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Secondary contact between species often results in the formation of a hybrid zone, with the eventual fates of the hybridizing species dependent on evolutionary and ecological forces. We examine this process in the Amazon Basin by conducting the first genomic and phenotypic characterization of the hybrid zone formed after secondary contact between two obligate army-ant-followers: the White-breasted Antbird (Rhegmatorhina hoffmannsi) and the Harlequin Antbird (Rhegmatorhina berlepschi). We found a major geographic displacement (∼120 km) between the mitochondrial and nuclear clines, and we explore potential hypotheses for the displacement, including sampling error, genetic drift, and asymmetric cytonuclear incompatibilities. We cannot exclude roles for sampling error and genetic drift in contributing to the discordance; however, the data suggest expansion and unidirectional introgression of hoffmannsi into the distribution of berlepschi.

The Jurua River is the third largest white-water tributary of the Amazon River, yet, historically, it has not been considered an important barrier for bird communities. The upper region of the Jurua River was the focus of two ornithological collections in the early twentieth century, but the middle region, where the river and surrounding varzea flooded forest widen, has remained largely unexplored by ornithologists. Inspired by Dr. Emilie Snethlage, whose ornithological expeditions to Amazonian rivers during the early twentieth century were foundational in documenting the importance of river barriers, we undertook a month-long expedition to the middle Jurua River. We collected the first modern specimens, high-quality tissues, and sound recordings of birds from the middle Jurua region. Combining our data with those from previous collections, we present the first comprehensive inventory of bird species from the Jurua region, document several significant range extensions, and report the first evidence that the middle Jurua River acts as a barrier in at least four species complexes of terra firme upland forest birds. Our findings have important taxonomic and biogeographic implications for birds of the Jurua region and southwestern Amazon basin.

Altitudinal migration in birds comprises seasonal movements between breeding and non-breeding areas in mountainous regions, attributed to biotic and abiotic factors. Different authors have suggested the existence of altitudinal migration between high and low areas of the mountains of the Atlantic Forest, with movement from high to low during the winter when birds would be fleeing the cold and in search of food, but there is no documented evidence. Through recaptures of understory birds, we investigated possible altitudinal migration in a region of the Atlantic Forest in Southeast Brazil. Twenty mist-nets were set at four locations between 15 and 729 m a.s.l. during 143 days of field work, distributed over 54 months and covering all seasons of the year. A total of 1946 birds (98 species) were captured/banded with 558 being recaptured (28.6%; 45 species). However, only 42 of the recaptures were at a different elevation. Most of the movements were of short distances and performed only once by birds, showing no seasonal pattern. These movements may be better interpreted as daily movements undertaken by birds of mixed-species flocks looking for food or moving around their respective home-ranges. Our results show that mist-nets may not be an effective tool in detecting altitudinal movements of birds and that other methods should be evaluated for this purpose.

Clytoctantes atrogularis Lanyon, Stotz and Willard, 1990 (Thamnophilidae) is one of the most mysterious and poorly known birds of the Neotropics. Endemic to Amazonian Brazil, it was known only from the holotype and two sight records at the type locality in Rondonia, and a sighting of a pair with a recording on the Sucunduri River in Amazonas. Here we review the distribution and report five new records in the states of Mato Grosso, Amazonas, and Rondonia, considerably increasing the known range of the species. We present the first detailed descriptions of males, for which the plumage was previously unknown. The records presented herein were made in terra firme forest with understories dominated by Lepidocaryum palms and also with sparse Guadua spp. of bamboo, demonstrating that the bird species occurs in habitats other than those previously described. Stomach contents of six individuals included mostly ants and their eggs, possibly obtained by opening stems of Guadua spp. The high rate of deforestation that characterizes a large part of the range of C. atrogularis could be causing declines in local populations.

