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PREMISE: Primates are important seed dispersers, especially for large-seeded (>1 cm long) tropical species in continuous and fragmented rainforests. METHODS: In three forest fragments within the Montes Azules Biosphere Reserve, southern Mexico, we investigated the effect of seed passage through the gut of howler monkeys (Alouatta pigra) on the germination rate and maximum germination (%) of native, large-seeded species. One group of howler monkeys, per fragment, was followed and fresh feces collected. Large seeds were removed to compare their germination success with non-ingested seeds of the same species collected underneath parent plants. RESULTS: Feces contained large seeds from seven tree species (Ampelocera hottlei, Castilla elastica, Dialium guianense, Garcinia intermedia, Pourouma bicolor, Spondias mombin, Trophis racemosa) and one liana species (Abuta panamensis). Except for G. intermedia, ingested seeds germinated significantly faster than non-ingested seeds, which had negligible germination. Ingested seeds of D. guianense, P. bicolor, S. mombin, T. racemosa, and A. panamensis had significantly greater germination, while G. intermedia had significantly lower germination and seed ingestion had no apparent effect for A. hottlei and C. elastica. CONCLUSIONS: In general, seed ingestion by howler monkeys confers faster germination compared with non-ingested seeds. Faster germination reduces predation probabilities and increases seedling establishment in forest fragments. Primate dispersal services contribute to germination heterogeneity within plant populations of old-growth forest species and to their persistence in forest fragments.

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The data set provided here includes 8,320 frugivory interactions (records of pairwise interactions between plant and frugivore species) reported for the Atlantic Forest. The data set includes interactions between 331 vertebrate species (232 birds, 90 mammals, 5 fishes, 1 amphibian, and 3 reptiles) and 788 plant species. We also present information on traits directly related to the frugivory process (endozoochory), such as the size of fruits and seeds and the body mass and gape size of frugivores. Data were extracted from 166 published and unpublished sources spanning from 1961 to 2016. While this is probably the most comprehensive data set available for a tropical ecosystem, it is arguably taxonomically and geographically biased. The plant families better represented are Melastomataceae, Myrtaceae, Moraceae, Urticaceae, and Solanaceae. Myrsine coriacea, Alchornea glandulosa, Cecropia pachystachya, and Trema micrantha are the plant species with the most animal dispersers (83, 76, 76, and 74 species, respectively). Among the animal taxa, the highest number of interactions is reported for birds (3,883) followed by mammals (1,315). The woolly spider monkey or muriqui, Brachyteles arachnoides, and Rufous-bellied Thrush, Turdus rufiventris, are the frugivores with the most diverse fruit diets (137 and 121 plants species, respectively). The most important general patterns that we note are that larger seeded plant species (>12 mm) are mainly eaten by terrestrial mammals (rodents, ungulates, primates, and carnivores) and that birds are the main consumers of fruits with a high concentration of lipids. Our data set is geographically biased, with most interactions recorded for the southeast Atlantic Forest.

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Tropical forests are the global cornerstone of biological diversity, and store 55% of the forest carbon stock globally, yet sustained provisioning of these forest ecosystem services may be threatened by hunting-induced extinctions of plant-animal mutualisms that maintain long-term forest dynamics. Large-bodied Atelinae primates and tapirs in particular offer nonredundant seed-dispersal services for many large-seeded Neotropical tree species, which on average have higher wood density than smaller-seeded and wind-dispersed trees. We used field data and models to project the spatial impact of hunting on large primates by ∼ 1 million rural households throughout the Brazilian Amazon. We then used a unique baseline dataset on 2,345 1-ha tree plots arrayed across the Brazilian Amazon to model changes in aboveground forest biomass under different scenarios of hunting-induced large-bodied frugivore extirpation. We project that defaunation of the most harvest-sensitive species will lead to losses in aboveground biomass of between 2.5-5.8% on average, with some losses as high as 26.5-37.8%. These findings highlight an urgent need to manage the sustainability of game hunting in both protected and unprotected tropical forests, and place full biodiversity integrity, including populations of large frugivorous vertebrates, firmly in the agenda of reducing emissions from deforestation and forest degradation (REDD+) programs.

