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1.
Parasitol Res ; 122(8): 1851-1861, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37233818

RESUMO

The high diversity of bats in the Neotropics is primarily associated with various ectoparasite species on their bodies. Interactions between these animals need to be comprehensively investigated at landscape scales, focusing on understanding the patterns of diversity of species. We sought to evaluate, througt bat captures and ectoparasite sampling, the determinants of the composition of ectoparasitic flies species present in bats in in the Amazon and Cerrado biomes and ecotone areas. We used a generalized dissimilarity model (GDM) to verify what factors explained the composition of ectoparasitic flies of bats using landscape metrics, geographic distance, biome, and host composition. Twenty-four bat species haboured a total of 33 species of ectoparasitic flies. Host composition was the best predictor of fly composition, followed by the environmental variables and by biome. Geographical distance presented negligible effects. Studies on large scales tend to reveal a wide diversity of ectoparasitic flies. Host composition, as the best predictor of fly composition, may be associated with interspecific characteristics among species. We recommend studies focusing on the landscape to understand better the parasitic associations of bats and their distribution across environments.


Assuntos
Quirópteros , Dípteros , Ectoparasitoses , Animais , Quirópteros/parasitologia , Ectoparasitoses/veterinária , Ectoparasitoses/parasitologia , Interações Hospedeiro-Parasita , Ecossistema
2.
Transbound Emerg Dis ; 69(4): 1770-1781, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33993650

RESUMO

The Amazon rainforest is considered the largest reservoir of culicids and arboviruses in the world. It has been under intense human-driven alteration, especially in the so-called 'Arc of Deforestation', located in the eastern and southern regions. The emergence and transmission of infectious diseases are increasing, potentially due to land-use change. We used landscape-scale mosquito surveillance across a forest fragmentation gradient in the southern Amazon to evaluate the relationship between forest disturbance and the composition and structure of mosquito communities with a particular focus on the potential for arbovirus emergence in the region. Generalized linear models and logistic regression were used to associate the degree of landscape disturbance with arbovirus vectors' richness and abundance. A total of 1,960 culicids, belonging to 50 species, were collected from 2015 to 2016. Among these species, 20 have been associated with the transmission of arboviruses. Our results show an association of land use, more specifically small size of forest remnants with more irregular shape and higher edge density, with the increase of arbovirus vectors' richness and abundance. Six species of mosquito vectors exhibited a higher probability of occurrence in landscapes with medium or high degrees of disturbance. Our results indicate that land-use change influences mosquito communities with potential implications for the emergence of arboviruses.


Assuntos
Arbovírus , Culicidae , Animais , Biodiversidade , Brasil/epidemiologia , Humanos , Mosquitos Vetores
3.
Mol Ecol Resour ; 22(3): 962-977, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34601818

RESUMO

Metabarcoding of environmental DNA (eDNA) is now widely used to build diversity profiles from DNA that has been shed by species into the environment. There is substantial interest in the expansion of eDNA approaches for improved detection of terrestrial vertebrates using invertebrate-derived DNA (iDNA) in which hematophagous, sarcophagous, and coprophagous invertebrates sample vertebrate blood, carrion, or faeces. Here, we used metabarcoding and multiple iDNA samplers (carrion flies, sandflies, and mosquitos) collected from 39 forested sites in the southern Amazon to profile gamma and alpha diversity. Our main objectives were to (1) compare diversity found with iDNA to camera trapping, which is the conventional method of vertebrate diversity surveillance; and (2) compare each of the iDNA samplers to assess the effectiveness, efficiency, and potential biases associated with each sampler. In total, we collected and analysed 1759 carrion flies, 48,686 sandflies, and 4776 mosquitos. Carrion flies revealed the greatest total vertebrate species richness at the landscape level, despite the least amount of sampling effort and the fewest number of individuals captured for metabarcoding, followed by sandflies. Camera traps had the highest median species richness at the site-level but showed strong bias towards carnivore and ungulate species and missed much of the diversity described by iDNA methods. Mosquitos showed a strong feeding preference for humans as did sandflies for armadillos, thus presenting potential utility to further study related to host-vector interactions.