Made available in DSpace on 2018-11-12T17:28:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2017. Added 1 bitstream(s) on 2018-11-12T17:36:01Z : No. of bitstreams: 1 S1984-46702017000100309.pdf: 3250536 bytes, checksum: 4333e8e56132d2bc2496715bb3a81790 (MD5) ABSTRACT Stretching for more than 10,000 ha in the Metropolitan Area of São Paulo, southeastern Brazil, Serra da Cantareira comprises the largest native urban rainforest in the World, harboring a rich and diverse Atlantic Forest avifauna. Despite its closeness to major urban areas, few bird surveys have been conducted there. In this article we present an updated compilation of all bird species recorded for Serra da Cantareira, including personal records from the authors. A total of 326 species have been recorded for Serra da Cantareira since 1901; of these, nine have not been sighted there for the last two decades. The number of bird species endemic to the Atlantic Forest is high (80), and seven of its species are globally threatened. According to multivariate analyses the species diversity at Serra da Cantareira is similar to other regions of the Atlantic Forest, such as Carlos Botelho and Intervales state parks, where the vegetation is also ombrophilous dense forest. We discuss local changes in the avifaunal composition over the last decades and suggest the incorporation of large forest remnants to the Cantareira State Park to mitigate the impact of the northern section of Rodoanel Mário Covas, a highway (SP-21) that will soon be operational and will negatively impact the biodiversity of Serra da Cantareira. Universidade Estadual Paulista Departamento de Ecologia Lousiana State University Museum of Natural Science Unaffiliated BirdLife SAVE Brasil Universidade de São Paulo Instituto de Biociências Departamento de Zoologia Universidade de São Paulo Museu de Zoologia Universidade Estadual Paulista Departamento de Ecologia

O complexo Picumnus exilis é composto por seis táxons: P. e. exilis, P. e. pernambucensis, P. e. alegriae, P. e. buffonii, P. e. undulatus e P. e. clarus, ou sete se P. e. salvini for considerado sinônimo sênior de P. nigropunctatus. Esses táxons se distribuem desde o extremo leste Colombiano, passando pela Venezuela, Guianas e até o nordeste brasileiro, e são caracterizados pelo dorso de plumagem esverdeada, ventre esbranquiçado ou amarelado, e barrado ou maculado de negro; os machos apresentam a fronte vermelha e/ou alaranjada. O presente trabalho tem como objetivo revisar a taxonomia desse complexo através da análise de caracteres de plumagem e morfométricos. Foram estudados 495 espécimes, depositados nas principais coleções ornitológicas. Foram determinados 18 caracteres de plumagem, 12 dos quais mostraram-se informativos, além de caracteres morfométricos. O estudo dos caracteres relacionados à plumagem aponta para a existência de cinco táxons. Picumnus exilis (Lichtenstein, 1823), que ocorre próximo ao litoral da Bahia e de Sergipe. Picumnus pernambucensis Zimmer, 1947 ocorre ao norte do rio São Francisco (AL, PE e PB). Picumnus buffonii Lafresnaye, 1845 ocorre no escudo guianense, ao leste do rio Branco e também ao sul do rio Amazonas, a leste do rio Tocantins (PA e MA). Picumnus undulatus Hargitt, 1889 é encontrado entre os rios Branco, Negro e Orinoco, enquanto Picumnus obsoletus Allen, 1892, ocorre em baixas altitudes desde o delta do Orinoco até o extremo nordeste venezuelano (Delta Amacuro, Monagas e Sucre). As subespécies P. e. alegriae Hellmayr, 1929, e P. e. clarus Zimmer & Phelps, 1946, foram sinonimizados, respectivamente, à P. buffonii e P. undulatus. Tanto P. e. salvini Hargitt, 1893, como P. nigropunctatus Zimmer & Phelps, 1950, foram considerados sinônimos juniores de Picumnus obsoletus Allen, 1892. Similaridades entre as espécies aqui determinadas e outros Picumnus apontam para um parafiletismo do complexo P. exilis da maneira como tratado pela literatura. Em adição, os resultados demonstram a necessidade de uma revisão taxonômica e filogenética que englobe todo o gênero Picumnus. The Picumnus exilis complex is composed by six subspecies: P. e. exilis, P. e. pernambucensis, P. e. alegriae, P. e. buffonii, P. e. undulates and P. e. clarus; or seven if one considers P. e. salvini as a senior synonym of P. nigropunctatus. These taxa are found from easternmost Colombia and through Venezuela and Guianas, and north towards northeastern Brazil. They are characterized by a greenish back, whitish or yellowish belly (barred or tainted with black); males exhibit red and/or orange forehead. This work aims to review the taxonomy of this complex on the basis of morphometric and plumage characters analyses. I analyzed 495 specimens housed in the main ornithological collections. A total of 18 plumage characters were found, 12 of them proved to be informative. The results suggested the existence of five taxa. Picumnus exilis (Lichtenstein, 1823), which occurs near the coasts of Bahia and Sergipe. Picumnus pernambucensis Zimmer, 1947, found north of the São Francisco River (Alagoas, Pernambuco and Paraiba). Picumnus buffonii Lafresnay, 1845 occurs in the Guyana Shield, East of the Branco River and South of the Amazonas River to the East of the Tocantins River (Pará and Maranhão). Picumnus undulates Hargitt, 1889 is found between the Branco, Negro and Orinoco Rivers. The fifth taxon is Picumnus obsoletus Allen, 1892, which occurs at low altitutes and ranges from the Orinoco Delta north to far northeast Venezuela (Delta Amacuro, Monagas and Sucre). The subspecies P. e. alegriae Hellmayr, 1929, and P. e. clarus Zimmer & Phelps, 1946 have been synonymized with P. buffonii and P. undulates, respectively. Furthermore, both P. e. salvini Hargitt, 1893, and P. nigropunctatus Zimmer & Phelps, 1950, proved to be junior synonyms of Picumnus obsoletus Allen, 1892. Similarities between these species and other Picumnus point out to a paraphyletic P. exilis complex. These results highlight the need of taxonomic and phylogenetic reviews for the role Picumnus genus.