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Studies of the dispersal modes of plants aid our understanding of the dynamics of resource and its availability for dispersal agents. The present work sought to characterize the fruiting patterns of the native Caatinga (dryland) cactus Cereus jamacaru, identify its principal dispersers, and evaluate the effects of seed passage through digestive tract of dispersers on its germination. Cereus jamacaru present an annual fruiting pattern and fruiting peaks occurred during June/2009 and February/2010. A total of 135 visits by nine species of resident Caatinga bird species were recorded. The most frequent visiting bird species were Paroaria dominicana and Euphonia chlorotica. Length of bird visits varied from 15 seconds to 4 minutes and seeds removed by birds travelled 10.6 ± 11.2 m until dispersers make the first landing perch, in some cases more than 40 meters away. Germination tests show birds had a high quantity of viable seeds of C. jamacaru in its feces. Seeds that passed through the digestive tract of birds showed a similar germinability of the seeds of the control group. However, the seeds dispersed by birds showed lowest mean germination time related to the control group seeds. This study highlights the potential role of birds as seed dispersers of C. jamacaru, swallowing the whole seeds and defecating intact seeds, accelerating the germination process and transporting seeds away from the mother plant.

Estudos do modo de dispersão das espécies vegetais permitem o entendimento da dinâmica dos recursos e sua disponibilidade para os dispersores. O objetivo deste trabalho foi caracterizar o padrão de frutificação de Cereus jamacaru, uma espécie nativa da Caatinga, identificar os seus principais dispersores e avaliar o efeito da passagem das sementes pelo trato digestivo destes animais sobre sua germinação. Cereus jamacaru apresentou um padrão de frutificação anual, com pico de frutificação nos meses de Junho/2009 e Fevereiro/2010. No total foram registradas 135 visitas de nove espécies de aves frugívoras da Caatinga, sendo os dispersores mais frequentes Paroaria dominicana e Euphonia chlorotica. O tempo de duração das visitas foi curto, variando de 15 segundos a 4 minutos, e a distância média dos voos pós-alimentação foi 10,6 ± 11,2 m da planta-mãe, podendo também alcançar distâncias superiores a 40 metros. Os resultados dos testes de germinação mostraram que as aves apresentam uma alta quantidade de sementes viáveis de C. jamacaru em suas fezes. As sementes que passaram pelo trato digestivo das aves mostraram germinabilidade semelhante aquelas do grupo controle. No entanto, as sementes dispersadas pelas aves apresentaram um menor tempo médio necessário para germinação. Esse estudo destaca o papel das aves como potenciais dispersores de C. jamacaru, eliminando sementes intactas, acelerando o processo de germinação e carregando as sementes para longe da planta mãe.

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Studies of the dispersal modes of plants aid our understanding of the dynamics of resource and its availability for dispersal agents. The present work sought to characterize the fruiting patterns of the native Caatinga (dryland) cactus Cereus jamacaru, identify its principal dispersers, and evaluate the effects of seed passage through digestive tract of dispersers on its germination. Cereus jamacaru present an annual fruiting pattern and fruiting peaks occurred during June/2009 and February/2010. A total of 135 visits by nine species of resident Caatinga bird species were recorded. The most frequent visiting bird species were Paroaria dominicana and Euphonia chlorotica. Length of bird visits varied from 15 seconds to 4 minutes and seeds removed by birds travelled 10.6 ± 11.2 m until dispersers make the first landing perch, in some cases more than 40 meters away. Germination tests show birds had a high quantity of viable seeds of C. jamacaru in its feces. Seeds that passed through the digestive tract of birds showed a similar germinability of the seeds of the control group. However, the seeds dispersed by birds showed lowest mean germination time related to the control group seeds. This study highlights the potential role of birds as seed dispersers of C. jamacaru, swallowing the whole seeds and defecating intact seeds, accelerating the germination process and transporting seeds away from the mother plant.(AU)

Estudos do modo de dispersão das espécies vegetais permitem o entendimento da dinâmica dos recursos e sua disponibilidade para os dispersores. O objetivo deste trabalho foi caracterizar o padrão de frutificação de Cereus jamacaru, uma espécie nativa da Caatinga, identificar os seus principais dispersores e avaliar o efeito da passagem das sementes pelo trato digestivo destes animais sobre sua germinação. Cereus jamacaru apresentou um padrão de frutificação anual, com pico de frutificação nos meses de Junho/2009 e Fevereiro/2010. No total foram registradas 135 visitas de nove espécies de aves frugívoras da Caatinga, sendo os dispersores mais frequentes Paroaria dominicana e Euphonia chlorotica. O tempo de duração das visitas foi curto, variando de 15 segundos a 4 minutos, e a distância média dos voos pós-alimentação foi 10,6 ± 11,2 m da planta-mãe, podendo também alcançar distâncias superiores a 40 metros. Os resultados dos testes de germinação mostraram que as aves apresentam uma alta quantidade de sementes viáveis de C. jamacaru em suas fezes. As sementes que passaram pelo trato digestivo das aves mostraram germinabilidade semelhante aquelas do grupo controle. No entanto, as sementes dispersadas pelas aves apresentaram um menor tempo médio necessário para germinação. Esse estudo destaca o papel das aves como potenciais dispersores de C. jamacaru, eliminando sementes intactas, acelerando o processo de germinação e carregando as sementes para longe da planta mãe.(AU)