Assuntos
Código de Barras de DNA Taxonômico , Dípteros , Monitoramento Ambiental , Vertebrados , Animais , Biodiversidade , Culicidae , Código de Barras de DNA Taxonômico/métodos , Humanos , Psychodidae/genética , Vertebrados/genética
4.
Transbound Emerg Dis ; 67(3): 1045-1051, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31793244

RESUMO

In order to determine whether southern Amazonian bats could harbour hantaviruses we, serologically and molecularly, screened blood, saliva, excreta and organ tissues of 47 bats captured from September to December 2015. We found that only phyllostomid bats presented antibodies against hantavirus. The seropositive bats belonged to two species of Phyllostomid bats: the greater spear-nosed bat Phyllostomus hastatus (omnivorous) and the gnome fruit-eating bat Dermanura gnoma. The overall seroprevalence was of 4.2%. Therefore, we show here that hantaviruses are circulating among phyllostomid bats in the Amazonian arc of deforestation.


Assuntos
Anticorpos Antivirais/sangue , Quirópteros/virologia , Infecções por Hantavirus/veterinária , Orthohantavírus/imunologia , Animais , Brasil/epidemiologia , Quirópteros/imunologia , Monitoramento Epidemiológico , Feminino , Florestas , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Masculino , Estudos Soroepidemiológicos
5.
PeerJ ; 7: e7019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380146

RESUMO

Although the Atlantic Forest marmosets (Callithrix spp.) are among the best studied Neotropical primates, the Amazonian marmosets (Callibella humilis, Cebuella spp. and Mico spp.) are much less well-known. Even species diversity and distributions are yet to be properly determined because field data and materials currently available in scientific collections do not allow comprehensive taxonomic studies of Amazonian marmosets. From 2015 to 2018, we conducted 10 expeditions in key-areas within southern Amazonia where little or no information on marmosets was available. In one such region-the Tapajós-Jamanxim interfluve-we recorded marmosets with a distinctive pelage pigmentation pattern suggesting they could represent a new species. We tested this hypothesis using an integrative taxonomic framework that included phylogenomic data (ddRAD sequences), pelage pigmentation characters, and distribution records. We found that the marmosets of the northern Tapajós-Jamanxim interfluve have unique states in pelage pigmentation characters, form a clade (100% support) in our Bayesian and Maximum-Likelihood phylogenies, and occur in an area isolated from other taxa by rivers. The integration of these lines of evidence leads us to describe a new marmoset species in the genus Mico, named after the Munduruku Amerindians of the Tapajós-Jamanxim interfluve, southwest of Pará State, Brazil.

6.
Trans R Soc Trop Med Hyg ; 113(7): 424-427, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31050765

RESUMO

BACKGROUND: Arbovirus surveillance in field-collected mosquitoes is essential in monitoring virus activity to avoid emergence and outbreaks of arboviruses. METHODS: We used reverse transcription polymerase chain reaction methods to search for arbovirus in mosquitoes collected in Brazil's southeast Amazon forest remnants during 2015-2016. RESULTS: We detected Iheus virus (ILHV) RNA in Culex declarator, Culex (Melanoconion) and Ochlerotatus serratus mosquitoes. CONCLUSIONS: These results indicate ILHV circulation in the studied area, highlighting its potential emergence in human population. More studies are necessary to confirm the roles of these three species in ILHV maintenance.


Assuntos
Arbovírus/isolamento & purificação , Culicidae/virologia , Animais , Brasil , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Primates ; 58(3): 441-448, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28213677

RESUMO

Historical records of Ateles chamek (black-faced black spider monkey) suggest that the species range extends further south of the known species distribution, within an ecotonal region between the Amazonia, Cerrado and Pantanal biomes in Brazil. Ecotones are zones of habitat transition with high species richness that remain undersampled as conservationists often prioritize biodiversity hotspots. Thus, distribution ranges may be inaccurately measured when species occur in ecotonal zones. We report the first precise records of A. chamek in 24 new localities surveyed in the ecotonal zone of the Upper Paraguay River Basin, and we present subgroup encounter rates in the 11 largest patches (>70 ha) along 207 km of the line transects surveyed. The new records represent an expansion of the distribution of A. chamek approximately 200 km to the south, increasing the known extent of its occurrence by 10.8%. Local tributaries may not be barriers for spider monkeys, which are able to swim and cross slow-moving rivers. However, the dry forests of the Cerrado and the flooded areas of the Pantanal, formed by grassland and scarce trees, may be habitat barriers for A. chamek. The populations living in this ecotonal zone are relatively abundant (1.1-6.67 subgroup sightings/10 km) compared to the heavily hunted continuous forests of northern Amazonia. Furthermore, these values are similar to those for other Ateles spp. inhabiting forests with low or no hunting pressure. We highlight the need for specific conservation action to protect the spider monkeys living in these landscapes, which are threatened by agriculture expansion.