During the past 100 years in densely populated south-eastern Brazil, wetlands have been severely transformed due to urbanization, agriculture and mining. The recently discovered São Paulo Marsh Antwren (Formicivora paludicola) is endemic to these wetlands, and is listed as "Critically Endangered" by the IUCN. The species is only found in an area of 1.42 km2, it has a sparse and fragmented distribution, low dispersal capacity, and has probably lost around 300 km2 of habitat in the past 100 years. Furthermore, very little is known about F. paludicola natural history, and so it is difficult to construct a robust conservation plan. Using Kernel home range estimations and the Adjusted-SD/Torus Shift test (a novel tool for animal-habitat association studies), we showed that the species avoids patches of the alien invasive ginger lily (Hedychium coronarium). Given the high density of their population (3.6 mature individuals/ha), F. paludicola could thrive in relatively small areas of suitable wetlands protected from human occupation and water contamination, however special attention should be paid to biological invasions, which may represent a serious threat to the remaining populations. Protecting a few small wetlands used by F. paludicola would be an important step towards general conservation and restoration of Atlantic Forest wetlands and its endemic endangered species.

Over the last 200 years the wetlands of the Upper Tietê and Upper Paraíba do Sul basins, in the southeastern Atlantic Forest, Brazil, have been almost-completely transformed by urbanization, agriculture and mining. Endemic to these river basins, the São Paulo Marsh Antwren (Formicivora paludicola) survived these impacts, but remained unknown to science until its discovery in 2005. Its population status was cause for immediate concern. In order to understand the factors imperiling the species, and provide guidelines for its conservation, we investigated both the species' distribution and the distribution of areas of suitable habitat using a multiscale approach encompassing species distribution modeling, fieldwork surveys and occupancy models. Of six species distribution models methods used (Generalized Linear Models, Generalized Additive Models, Multivariate Adaptive Regression Splines, Classification Tree Analysis, Artificial Neural Networks and Random Forest), Random Forest showed the best fit and was utilized to guide field validation. After surveying 59 sites, our results indicated that Formicivora paludicola occurred in only 13 sites, having narrow habitat specificity, and restricted habitat availability. Additionally, historic maps, distribution models and satellite imagery showed that human occupation has resulted in a loss of more than 346 km2 of suitable habitat for this species since the early twentieth century, so that it now only occupies a severely fragmented area (area of occupancy) of 1.42 km2, and it should be considered Critically Endangered according to IUCN criteria. Furthermore, averaged occupancy models showed that marshes with lower cattail (Typha dominguensis) densities have higher probabilities of being occupied. Thus, these areas should be prioritized in future conservation efforts to protect the species, and to restore a portion of Atlantic Forest wetlands, in times of unprecedented regional water supply problems.