Resumo A determinação dos riscos relativos de extinção dos táxons ameaçados é importante para o delineamento de ações de recuperação e para o direcionamento dos investimentos em conservação. O Brasil é o país que possui o maior número de táxons ameaçados de aves, no entanto, informações sobre aspectos demográficos são inexistentes para a maioria deles. Neste trabalho são apresentadas estimativas de densidades populacionais, baseadas no método de amostragem por distância, para três táxons ameaçados de extinção endêmicos do Centro de Endemismo Pernambuco (CEP), a região mais degradada de toda a Mata Atlântica. Os táxons analisados foram a choca-lisa Thamnophilus aetiops distans (Ameaçada), o flautim-marrom Schiffornis turdina intermedia (Vulnerável) e a maria-de-barriga-branca Hemitriccus griseipectus naumburgae (Vulnerável). Os números de indivíduos/ha estimados para um fragmento de floresta de aproximadamente 1000 ha foram respectivamente 0,21, 0,14 e 0,73. Com isto, foi possível confirmar a premissa de que mesmo táxons classificados em uma mesma categoria de ameaça com base apenas em informações de hábitats podem possuir densidades populacionais bastante divergentes e portanto diferentes graus de riscos de extinção. Embora as densidades populacionais possam variar entre fragmentos, a extrapolação destes dados para toda a área do CEP confirmou a classificação de Vulnerável para o flautim-marrom e indicou as categorias Vulnerável e Pouco Preocupante para a choca-lisa e para a maria-de-barriga-branca, sugerindo que para as duas últimas, as classificações atuais baseadas nos tamanhos das suas Áreas de Ocupação (Ameaçada e Vulnerável) devem prevalecer.

Abstract Determining the relative risks of extinction of declining taxa is important to delineate conservation priorities and to guide the investments in conservation. Brazil concentrates the greatest number of endangered avian taxa on Earth, yet demographic information is lacking for most of them. Here we present distance-sampling population density estimates for three endangered bird taxa endemic to the Pernambuco Endemism Center (PEC), the most critically disturbed Atlantic Forest region. The analyzed taxa were the White-shouldered Antshrike Thamnophilus aetiops distans (Endangered), the Brown-winged Mourner Schiffornis turdina intermedia (Vulnerable), and the White-bellied Tody-tyrant Hemitriccus griseipectus naumburgae (Vulnerable). The estimated numbers of individuals/ha in an approximately 1,000 ha forest fragment were 0.21, 0.14, and 0.73, respectively. Our findings corroborated the premise that even taxa classified in similar threat categories based on habitat characteristics alone can have different population densities and consequently, divergent risks of extinction. Although population densities can vary among fragments, the extrapolation of our data to the whole PEC confirmed the Vulnerable status of the Brown-winged Mourner, and indicated the Vulnerable and Least Concern categories for the White-shouldered Antshrike and for the White-bellied Tody-tyrant, suggesting that for the two later taxa, the current classifications (Endangered and Vulnerable) based on their Areas of Occupancy must prevail.

ABSTRACT Information on the breeding biology of most Neotropical birds, and interpopulation comparisons, are insufficient. The Helmeted Manakin, Antilophia galeata (Lichtenstein, 1823), is a forest understory passerine commonly found in the gallery forests of the tropical savanna-like Cerrado biome. We provide information about the nesting phenology, nesting cycle, nests, eggs, nestlings, and nest-site characteristics of a population of the Helmeted Manakin in the state of São Paulo, southeastern Brazil. During two breeding seasons we found 16 active, and 30 inactive nests. Breeding activities occurred from mid- August to mid- January, and nests were constructed in bushes and saplings in the forest’s understory, 0.45-3.48 m above ground (1.56 ± 0.66 m). Clutch size was two eggs, which were laid in intervals of one to three days. Three remarkable patterns of interclutch egg color and marking variations were observed. The incubation period of two nests was 18 and 19 days, and nestling periods were 16.3 ± 0.6 days (16-17 days, n = 3 nests). The apparent nest survival of 11 thoroughly monitored nests was 36.4%. In addition to the first description of the interclutch egg pattern variations, the following information differs from previous literature data: egg laying interval and nestling periods. Our data contribute to the overall knowledge of the variations in breeding parameters of the Helmeted Manakin.