Assuntos
Atelinae , Ecossistema , Animais , Brasil , Paraguai , Rios
8.
Folia Primatol (Basel) ; 87(3): 123-140, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27553249

RESUMO

In the northern Atlantic Forest, hunting and habitat loss have eliminated most large mammals that disperse zoochoric fruits. Due to the decrease in populations of large seed dispersers, yellow-breasted capuchins (Sapajusxanthosternos) are currently one of the largest arboreal fruit-eating mammals in the region. During 26 months, we followed 14-25 capuchins aiming to (1) present data on their dietary ecology, (2) verify the conservation status of plants in the diet, and (3) determine distance and habitat of seed deposition based on gut retention time. Capuchins showed a preference for feeding in old secondary forests in spite of the greater availability of primary forests. They fed on 109 species of fruits (42.7% of feeding frequency) and swallowed 85 species of seeds (mean width: 0.73 ± 0.57 cm; mean length: 1.17 ± 0.83 cm). Capuchins consumed mostly oil palm and manilkara fruits. We observed long distances of seed deposition (median 300-360 m); 36.8-41.7% of these events occurred in a distinct habitat, and seeds of 12 late-stage trees swallowed in the primary forest were deposited in old secondary forests. S. xanthosternos has an important role in the first phase of seed dispersal (seed removal from the parent tree and seed deposition), particularly for 23 endemic and 3 endangered plants.


Assuntos
Cebinae/fisiologia , Comportamento Alimentar , Dispersão de Sementes/fisiologia , Animais , Brasil , Espécies em Perigo de Extinção , Florestas , Frutas , Sementes , Árvores
9.
Am J Primatol ; 78(9): 950-60, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27228143

RESUMO

The yellow-breasted capuchin monkey (Sapajus xanthosternos) is one of the seven Brazilian primates that are currently threatened with extinction. Although the species is known to be threatened by habitat loss, hunting, and illegal pet trade, few data exist on how these threats influence its long-term population persistence. We conducted population viability analyses (PVAs) to estimate minimum viable populations of S. xanthosternos under 10 threat scenarios (i.e., varying hunting pressure and varying number of infants captured for the pet trade) for five forest fragments with different estimated carrying capacities (K). We also estimated the minimum forest fragment size required to sustain viable populations living under the same 10 threat scenarios, based on critical numbers of K obtained in sensitivity tests, below which the population would be unviable. Our PVAs suggests that hunting has a higher impact on population viability in comparison to threats from the pet trade. Annual losses of adult and young females from hunting had the most detrimental effect on population persistence under all forest fragment sizes. Such hunting pressure is not sustainable for populations living in areas ≤3,460 ha, since these areas may not support populations of ≥84 individuals. The seven largest of the 13 protected areas currently harboring capuchins should be effective at maintaining viable populations in the long term even under the greatest threat scenarios we modeled. Other large forest patches, mainly in the western part of the species distribution, are recommended as priority areas for protection to increase the chances of capuchins' survival for the long term. In addition, forest fragments of ≤782.8 ha cannot maintain viable populations, even when there are no threats from hunting or from captures for the pet trade. Increased law enforcement is necessary to prevent the hunting and capture of capuchins, especially within larger forest fragments. Am. J. Primatol. 78:950-960, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Cebus , Florestas , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Feminino , Masculino , Dinâmica Populacional
10.
Biota Neotrop. (Online, Ed. ingl.) ; 16(1): https://www.scielo.br/j/bn/a/BfSLLTnQwvLPRStQYRgSQCr/?format=pdf&lang=en, Jan.-Mar. 2016.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1443003

RESUMO

Conflicts in conservation may arise if two or more threatened species are involved in preypredator interaction. Predators may have a profound effect on small prey populations, thus conservation actions must consider inter-specific interactions involving threatened species. Here we report nest predation events on a wild population of the Endangered red-billed curassow Crax blumenbachii Spix, 1825 by a group of the Critically Endangered yellow-breasted capuchin monkeys Sapajus xanthosternos Wied-Neuwied, 1820 in the Brazilian Atlantic Forest. This is the first study to report egg predation of an threatened gamebird by an threatened primate. We recommend that systematic conservation planning for these threatened species consider interactions, especially considering upcoming reintroduction programs indicated in the National Action Plans for these species conservation.


