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In this study, we provide a genomic description of the first isolation of the Umattila virus (UMAV) in Brazil. The virus was obtained from the blood of a bird (Turdus fumigatus) and isolated in a C6/36 cell culture. The viral genome contains ten segments, and its organization is characteristic of viruses of the genus Orbivirus (family Sedoreoviridae). The coding region of each segment was sequenced, demonstrating the nucleotide identity with UMAV. The phylogenetic inference results were in line with these findings and demonstrated the formation of two distinct monophyletic clades containing strains isolated around the world, where our isolate, belonging to the same clade as the prototype strain, was allocated to a different subclade, highlighting the genetic divergence between them. This work reports the first isolation of UMAV in Brazil, and due to the scarcity of information on this viral agent in the scientific literature, it is essential to carry out further studies to better understand its epidemiology, dispersion, and, in particular, its interactions with vertebrate hosts, vectors, and the environment.

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The distribution of a species reflects its ecological adaptability and evolutionary history, which is shaped by the environment and represents a dynamic area subject to anthropogenic environmental change. We used the MaxEnt algorithm to construct ecological niche models for four thrush species within the Turdus genus; T. amaurochalinus, T. chiguanco, T. falcklandii and T. rufiventris. These models were used to predict the potential geographic distributions of these species that are expanding their ranges in South America. Using occurrence records, we estimated currently occupied areas for each species. We also identified suitable habitats and projected possible areas to be colonized by the four species at continental scale. Temperature annual range had the highest influence for T. falcklandii, while human modification was the main variable explaining the distribution of the other three species. The potential distribution area ranged from 2.5 million km2 for T. falcklandii to nearly seven million km2 for T. amaurochalinus. Large proportions of suitable area remain unoccupied by all four species, being 50% for T. amaurochalinus and T. rufiventris, and about 70% for T. chiguanco and T. falcklandii. Anthropogenic disturbances, such as habitat loss and ecosystem transformation, lead to non-random species extinction and biotic homogenization, highlighting the importance of predictive models as valuable tools for informing mitigation policies and conservation strategies. Thrushes are progressively expanding their ranges, and the colonization of new habitats could bring new challenges.

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Parasites play a pivotal role in ecosystem health, influencing human and zoonotic diseases, as well as biodiversity preservation. The genus Trypanosoma comprises approximately 500 species mostly found in wildlife animals. This study focuses on identifying trypanosomes found in the white-necked thrush (Turdus albicollis) and the yellow-legged thrush (Turdus flavipes) in the Neotropics. First, we demonstrate the utility of an 18S rDNA sequence-structure phylogeny as an alternative method for trypanosome classification, especially when gGAPDH sequences are unavailable. Subsequently, the sequence-structure phylogeny is employed to classify new trypanosome sequences discovered in wild birds, placing them within the Ornithotrypanum subgenus. This marks the first identification of Ornithotrypanum in Neotropical birds, contributing to the understanding of the distribution and ecological adaptation of avian trypanosomes. Beyond taxonomy, this study broadens our comprehension of the ecological implications of avian trypanosomes in the Neotropics, emphasizing the need for continued research in this field. These findings underscore the importance of alternative classification methods, which are essential to unravel the complex interactions between parasites, wildlife hosts, and their ecosystems.

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Urbanization is one of the more important phenomena affecting biodiversity in the Anthropocene. Some organisms can cope with urban challenges, and changes in birds' acoustic communication have been widely studied. Although changes in the timing of the daily organization of acoustic communication have been previously reported, there is a significant gap regarding possible variations in song structure between dawn and dusk choruses. Considering that urbanization imposes different soundscapes for dawn and dusk choruses, we postulate two hypotheses: (i) there are variations in song parameters between dawn and dusk choruses, and (ii) such parameters within the city will vary in response to urban noise. We studied urban and extra-urban populations of Chiguanco Thrush in La Paz, Bolivia, measuring in dawn and dusk choruses: song length; song sound pressure level; minimum, maximum, range and dominant frequency; and the number of songs per individual. The results support our two hypotheses: there were more songs, and songs were louder and had larger band widths at dawn than at dusk in urban and extra-urban populations. Urban Chiguanco Thrushes sing less, the frequency of the entire song rises, and the amplitude increases as compared with extra-urban Chiguanco Thrushes. Understanding variations between dawn and dusk choruses could allow for a better interpretation of how some bird species cope with urban challenges.