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Production of vertebrate-dispersed fruits is the most common strategy of tropical woody plants to disperse their seeds. Few studies have documented community-wide variation of fruit morphology and chemistry of vertebrate-dispersed fruits in species-rich tropical communities. We examined the functional diversity of fruit morphological and chemical traits of 186 species representing 57 plant families in an undisturbed lowland plant community in the Atlantic rain forest of SE, Brazil. We were particularly interested in associating morphological and chemical fruit traits to their main seed dispersers, either birds, mammals or 'mixed' (i.e. fruits eaten by birds and mammals). The morphological and chemical traits of fruits at the study site generally resemble the patterns observed in fruits worldwide. Bird fruits tend to be smaller than mammal fruits, being colored black or red, whereas mammal fruits are often yellow or green. Mammal fruits are more variable than bird fruits in relation to morphological traits, while the reverse is true for chemical traits. Mixed fruits resemble bird fruits in the patterns of variation of morphological and chemical traits, suggesting that they are primarily bird-dispersed fruits that are also exploited by mammals. Mixed fruits are common in tropical forests, and represent an excellent opportunity to contrast the effectiveness of different functional groups of frugivores dispersing the same plant species.

A produção de frutos carnosos é a estratégia mais comum adotada por plantas arbóreas tropicais para dispersar suas sementes. Poucos estudos têm documentado variações em nível de comunidade na morfologia e composição química de frutos carnosos em comunidades tropicais ricas em espécie. Nós examinamos a diversidade funcional das características morfológicas e químicas dos frutos de 186 espécies, representando 57 famílias de plantas em uma área de planície coberta por Mata Atlântica bem preservada no sudeste do Brasil. Estávamos particularmente interessados em associar as características morfológicas e químicas dos frutos a seus principais dispersores de sementes: aves, mamíferos ou "misto" (i.e. frutos consumidos por aves e mamíferos). As características morfológicas e químicas dos frutos no geral se assemelharam a padrões observados em outras partes do mundo. Frutos consumidos por aves tendem a ser menores do que os frutos de mamíferos, apresentando predominantemente cor preta ou vermelha, enquanto os frutos de mamíferos são geralmente amarelos ou verdes. Frutos consumidos por mamíferos são mais variáveis do que os frutos de aves em relação às características morfológicas, enquanto o inverso é verdadeiro para as características químicas. Frutos "mistos" assemelham-se aos frutos consumidos exclusivamente por aves em relação aos padrões de variação das características morfológicas e químicas, o que sugere serem eles frutos primariamente ornitocóricos que são também explorados por mamíferos. Frutos "mistos" são comuns em florestas tropicais e representam excelente oportunidade para contrastar a efetividade de diferentes grupos funcionais de frugívoros ao dispersar a mesma espécie de planta.

RESUMO

The behavior of foragers can directly affect the dispersal of seeds. Strangler figs are keystone resources throughout the tropics and are important resources for both primates and birds. We examined the foraging behavior of golden-handed tamarins and four bird species in a strangler fig to see how these behaviors might affect the dispersal of fig seeds. Tamarins removed fruit at a faster rate than did any of the bird species examined. Additionally, tamarins tended to swallow figs whole whereas birds tended to drop figs once they were processed. Tamarins visiting fig trees ingest large quantities of fig seeds that may be deposited throughout the forest. Birds on the other hand tended to slowly process fruits near the fig tree and drop processed fruit containing large quantities of seeds. Future studies need to be conducted to ascertain differences in post dispersal seed fate.