Conflitos em conservac¸a˜o podem ocorrer quando duas espe´cies ameac¸adas sa˜o envolvidas em interac¸o˜es presa-predador. Predadores podem ter um profundo efeito sobre pequenas populac¸o˜es de presas, portanto ac¸o˜es de conservac¸a˜o devem considerar estas interac¸o˜es interespeci´ficas envolvendo espe´cies ameac¸adas. Reportamos aqui a predac¸a˜o de ovos em uma populac¸a˜o selvagem de mutum-do-sudeste Crax blumenbachii Spix, 1825 por um grupo monitorado de primatas criticamente ameac¸ados, macaco-pregodo-peito-amarelo Sapajus xanthosternos Wied-Neuwied 1820 na Mata Atlaˆntica. Este e´ o primeiro estudo a reportar a predac¸a˜o de ovos de uma espe´cie ameac¸ada de ave cinege´tica por um primata tambe´m ameac¸ado de extinc¸a˜o. Recomendamos o planejamento conciliado de ac¸o˜es de conservac¸a˜o para ambas espe´cies ameac¸adas, especialmente por os futuros programas de reintroduc¸a˜o indicados para as respectivas espe´cies em seus Planos de Ac¸a˜o Nacionais para a Conservac¸a˜o de Espe´cies Ameac¸adas de Extinc¸a˜o.

11.
Acta amaz ; 45(2): 187-194, abr.-jun. 2015. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455247

RESUMO

The effectiveness of ecological researches on small mammals strongly depends on trapping techniques to survey communities and populations accurately. The main goal of this study was to assess the efficiency of three types of traps (Sherman, Tomahawk and Pitfall) to capture non-volant small mammals. We installed traps in 22 forest fragments in the southern Brazilian Amazonia. We captured 873 individuals belonging to 21 species; most of the individuals (N = 369) and species (N = 19) were trapped using Pitfalls, followed by Shermans (N = 271 individuals; N = 15 species) and Tomahawks (N = 233 individuals; N = 15 species). Pitfalls trapped a richer community subset of small mammals than the two other types of traps, and a more abundant community subset than Tomahawks. Proechimys sp. was the most abundant species trapped (N = 125) and Tomahawk was the most efficient type of trap to capture this species (N = 97 individuals). Neacomys spinosus and Marmosops bishopi were more trapped in Pitfalls (N = 92 and 100 individuals, respectively) than Shermans and Tomahawks. Monodelphis glirina was more trapped in Shermans and Pitfalls than Tomahawks. Species composition trapped using the three types of traps were distinct. Pitfalls captured a more distinct subset of the small mammal community than the two other live traps. We recommend the association of the three types of traps to reach a more comprehensive sampling of the community of small mammals. Thus, as stated by previous studies, we also recommend the complementary use of Shermans, Tomahawks and Pitfalls to account for a thorough sampling of the whole small mammal community in researches conducted in the tropical forests of Amazonia.


A eficácia das pesquisas ecológicas de comunidade de pequenos mamíferos depende fortemente do uso de técnicas adequadas nas capturas durante as amostragens. O principal objetivos deste estudo foi avaliar a eficiências de três tipos de armadilhas (Sherman, Tomahawk e Pitfall) para capturas de pequenos mamíferos não-voadores. Nós instalamos armadilhas em 22 fragmentos de floresta no sul da Amazonia Brasileira. Nós capturamos 873 indivíduos de 21 espécies, a maior parte dos indivíduos (N=369) e espécies (N=19) foram capturados usando pitfalls, seguidos de Shermans (N=271 indivíduos, N=15 espécies) e Tomahawks (N=233 indivíduos, N= 15 espécies). Pitfalls capturou a maior riqueza da comunidade de pequenos mamíferos quando comparada aos outros dois tipos de armadilhas, e uma maior abundancia que Tomahawk. Proechimys sp. foi a espécies mais abundante capturada (N=125) e Tomahawk foi o tipo de armadilha mais eficiente para a captura desta espécie (N=97 indivíduos). Neacomys spinosus e Marmosops bishopi foram mais capturados em Pitfalls (N = 92 e 100 indivíduos, respectivamente) que Shermans e Tomahawks. Monodelphis glirina foram mais capturados em Shermans e Pitfalls que Tomahawks. A composição de espécies capturada usando os três tipos de armadilhas foi distinta. Pitfalls capturou um diferente subgrupo da comunidade de pequenos mamíferos quando comparado aos outros dois tipos de live traps. Assim, como sugerido em estudos anteriores, nós também recomendamos o uso conjugado de Sherman, Tomahawks e Pitfalls para uma amostragem mais completa da comunidade de pequenos mamíferos em pesquisas realizadas nas florestas tropicais da Amazônia.