ABSTRACT The Chestnut-capped Blackbird, Chrysomus ruficapilus (Vieillot, 1819), is a common bird species in flooded areas of South America. Data on its reproductive parameters have been reported mainly for rice paddies from Uruguay and southern Brazil, where reproductive phenology might have been influenced by the chronology of agricultural activities. Here we provide reproductive data for a population in a natural marshland from São Paulo state, southeastern Brazil. A total of 45 active nests were monitored between December 2017 and April 2018. Clutch size was 2.8 ± 0.44. Incubation and nestling periods were respectively 11.8 ± 0.39, and 12.3 ± 0.75 days, and overall nesting success was 65%. The reproductive season lasted about five months, which is longer than that observed in rice paddies from southern Brazil. This suggests that the reproductive phenology has been underestimated before. Although clutch sizes were bigger in our study population than that from rice paddies from southern Brazil, nest survival was higher in the artificial habitat, suggesting that the Chestnut-capped Blackbird can obtain benefits from nesting in artificial habitats.

ABSTRACT Even though nest architecture has been useful for phylogenetic inferences among the Thamnophilidae (Aves: Passeriformes), the nests of only three out of five species of Myrmoderus (Ridgway, 1909) are known to science. Here we describe the nests, eggs, and nestling of the Squamate Antbird Myrmoderus squamosus (Pelzeln, 1868). Two nests were bulky bottom-supported cups, measuring 7.3 and 12 cm in maximum outside diameter, with a noticeably smaller egg cup, and they were placed within the crown of short, broad-leafed plants. Eggs were short-oval, with chalky white background color, and purple blotches and streaks more concentrated in the large end. One nestling was dark reddish grey, with bluish white feet, pinkish gray tarsi, and a blackish bill with bright yellow rictal flanges. In face of the great diversity of nest types found among the Thamnophilidae, we concluded that the nest of M. squamosus was similar to those of other congeners, giving support to this currently phylogenetically-defined genus.

ABSTRACT Identification of the predators of bird nests is essential to test ecological and evolutionary hypotheses and to make practical management decisions. A variety of nest monitoring devices have been proposed but many remain difficult to set up in the field. The aim of this study was to test camera traps as a potential tool to study predation of natural nests in a tropical rainforest environment. Specifically, we registered the predators, assessed their size range, and we compared the use of one and two cameras per nest. Of 122 nests from 24 bird species, 45 (37%) were depredated, and the cameras recorded the predator species in 29 of the total of depredated nests (64%). We identified predators in eight of 16 depredated nests (50%) in which we used one camera trap per nest, and we identified predators in 21 of 29 depredated nests (72%) when we used two camera traps per nest. The predators included six species of birds and six species of mammals, with body masses varying from 20 g to 16.5 kg. Causes for 10 of the 16 detection failures were identified and are discussed. These results suggest that camera traps are viable tools to investigate nest predation in a tropical rainforest area.

ABSTRACT Despite the fact that E. chlorotica (Linnaeus, 1766) is common and widely distributed in South America, the reproductive aspects of the species are poorly documented. Here we present data on 18 active nests found from August to February, between 2007 and 2012. Nests were globular with a lateral entrance, and measured 97.9 ± 14.4 mm in outside height, 110.6 ± 11.6 mm in outside diameter, and were 4.88 ± 2.09 m above ground. They were often supported from bellow and were composed mainly of tiny dry leafs and leaflets, fine petioles, and plumed seeds, all compacted with spider web silk. Eggs were laid on consecutive days or with one day interval, and clutch size varied from 1-3 eggs (2.1 ± 0.6, n = 9 nests). Only females incubated the eggs, but both sexes were involved in nest construction and nestling attendance at similar rates. Incubation and nestling periods were 14 and 21 days, respectively, and overall nest survival probability was 5%. A vespiary used for nesting was not occupied by wasps and nest material was deposited only to form the incubatory chamber. Although nesting near wasps or bees is a widespread strategy among birds in general, nesting inside the nests of social insects is a poorly documented behavior.

ABSTRACT Several behavioral aspects of the Red-crested Finch Coryphospingus cucullatus (Statius Müller, 1776) are poorly studied. Here we provide reproductive information on 16 active nests. This information may be valuable to elucidate the phylogenetic relationships of this bird, and to design plans to manage it. Nesting activities occurred from October to February. Clutches consisted of two to three eggs (2.06 ± 0.25), which were laid on consecutive days. Incubation usually started the morning the females laid their last egg and lasted 11.27 ± 0.47 days. Hatching was synchronous, or happened at a one-day interval. The nestling stage lasted 12 ± 0.89 days. Only females incubated the eggs and they fed the young more often than the males did. Overall nesting success, from incubation to fledging, was 28.2%. Nest architecture and egg color proved to be diagnostic characteristics of Coryphospingus , supporting its maintenance as a distinct genus within the recently proposed sub-family Tachyphoninae. Red-crested Finches showed a preference for certain nesting sites, i.e., forest borders or a Cerrado in late regeneration stage. This information can be useful to programs aiming to release illegally trapped individuals.