El comportamiento de foragers puede afectar directamente la dispersión de semillas. Los higos del estrangulador son recursos trapezoidales a través de las zonas tropicales y son recursos importantes para los primates y los pájaros. Examinamos el comportamiento del forraje de tamarins de oro-dados y cuatro especies del pájaro en un higo del estrangulador para ver cómo estos comportamientos pudieron afectar la dispersión de las semillas del higo. Fruta quitada Tamarins en una tarifa más rápida que la especie ua de los del pájaro examinada. Además, los tamarins tendieron para tragar los higos enteros mientras que los pájaros tendieron para caer los higos que fueron procesados una vez. Los árboles de higo de Tamarins que visitan injieren cantidades grandes de semillas del higo que se puedan depositar a través del bosque. Los pájaros por otra parte tendieron para procesar lentamente las frutas cerca del árbol de higo y la gota procesó la fruta que contenía cantidades grandes de semillas. Los estudios futuros necesitan ser conducidos para comprobar diferencias en sino de la semilla de la dispersión del poste.

RESUMO

The purpose of this study was to characterize the diet of the fish Brycon opalinus (Characidae) seasonally and locally, allowing for the determination of its food items and trophic relations with the aquatic and terrestrial environments. The study area encompasses three rivers (Paraibuna, Ipiranga and Grande) in the basin of the Paraibuna, southeast Brazil. Twelve monthly collections were made from January to December 2004. The degree of stomachic repletion and of accumulated visceral fat was analyzed, as was the intestinal length in each class of total length. The frequency of occurrence and the degree of food preference (DFP) of the food items of Brycon opalinus were determined by separating the vegetal and animal items, autochthonous and allochthonous, by insect order and vegetal family consumed. The frequency of occurrence of items of animal origin was found to be equivalent to that of vegetal origin, thus characterizing the omnivorism of Brycon opalinus feeding.

O objetivo foi caracterizar a dieta do peixe Brycon opalinus (Characidae) sazonalmente e localmente, sendo possível determinar os itens alimentares e as relações tróficas com os ambientes aquáticos e terrestres. A área de estudo abrange três rios (Paraibuna, Ipiranga e Grande) da bacia do Paraibuna, Sudeste do Brasil. Foram realizadas doze coletas mensais de janeiro a dezembro de 2004. O grau de repleção estomacal e o grau de acúmulo de gordura visceral foram analisados, assim como o comprimento intestinal em cada classe de comprimento total. A freqüência de ocorrência e o grau de preferência alimentar (GPA) dos itens alimentares de Brycon opalinus foram obtidos separando-se os itens vegetais e animais, autóctones e alóctones, por ordem de insetos e por família de vegetais consumidos. A freqüência de ocorrência dos itens de origem animal equivale à dos de origem vegetal, caracterizando assim a onivoria na alimentação de Brycon opalinus.

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RESUMO

The purpose of this study was to characterize the diet of the fish Brycon opalinus (Characidae) seasonally and locally, allowing for the determination of its food items and trophic relations with the aquatic and terrestrial environments. The study area encompasses three rivers (Paraibuna, Ipiranga and Grande) in the basin of the Paraibuna, southeast Brazil. Twelve monthly collections were made from January to December 2004. The degree of stomachic repletion and of accumulated visceral fat was analyzed, as was the intestinal length in each class of total length. The frequency of occurrence and the degree of food preference (DFP) of the food items of Brycon opalinus were determined by separating the vegetal and animal items, autochthonous and allochthonous, by insect order and vegetal family consumed. The frequency of occurrence of items of animal origin was found to be equivalent to that of vegetal origin, thus characterizing the omnivorism of Brycon opalinus feeding.

O objetivo foi caracterizar a dieta do peixe Brycon opalinus (Characidae) sazonalmente e localmente, sendo possível determinar os itens alimentares e as relações tróficas com os ambientes aquáticos e terrestres. A área de estudo abrange três rios (Paraibuna, Ipiranga e Grande) da bacia do Paraibuna, Sudeste do Brasil. Foram realizadas doze coletas mensais de janeiro a dezembro de 2004. O grau de repleção estomacal e o grau de acúmulo de gordura visceral foram analisados, assim como o comprimento intestinal em cada classe de comprimento total. A freqüência de ocorrência e o grau de preferência alimentar (GPA) dos itens alimentares de Brycon opalinus foram obtidos separando-se os itens vegetais e animais, autóctones e alóctones, por ordem de insetos e por família de vegetais consumidos. A freqüência de ocorrência dos itens de origem animal equivale à dos de origem vegetal, caracterizando assim a onivoria na alimentação de Brycon opalinus.