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Resumen Igual que es posible trazar una historia de los cantos de las aves, de su recepción por y su relación con los seres humanos, también se puede especular sobre si esos cantos pueden funcionar como historia, viva, sonora, en qué grado y modos, así como en qué diferiría esa historia aviar de la humana o si podría enriquecerla. Muchas aves, después de todo, transmiten y aprenden sus cantos unas de otras, construyen sobre ellos y los complican, recogiendo otros sonidos que asumen e incorporan, sonidos humanos incluidos. Crean así paisajes sonoros que no siempre quedan de fondo: en ocasiones, reclaman su relevancia y toman el primer plano, en la historia y como historia.

Abstract Just as it is possible to trace a history of the songs of birds, of their reception by human beings, and of how humans relate to them, it is also possible to speculate on whether these songs can function as history, a living, resounding history, to which degree and in which ways. As well as on how that avian story would differ from the human one, or if it could enrich it. Many birds, after all, learn their songs from each other, they build on and complicate them, picking up other sounds they incorporate, human sounds included. Thus, they create soundscapes that are not always in the background: sometimes, they claim their relevance and take the foreground, in history and as history.

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To elucidate the relationships and spatial range evolution across the world of the bird genus Turdus (Aves), we produced a large genomic dataset comprising ca 2 million nucleotides for ca 100 samples representing 53 species, including over 2000 loci. We estimated time-calibrated maximum-likelihood and multispecies coalescent phylogenies and carried out biogeographic analyses. Our results indicate that there have been considerably fewer trans-oceanic dispersals within the genus Turdus than previously suggested, such that the Palaearctic clade did not originate in America and the African clade was not involved in the colonization of the Americas. Instead, our findings suggest that dispersal from the Western Palaearctic via the Antilles to the Neotropics might have occurred in a single event, giving rise to the rich Neotropical diversity of Turdus observed today, with no reverse dispersals to the Palaearctic or Africa. Our large multilocus dataset, combined with dense species-level sampling and analysed under probabilistic methods, brings important insights into historical biogeography and systematics, even in a scenario of fast and spatially complex diversification.

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Abstract: According to the enemy release hypothesis (ERH) the spread of invasive species will be facilitated by release from their enemies as they occupy new areas. However, the ERH has rarely been tested by comparing populations of native (non-invasive, long established) species with expanding or shifting ranges, to the same species as invasive in another area. We tested the ERH with respect to blood parasite levels (prevalence and intensity of Plasmodium spp. and Haemoproteus spp.) of (a) two closely related, widely distributed species of thrush (Turdus leucomelas and T. merula), and (b) an invasive sparrow (Passer domesticus) whose range has expanded from the Old World to the New World since the 18th century. A total of 158 birds were sampled in Portugal and 99 in Brazil. All bird species were parasitized, and 55% of the individuals collected were parasitized, and the mean intensity of infection was of 28 parasites per 10,000 erythrocytes. We assessed whether differences in levels of infection (prevalence and intensity) were due to site (tropical/New World and temperate/Old World) or host species. The ERH was supported: Passer domesticus and Turdus merula had higher levels of parasitism in the Old World than in the New World. Thus, P. domesticus seems to be benefitting from its "recent" range expansion, compared to T. leucomelas, through ecological release from its native parasites and because the parasites of the recently invaded area seem to be infesting native species instead.