ABSTRACT Over the last two decades, several studies have shown that the mating systems of various birds are more complex than previously believed, and paternity tests performed with molecular techniques have proved, for instance, that the commonly observed social monogamy often presents important variations, such as extra-pair paternity. However, data are still largely biased towards temperate species. In our study, at an area of the Brazilian Atlantic Forest, we found broods containing at least one extra-pair young (EPY) in the socially monogamous White-necked Thrush Turdus albicollis (Vieillot, 1818). Paternity tests using six heterologous microsatellite loci revealed that four of 11 broods (36.4%) presented at least one extra-pair young (EPY). This rate of EPY is within the range found for other studies in the tropics. This is one of the few studies that present detailed paternity analyses of a Neotropical rainforest passerine. Our findings corroborate the early insights that breeding strategies involving cheating can also be widespread among Neotropical socially monogamous songbirds.

Embora os estudos de frugivoria e dispersão de sementes sejam importantes para a realização de planos de manejo e recuperação de ambientes degradados, pouco tem sido pesquisado sobre o assunto no cerrado brasileiro. Neste trabalho são apresentados aspectos da frugivoria e dispersão das sementes de Ocotea pulchella Mart. (Lauraceae) por aves. Treze espécies de aves foram registradas consumindo os frutos de O. pulchella em 72 horas de observação focal, entre os meses de agosto e outubro de 1999, numa área de cerrado da região central do estado de São Paulo (21º58' S, 47º52' W), Brasil. As principais espécies potencialmente dispersoras foram o sabiá-pardão, Turdus leucomelas (Muscicapidae), o sabiá-docampo, Mimus saturninus (Mimidae), o bem-te-vi, Pitangus sulphuratus (Tyrannidae) e as guaracavas, Elaenia spp. (Tyrannidae). Não foram encontradas variações significativas no número de visitas nos diferentes intervalos de hora quando todas as espécies foram analisadas em conjunto e quando cada espécie foi analisada separadamente. Não houve variação significativa também no tempo de permanência sobre as plantas entre as diferentes espécies de aves. A taxa de consumo diferiu significativamente entre elas, tendo sido encontrada correlação positiva significativa entre o peso das diferentes espécies e o número médio de frutos consumidos por visita. O tempo de permanência sobre a planta e o número de frutos consumidos foram positivamente correlacionados para Elaenia spp., para a maria-cavaleira, Myiarchus tyrannulus (Tyrannidae) e para o sabiá-laranjeira, Turdus rufiventris (Muscicapidae). Embora espécies primariamente frugívoras não tenham sido observadas consumindo os frutos de O. pulchella, as espécies oportunistas pareceram favorecer a eficiência da dispersão, mantendo altas freqüências de visitas, altas taxas de consumo e permanecendo por curtos períodos de tempo sobre as plantas.

Studies on frugivory and seed dispersal are extremely important for management plans, but few studies have been developed in the Brazilian cerrado. In this paper we describe the frugivory and seed dispersal of Ocotea pulchella Mart. (Lauraceae) by birds in a cerrado area in São Paulo state (21º58' S, 47º52' W), southeastern Brazil. In 72 hours of focal observations, from August to October 1999, we recorded 411 visits of 13 different bird species consuming the fruits of O. pulchella. The main potential seed dispersers were the Pale-breasted Thrush, Turdus leucomelas (Muscicapidae), the Chalk-browed Mockingbird, Mimus saturninus (Mimidae), the Great Kiskadee, Pitangus sulphuratus (Tyrannidae) and the Elaenias, Elaenia spp. (Tyrannidae). We did not find significant difference in the frequency of visits at different hour intervals throughout the day when all of the species were pooled together and when the species were individually considered. The bird species did not differ in the time they spent foraging on the plants. The number of fruits consumed in each visit differed among species and there was positive correlation between avian body mass and mean number of consumed fruits in these visits. The time spent on plants was positively correlated to the number of consumed fruits by Elaenia spp., Brown-crested Flycatcher, Myiarchus tyrannulus (Tyrannidae) and the Rufous-bellied Thrush, Turdus rufiventris (Muscicapidae). Although specialist frugivorous birds have not been observed consuming O. pulchella, generalist species were potential seed dispersers, presenting high frequency of visits, high fruit consume and shortened visit periods.