Extra-pair paternity in a Neotropical rainforest songbird, the White-necked Thrush Turdus albicollis (Aves: Turdidae)

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

Aves como potenciais dispersoras de sementes de Ocotea pulchella Mart. (Lauraceae) numa área de vegetação de cerrado do sudeste brasileiro

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.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Reproductive behavior of the Red-crested Finch Coryphospingus cucullatus (Aves: Thraupidae) in southeastern Brazil

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

Nest site selection and reproductive parameters of the threatened Atlantic Royal Flycatcher (Onychorhynchus swainsoni) and their significance for conservation

Abstract Background Patterns of rarity can be explained by reproductive rates, levels of endemism, and habitat specificity, and knowledge on these parameters is important to understand the levels of vulnerability of each species and to formulate conservation strategies. Here, we studied nest-site selection and breeding biology of the Atlantic Royal Flycatcher (Onychorhynchus swainsoni), a poorly known vulnerable bird endemic to the Brazilian Atlantic Forest. Methods We addressed nest site selection in three different levels: first, we searched for nests near and far from water to investigate whether birds could select water proximities to construct nests; second, we examined if they could select certain streams in detriment of others, and we analyzed the characteristics of used and non-used streams, and third, in streams in which nests were found, we addressed nest site selectivity by comparing a number of parameters between nest sites and random sites. Further, we provide information on breeding biology parameters related to annual fecundity. Results During five breeding seasons, we found 23 nests in a well-preserved forest continuum. All of the nests were constructed above water, and they were found in streams that were about 4 m in width, instead of smaller streams with about 1.5 m in width. Modeling analyses revealed that within the used streams, nests were constructed in sites with lower vegetation density in relation to random points, while stream width, water speed, and canopy cover presented no significant correlation. Atlantic Royal Flycatchers in our study had a 22-day incubation period and 24 to 27-day nestling period. Overall nest survival was comparatively high (62%), but clutch size was small (N = 2 eggs) and double-brooding was unlikely, which resulted in a low annual fecundity (1.4 ± 0.9 fledglings per reproductive female). Along the nesting streams, we found an average of 1.62 ± 0.07 breeding pairs/km. Conclusions These data suggest that nesting habitat specificity and low annual fecundity are among the factors contributing to the rarity of the Atlantic Royal Flycatcher in large forest continuums and to its absence in fragmented environments. It reinforces the importance of large well-preserved forest continuums for the conservation of habitat specialist Atlantic Forest bird species

Atlantic forest fragmentation and genetic diversity of an isolated population of the Blue-manakin, Chiroxiphia caudata (Pipridae), assessed by microsatellite analyses

Habitat fragmentation is predicted to restrict gene flow, which can result in the loss of genetic variation and inbreeding depression. The Brazilian Atlantic forest has experienced extensive loss of habitats since European settlement five centuries ago, and many bird populations and species are vanishing. Genetic variability analysis in fragmented populations could be important in determining their long-term viability and for guiding management plans. Here we analyzed genetic diversity of a small understory bird, the Blue-manakins Chiroxiphia caudata (Pipridae), from an Atlantic forest fragment (112 ha) isolated 73 years ago, and from a 10,000 ha continuous forest tract (control), using orthologous microsatellite loci. Three of the nine loci tested were polymorphic. No statistically significant heterozygote loss was detected for the fragment population. Although genetic diversity, which was estimated by expected heterozygosity and allelic richness, has been lower in the fragment population in relation to the control, it was not statistically significant, suggesting that this 112 ha fragment can be sufficient to maintain a blue-manakin population large enough to avoid stochastic effects, such as inbreeding and/or genetic drift. Alternatively, it is possible that 73 years of isolation did not accumulate sufficient generations for these effects to be detected. However, some alleles have been likely lost, specially the rare ones, what is expected from genetic drift for such a small and isolated population. A high genetic differentiation was detected between populations by comparing both allelic and genotypic distributions. Only future studies in continuous areas are likely to answer if such a structure was caused by the isolation resulted from the forest fragmentation or by natural population structure