Resumo: De acordo com a hipótese da liberação do inimigo (HLI), a disseminação de espécies invasoras será facilitada pela liberação de seus inimigos ao ocuparem novas áreas. No entanto, a HLI raramente é testada comparando-se as populações de espécies nativas (não invasivas, estabelecidas há muito tempo) que apresentam expansão ou alteração de habitats, com populações das mesmas espécies em habitats que foram invadidos. Testamos a HLI com relação aos níveis de parasitas no sangue (prevalência e intensidade de Plasmodium spp. e Haemoproteus spp.). De (a) duas espécies estreitamente relacionadas e amplamente distribuídas de Turdus (Turdus leucomelas e T. merula), e (b) um pardal invasor (Passer domesticus) cujo alcance se expandiu do Velho Mundo para o Novo Mundo desde o século 18. Um total de 158 aves foram amostradas em Portugal e 99 no Brasil. Todas as espécies foram parasitadas e 55% dos indivíduos foram parasitados, sendo que a intensidade média da infecção foi de 28 parasitas por 10.000 eritrócitos. Avaliamos se as diferenças nos níveis de infecção (prevalência e intensidade) foram devidas ao local (tropical/Novo Mundo e temperado/Velho Mundo) ou espécies hospedeiras. A HLI foi corroborada: Passer domesticus e Turdus merula apresentaram valores mais elevados de parasitismo no Velho Mundo do que no Novo Mundo. Assim, P. domesticus parece estar se beneficiando de sua expansão "recente" em comparação com T. leucomelas, através da liberação ecológica de seus parasitas nativos porque os parasitas da área recentemente invadida parecem infestar espécies nativas.

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Phylogeographic studies seeking to describe biogeographic patterns, infer evolutionary processes, and revise species-level classification should properly characterize the distribution ranges of study species, and thoroughly sample genetic variation across taxa and geography. This is particularly necessary for widely distributed organisms occurring in complex landscapes, such as the Neotropical region. Here, we clarify the geographic range and revisit the phylogeography of the Black-billed Thrush (Turdus ignobilis), a common passerine bird from lowland tropical South America, whose evolutionary relationships and species limits were recently evaluated employing phylogeographic analyses based on partial knowledge of its distribution and incomplete sampling of populations. Our work employing mitochondrial and nuclear DNA sequences sampled all named subspecies and multiple populations across northern South America, and uncovered patterns not apparent in earlier work, including a biogeographic interplay between the Amazon and Orinoco basins and the occurrence of distinct lineages with seemingly different habitat affinities in regional sympatry in the Colombian Amazon. In addition, we found that previous inferences about the affinities and taxonomic status of Andean populations assumed to be allied to populations from the Pantepui region were incorrect, implying that inferred biogeographic and taxonomic scenarios need re-evaluation. We propose a new taxonomic treatment, which recognizes two distinct biological species in the group. Our findings illustrate the importance of sufficient taxon and geographic sampling to reconstruct evolutionary history and to evaluate species limits among Neotropical organisms. Considering the scope of the questions asked, advances in Neotropical phylogeography will often require substantial cross-country scientific collaboration.

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Among known bird species, oscines are one of the few groups that produce complex vocalizations due to vocal learning. One of the most conspicuous oscine passerines in southeastern South America is the Rufous-bellied Thrush, Turdus rufiventris. The complete mitochondrial genome of this species was sequenced with the Illumina HiSeq platform (Illumina Inc., San Diego, CA), assembled using MITObim software and annotated by MITOS web server and Artemis software. This mitogenome contained 16 669 bases, organized as 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and a control region (d-loop). The sequencing of the Rufous-bellied Thrush mitochondrial genome is of particular interest for better understanding of population genetics and phylogeography of the Turdidae family.