Assuntos
Animais , Biodiversidade , Caça/métodos , Mamíferos , Métodos , Biota
12.
Biota neotrop. (Online, Ed. port.) ; 13(2): 70-75, Apr-Jun/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-682392

RESUMO

The Brazilian Pantanal comprises a mosaic of forest and field environments harbouring a rich community of large and midsized mammals that are adapted to the annual hydrological cycle. Here we evaluated richness and composition of large and midsized mammals inhabiting forested and open habitats affected by yearly floods in the Pantanal in Cáceres from October 2009 to September 2010. We compared these communities in marshes, dry forests and riparian forests based on 640 camera-traps.nights, sights, tracks, faecal samples and interviews. We also compared results in a private land (Descalvados Farm) and in a protected area (Taiamã Ecological Station). In total, we sampled 26 large and midsized mammals, including five threatened and two near threatened species. Jaguars, collared peccaries and red-brocket deers were the only mammals recorded at all habitat types, while eleven species were recorded exclusively in one of the habitats. We identified a heterogeneous use of the habitat by the animal community surveyed in all three habitats during the wet and dry season. Furthermore, precipitation and river level affected the use of dry forests and marshes isolated from dry forests. Finally, 62% of large/midsized mammal species present in the surveyed region recorded outside the reserve; therefore, we recommend conservation actions to protect those species and also to preserve unprotected dry forests.


O Pantanal brasileiro é formado por um mosaico de ambientes florestados e campestres, abrigando uma rica comunidade de mamíferos de médio e grande porte adaptados ao ciclo hidrológico anual. Nós avaliamos a riqueza e composição de mamíferos de médio e grande porte em habitats florestados e campestres afetados pelas inundações anuais no Pantanal de Cáceres ente outubro/2009 e setembro/2010. Comparamos as comunidades em Campos Inundáveis, Matas Secas e Matas Ripárias com base em 640 armadilhas-fotográficas.noite, avistamentos, pegadas, amostras fecais e entrevistas. Nós também comparamos os resultados em uma área privada (Fazenda Descalvados) e em uma área protegida (Estação Ecológica Taiamã). No total, foram registradas 26 espécies de mamíferos de médio e grande porte, incluindo cinco espécies ameaçadas de extinção e duas quase ameaçadas. Onças-pintadas, catetos e veados-mateiro foram os únicos mamíferos registrados em todos os habitats, enquanto que 11 espécies foram registradas em apenas um tipo de hábitat. Identificamos diferença quanto ao uso dos habitats entre os três tipos de habitats durante a estação seca e chuvosa. Além disso, a precipitação e o nível do rio afetaram o uso da Mata Seca e Campos Inundáveis isolados das Matas Secas. Por fim, 62% das espécies foram registradas fora da reserva, por isso, recomendamos ações de conservação para proteger as espécies e também para preservar as florestas secas desprotegidas.

13.
Am J Primatol ; 71(5): 366-72, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19206141

RESUMO

Reports on use of stones as hammers and anvils to open hard nuts by wild capuchin monkeys are scarce and limited to Cebus libidinosus. Here, we report for the first time data on tool use-stones as hammer and anvils to open nuts-in wild C. xanthosternos and a description of new tool using sites for C. libidinosus. Our records were made by visiting anvil sites and by information obtained from local residents. We surveyed three different biomes: Caatinga (dry forest and thorn scrub), Cerrado (Brazilian bush savannah), and Atlantic forest (wet forest), all records of tool use were from Caatinga or transitional areas between habitats. The behavior is suggested to be routinely performed and widespread among several populations. The fruits of six plant species in different localities were opened with hammer stones by C. xanthosternos. Hammer stones were of similar weigh as those described in other studies of C. libidinosus. Conditions found in Caatinga, such as a more frequent use of the ground by the monkeys and/or food scarcity, may play an important role in the acquisition of nut-cracking behavior. The absence of more reports of nut cracking and other forms of tool use in other species of wild Cebus is likely to result from a lack of surveys in very dry and food-limited habitats or intrinsic characteristics of other Cebus species.


Assuntos
Cebus/psicologia , Comportamento de Utilização de Ferramentas , Animais , Brasil , Ecossistema , Humanos , Nozes
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