons of 2002 to 2007. We monitored 78 nests each 2-4 days. Breeding season started in late September and lasted until mid December. Incubation lasted 13.6 ± 0.4 days (n = 21) (mean ± SE) and nestling period lasted 15 ± 0.4 days (n = 27). Most nests (n = 39) were found in ôcerrado raloõ vegetation and were built on plants of the genus Kielmeyera. Clutch size ranged from 1 to 3 eggs, with an average of 2.5 ± 0.3 eggs. Egg length and width averaged 22.2 ± 0.2 mm and 15.8 ± 0.1 mm (n = 6), respectively, and the average weight was 3.0 ± 0.2 g (n = 5). Thirty (52.5%) nests were successful, 24 (43.9%) were predated and only two (3.7%) were abandoned. Egg success was 39.2 ± 1.4% and mean hatching rate was 0.6 ± 0.2 fledglings/egg. Overall productivity was 1.0 ± 0.3 fledglings per nest, and fecundity rate was 1.4 ± 0.4 fledglings per female. Nest success (Mayfield method) was 45.9% ± 1.1, with no significant difference between the average daily survival rate between egg and nestling periods. Several of the estimated parameters for T. savana revealed to be different than expected for a tropical flycatcher.

A tesourinha Tyrannus savana é um Passeriforme (Tyrannidae) migratório que ocorre no Planalto central entre os meses de agosto e fevereiro. Sua biologia reprodutiva é ainda pouco conhecida e foi abordada pelo presente estudo quanto aos seguintes aspectos: período reprodutivo, tamanho da ninhada, tempo de incubação e de permanência dos ninhegos no ninho, características dos ninhos e ovos, taxa de sucesso dos ninhos e taxa de predação. O estudo foi realizado na Estação Ecológica Águas Emendadas e em fragmentos do entorno, DF, nas estações reprodutivas de 2002 a 2007. Os ninhos (n = 78) foram monitorados em intervalos de 2-4 dias. O período reprodutivo estendeu-se de setembro a dezembro. O período médio de incubação foi de 13,6 ± 0,4 dias (n = 21) (média ± EP), e a permanência dos ninhegos no ninho foi de 15 ± 0,4 dias (n = 27). A maioria dos ninhos (n = 39) foi encontrada em cerrado ralo e em plantas-suporte do gênero Kielmeyera. O tamanho da ninhada variou de 1 a 3 ovos com média de 2,5 ± 0,3 ovos. O comprimento e a largura média dos ovos foram de 22,2 ± 0,2 mm e 15,8 ± 0,1 mm (n = 6), respectivamente, e o peso médio foi de 3,0 ± 0,2 g (n = 5). Trinta ninhos (52,5%) tiveram sucesso, 24 (43,8%) foram predados e apenas dois (3,7%) foram abandonados. O sucesso dos ovos foi de 39,2 ± 1,4%, sendo a taxa de eclosão de 0,6 ± 0,2 filhotes/ovo, a fecundidade de 1,5 ± 0,4 filhotes/fêmea e da produção anual de filhotes de 1,0 ± 0,3 filhotes/ninho. O sucesso dos ninhos (método de Mayfield) foi de 45,9% ± 1,1, não havendo diferença significativa entre a taxa média de sobrevivência diária nas fases de ovo e ninhego. Diversos parâmetros estimados para T. savana revelaram ser diferentes do esperado para um tiranídeo tropical.

Sobre a ocorrência de Philornis angustifrons e P. deceptiva (Diptera, Muscidae) em ninhos de Suiriri affinis e S. islerorum (aves, tyrannidae), no cerrado do Distrito Federal, Brasil / On the ocurrence of Philornis angustifrons and P. deceptiva (Diptera, Muscidae) in nests of Suiriri affinis and S. islerorum (Aves, Tyrannidae) in the savanna of Distrito Federal, Brazil

The first report of Philornis angustifrons and P. deceptiva infesting nests of Suiriri affinis and S. islerorum in area of Distrito Federal's savanna is presented. It is known that larvae of these species have a strict relationship of parasitism with birds. The pupae were collected after the abandonment of the nests and the flies emerged in a period of about 13 days.