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Turdus ignobilis is a widely distributed thrush species throughout northern South America and the Amazon, inhabiting a diverse set of habitats ranging from floodplain forests, white sand "campinas", to highland forests (Andes and Tepuis). There are currently six known subspecies of T. ignobilis, which vary extensively phenotypically and also ecologically, but whose interspecific limits and evolutionary history have never been investigated before. In this study, we used molecular data and plumage characters to review the taxonomy and uncover the evolutionary relationships of the six T. ignobilis subspecies described to date. We estimated gene and species trees based on both mitochondrial (ND2 and COI) and nuclear (TGFB2 and G3PDH) genes, which recovered, with high statistical support, the polyphyly of Turdus ignobilis, as currently defined. Therefore, based on our results, we propose a new taxonomic treatment that splits T. ignobilis into at least three separate species based on both molecular data and plumage characters. Each newly recognized species inhabit a distinct habitat type, with "true" T. ignobilis occurring in highland habitats of the Tepuis and the Andes, while T. arthuri and T. debilis are tied to "white-sand forest" and várzea floodplain forests in lowland Amazonia, respectively.

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Lead is a commonly monitored heavy metal because of potential health effects on exposed organisms. We quantified lead in secondary feathers of two passerine bird species, clay-colored thrushes (Turdus grayi) and great-tailed grackles (Quiscalus mexicanus), from an urban and a rural site in the municipality of Merida, Yucatan. Urban lead concentration was significantly higher than its rural counterpart for both species (p < 0.05). In the urban site, lead concentration was similar in both species (p = 0.14). However, data from the rural site showed that lead concentration was significantly higher in thrush feathers (p < 0.05). Lead levels herein presented are among the lowest ever reported suggesting that either lead accumulation or absorption is limited. Finally, our data seem to support the hypothesis that species feeding ecology plays a major role in lead accumulation.

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Fruits of trumpet tree (Cecropia spp.) attract different species of birds and mammals. Boas (Boa constrictor) are sit-and-wait strategists, able to choose to ambush in microhabitats that are frequently visited by prey. We have seen two events of predation of passerines (Pitangus sulphuratus, Turdus rufiventris) by boas on the same trumpet tree (Cecropia pachystachya) in a remnant of Cerrado, in the city of Campo Grande/MS. These reports may be evidence of strategic association of boas to trumpet trees, considering the density of snakes recorded on the tree and the constant visits by potential prey during fruiting periods. Besides encouraging a more detailed investigation on the strategies of predation by boas, our records constitute relevant information about the snake natural history.

Frutos de embaúba (Cecropia spp.) atraem diversas espécies de aves e mamíferos. Jiboias (Boa constrictor) são estrategistas senta-espera, capazes de selecionar micro-habitats que são frequentemente visitados por presas. Nós presenciamos dois eventos de predação de passeriformes (Pitangus sulphuratus, Turdus rufiventris) por jiboias sobre uma mesma embaúba (Cecropia pachystachya) em um remanescente de Cerrado, localizado na cidade de Campo Grande/MS. Esses relatos podem ser indícios de associações estratégicas das jiboias ès embaúbas, considerando a densidade de serpentes na árvore e a constante visitação de presas potenciais durante os períodos de frutificação. Além de estimular uma investigação mais detalhada sobre as estratégias de predação das jiboias, esses registros constituem informações relevantes sobre sua história natural.

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Synthesis studies are essential for detecting subjects that have not yet been fully explored. Therefore, a scientiometric study was conducted in order to evaluate the state of knowledge about the Turdidae bird family in Brazil. Searches were performed using the software Publish or Perish©. We found 23 papers from the period January 1990 to August 2012 directly involving the bioecological study of thrushes. Some studies were carried out on more than one species, giving a further 31 papers in which taxa of the Turdidae family were included. Using the dominance index, Turdus albicollis, T. amaurochalinus, T. leucomelas and T. rufiventris were considered eudominants. There was a greater frequency of studies based on T. leucomelas (χ ² c. (11.07) = 15.55, df = 5, P < 0.05). Turdus subalaris and Catharus ustulatus have also been studied and found to be subdominant. It was possible to define seven categories as areas of knowledge. From the spatial distribution of the localities (biomes) sampled by studies involving thrushes it was inferred that the most studied species are those having a greater distribution in Brazil. Finally, species naturally more restricted to northern Brazil have been less studied, mainly because most studies involving thrushes have been performed in southern and southeastern Brazil, mainly in the Atlantic Forest and Cerrado biomes.

Trabalhos de síntese são fundamentais para a detecção de campos ainda pouco explorados na ciência. Neste sentido, foi efetuado um estudo cienciométrico avaliando o estado de conhecimento da família de aves Turdidae no Brasil. Foram efetuadas buscas de trabalhos desenvolvidos no Brasil sobre sabiás, para tais buscas foi utilizado o Software Publish or Perish© no recorte temporal de janeiro de 1990 até agosto de 2012. Foram encontrados 23 artigos envolvendo diretamente o estudo bioecológico de sabiás. Alguns destes, efetuados abordando mais de uma espécie, totalizando 31 vezes em que os táxons da família foram contemplados. Através do índice de dominância, Turdus albicollis, T. amaurochalinus, T. leucomelas, e T. rufiventris foram consideradas eudominantes. Houve maior frequência de estudo de T. leucomelas (χ² c. (11,07) = 15,55, gl = 5, P < 0,05). Turdus subalaris e Catharus ustulatus também foram contempladas e consideradas subdominantes. Foi possível definir sete categorias considerando as áreas de conhecimento. É possível inferir através da espacialização dos locais (biomas) amostrados pelos estudos envolvendo turdídeos, que as espécies mais estudadas são também as que possuem maior distribuição no Brasil. Finalmente, espécies com distribuição restrita ao norte brasileiro foram pouco estudadas, devido principalmente, ao fato que a maioria dos estudos envolvendo turdídeos estão concentrados na região Sul e Sudeste do Brasil, desenvolvidos principalmente nos biomas Mata Atlântica e Cerrado.

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Seasonal segregation among syntopic species can be viewed as one of the available strategies for coexistence, reducing competitive process. The present work therefore aimed to interpret the assemblage structures comprising birds of the genus Turdus (Turdidae), through the analysis of seasonal variation in the species occurrence in a forest remnant located in the southcenter State of Paraná. Mist-netting was employed twice a month for capturing birds, totalling an annual effort of 7488 h.m². The frequency of occurrence, constancy and class of species dominance was determined, together with the parameters generally used in studies of ecological communities (richness, abundance, diversity and evenness). A total of 162 individuals were captured, representing five species. Turdus rufiventris was the most constant and frequent species. Turdus amaurochalinus and Turdus leucomelas were captured with variable constancies and frequencies along the seasons. Turdus amaurochalinus was also very common and may present an overlapping process between migrant and non-migrant individuals during spring. Turdus albicolis was considered accessory, whereas Turdus subalaris was only registered during the reproductive period. Hence, it was possible to observe that seasonal modifications occurred both in the frequency of occurrence and in the constancy and dominance of species. These results indicated the possibility of a lower use of the environment during the breeding season, as well as the presence of a higher number of individuals in summer and increased abundance of Turdus rufiventris and T. leucomelas during autumn and winter.

Segregações sazonais entre espécies sintópicas podem ser interpretadas como táticas utilizadas para a coexistência, diminuindo processos competitivos. Neste contexto, o presente trabalho buscou interpretar a estrutura da assembléia formada por aves do gênero Turdus (Turdidae) para averiguar a possibilidade de padrões distintos de ocorrência em função da variação sazonal em um fragmento florestal situado no Centro-sul do Estado do Paraná. Foram utilizadas redes ornitológicas para a captura das aves, com um esforço amostral anual de 7488 h.m². Por meio das capturas quinzenais foi possível a obtenção do índice de frequência de ocorrência, constância e classes de dominância das espécies, bem como, de parâmetros ecológicos utilizados em estudos de comunidades. Um total de 162 indivíduos pertencentes a cinco espécies foram capturados. Turdus rufiventris foi a espécie mais frequente e constante durante o estudo. Turdus amaurochalinus e T. leucomelas foram capturadas com frequências e constâncias variáveis entre as estações do ano, sendo que, para T. amaurochalinus houve evidências de sobreposição de populações migrantes e não migrantes durante a primavera. Turdus albicollis foi considerada acessória, enquanto T. subalaris foi registrada somente durante a temporada reprodutiva. Desta forma, foi possível observar que ocorrem modificações sazonais, tanto na frequência de ocorrência, quanto na constância e dominância das espécies. Tais resultados indicam a possibilidade de menor intensidade do uso do ambiente durante o período reprodutivo, assim como a presença de um maior número de espécies no verão e aumento da abundância de T. rufiventris e T. leucomelas durante o outono e inverno.

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Sex determination is important for conservation and population studies, particularly for reproduction programs of threatened species and behavioural ecology. Turdus amaurochalinus, Creamy-bellied Thrush, only exhibits sexual dimorphism during the breeding season, when males are considered to show intense yellow bills, and females and immature males show dark brown bills. The objectives of this study were: 1) to determine the sex of individuals using genetic techniques, and 2) to test the hypothesis that sex dimorphism can be detected by morphometry. This study was carried out at Parque Nacional da Restinga de Jurubatiba, a preserved area located on the North coast of Rio de Janeiro State. The birds were captured using ornithological nets, singly marked with metal rings, weighed, measured and had blood samples collected before being released. The sex of 42 T. amaurochalinus individuals was determined using the CHD gene marker. A total of 20 males and 22 females were identified from June to August, with peak capture frequency in June. Turdus amaurochalinus females and males differed significantly in morphometrical measures. The most important traits to distinguish males from females were wing length (Student t-test=4.34, df=40, p=0.0001) and weight (Student t-test=2.08,df=40, p=0.044): females were heavier and had significantly shorter wing length than males. Females and males were correctly classified in 86% and 75% of cases, respectively, using Discriminant Analysis. The molecular analysis was the most secure method for sex determination in the studied species. Rev. Biol. Trop. 59 (2): 789- 794. Epub 2011 June 01.

La determinación del sexo es importante para la conservación y los estudios poblacionales. Turdus amaurochalinus no presenta aparente dimorfismo sexual. El objetivo de este estudio fue determinar el sexo a través de una técnica genética, mediante el uso del marcador del gen CHD y se puso a prueba la hipótesis de que el dimorfismo sexual puede ser detectado por morfometría. Este estudio se llevó a cabo en el Parque Nacional da Restinga de Jurubatiba, una zona protegida situada en la costa norte de Río de Janeiro. Las aves fueron capturadas con redes de niebla, los individuos se marcaron con anillos de metal, se pesaron, medieron y se les tomó una muestra de sangre antes de ser liberados. Un total de 20 machos y 22 hembras fueron identificados en el área de estudio desde junio hasta agosto, con la frecuencia máxima de captura en junio. La prueba de t-student fue usada para evaluar si hembras y machos se diferencian considerablemente en relación a medidas morfométricas. Los rasgos más importantes para distinguir machos de hembras fueron la longitud del ala y el peso: las hembras eran más pesadas y tenían longitud de ala considerablemente más corta que los machos. Hembras y machos fueron correctamente clasificados en un 86% y 75% de casos respectivamente, donde se usó un análisis discriminante. El análisis molecular es el método más seguro para la determinación sexual en la especie estudiada.

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We carried out a seed germination experiment using two thrush species in captivity. We compared the number of germinated seeds and germination time of control seeds (manually removed from fruits) and ingested seeds of Miconia prasina by two bird species, Turdus albicollis and T. amaurochalinus, and also compared retention times of seeds by both thrush species. Control seeds germinated more frequently than those ingested for one species, T. albicollis. The germination time of ingested seeds by T. amaurochalinus was similar to the control seeds but seeds ingested by T. albicollis took longer to germinate than the controls. Both thrush species had a similar seed defecation pattern. The cumulative number of defecated seeds increased by 2 hours after fruit ingestion. At the end of the first 30 minutes both species had already defecated approximately 50 percent of the seeds ingested Our results suggest that both species could act as disperser agents of M. prasina.

Realizamos um experimento de germinação utilizando duas espécies de Turdus em cativeiro. Comparamos o número de sementes germinadas e o tempo de germinação entre sementes controle (manualmente removidas dos frutos) e ingeridas de Miconia prasina por duas espécies de aves, Turdus albicollis e T. amaurochalinus, e também comparamos o tempo de retenção das sementes pelas duas espécies de Turdus. Sementes controle germinaram com maior freqüência do que as ingeridas por uma das espécies, T. albicollis. O tempo de germinação das sementes ingeridas por T. amaurochalinus foi semelhante ao das sementes controle, mas as sementes ingeridas por T. albicollis demoraram mais para germinar do que as sementes controle. Ambas as espécies de Turdus tiveram um padrão similar de defecação das sementes. O número acumulado de sementes defecadas aumentou por 2 horas após a ingestão dos frutos. Ao final dos primeiros 30 minutos ambas espécies já haviam defecado aproximadamente 50 por cento das sementes ingeridas Nossos resultados sugerem que as duas espécies de aves podem atuar como agentes dispersores de sementes de M. prasina.

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Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis)...

Las restingas se consideran hábitats estresantes asociados al bosque del Atlántico brasileño y sus ecológicas se conocen poco. El objetivo principal del presente trabajo fue determinar el papel potencial de las aves frugívoras como dispersores de plantas en un hábitat de restinga. La información se recolectó en el Parque Nacional da Restinga de Jurubatiba, Brasil. Las aves se capturaron con redes de niebla y sus muestras fecales y de regurgitación se inspeccionaron en busca de semillas. Estudiamos seis especies de plantas de estas muestras. En general, el efecto del paso por el sistema digestivo de las aves sobre el porcentaje de germinación fue nulo (y negativo en la velocidad de germinación). Todas las especies de plantas estudiadas son numéricamente importantes a la comunidad y algunas de ellas tienen papeles principales en la sucesión de parches de vegetación. Entre las aves, Mimus gilvus es una especie residente importante, endémica de tales hábitats en Brasil, mientras que Turdus amaurochalinus es una especie visitante y puede ser importante para las plantas que fructifican durante su paso por el sitio del estudio. El efecto general de los pájaros en la dispersión de semillas en la restinga es probablemente positivo.

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RESUMO

We carried out a seed germination experiment using two thrush species in captivity. We compared the number of germinated seeds and germination time of control seeds (manually removed from fruits) and ingested seeds of Miconia prasina by two bird species, Turdus albicollis and T. amaurochalinus, and also compared retention times of seeds by both thrush species. Control seeds germinated more frequently than those ingested for one species, T. albicollis. The germination time of ingested seeds by T. amaurochalinus was similar to the control seeds but seeds ingested by T. albicollis took longer to germinate than the controls. Both thrush species had a similar seed defecation pattern. The cumulative number of defecated seeds increased by 2 hours after fruit ingestion. At the end of the first 30 minutes both species had already defecated approximately 50% of the seeds ingested Our results suggest that both species could act as disperser agents of M. prasina.

Realizamos um experimento de germinação utilizando duas espécies de Turdus em cativeiro. Comparamos o número de sementes germinadas e o tempo de germinação entre sementes controle (manualmente removidas dos frutos) e ingeridas de Miconia prasina por duas espécies de aves, Turdus albicollis e T. amaurochalinus, e também comparamos o tempo de retenção das sementes pelas duas espécies de Turdus. Sementes controle germinaram com maior freqüência do que as ingeridas por uma das espécies, T. albicollis. O tempo de germinação das sementes ingeridas por T. amaurochalinus foi semelhante ao das sementes controle, mas as sementes ingeridas por T. albicollis demoraram mais para germinar do que as sementes controle. Ambas as espécies de Turdus tiveram um padrão similar de defecação das sementes. O número acumulado de sementes defecadas aumentou por 2 horas após a ingestão dos frutos. Ao final dos primeiros 30 minutos ambas espécies já haviam defecado aproximadamente 50% das sementes ingeridas Nossos resultados sugerem que as duas espécies de aves podem atuar como agentes dispersores de sementes de M. prasina.