21 research outputs found

    Distribution of the assemblage of phlebotomine sandflies (Diptera: Psychodidae) along an environmental gradient.

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    The geographical distribution of leishmaniasis has undoubtedly expanded, and is now being reported to be in areas that were previously non-endemic. This study therefore aimed to investigate whether there is any variation in the structure and in the composition of phlebotomine communities along an environmental gradient - from a mesic to a xeric environment, across different climatic periods (rainy and dry seasons). Furthermore, we test whether there were differences in sex ratio of sand flies between wet and dry environments. A total of 535 specimens of sand flies belonging to 18 species were recorded. Richness, abundance, and composition of species were significatively higher in the xeric environment (semidecidual Forest) compared to the mesic environment (Riparina Forest). We unveiled site specific differences in sand fly collections since the community composition changes with the geographic distance among the sampling points. These results led to the conclusion that for sand flies species, the environmental conditions available for each species could be different within the habitat taking into account the degree of humidity in the forest as well as the climatic season (dry or wet). The present study gives a valuable contribution to the knowledge of sand flies, as a group of insects, from the Atlantic Forest biome

    Impact of resource availability on bee diversity.

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    Resource availability is an important predictor of abundance and species richness. In this paper we veri!ed why there is local variation in bee diversity testing the hypothesis that bee species richness and abundance will increase with increasing resource availability. Resource availability was considered here as the number of "owering plants and the number of plant species. Sampling was carried out at two sites in Brazil, the quartzitic range (Ouro Branco) and metaliferous !elds (Ouro Preto). At these sites ecosystems are endangered by high anthropogenic impacts, particularly due to mining and urbanization. #e samples were collected for 10 months in each site, twice a month, from 8:00 am to 5:00 pm. #e bees belonged to 77 species and 5 subfamilies. Bee species and abundance increased with the increase in the number of plant species and plant abundance at both sites. Bee richness and abundance were higher in Ouro Branco than in Ouro Preto. Our results showed that bee diversity may be regulated by resource availability

    Feeding behavior by hummingbirds (Aves: Trochilidae) in artificial food patches in an Atlantic Forest remnant in southeastern Brazil.

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    During flight, hummingbirds achieve the maximum aerobic metabolism rates within vertebrates. To meet such demands, these birds have to take in as much energy as possible, using strategies such as selecting the best food resources and adopting behaviors that allow the greatest energy gains. We tested whether hummingbirds choose sources that have higher sugar concentrations, and investigated their behaviors near and at food resources. The study was conducted at Atlantic forest remnant in Brazil, between June and December 2012. Four patches were provided with artificial feeders, containing sucrose solutions at concentrations of 5%, 15%, 25% and 35% weight/volume. Hummingbird behaviors were recorded using the ad libitum method with continuous recording of behaviors. The following species were observed: the Brazilian ruby Clytolaema rubricauda (Boddaert, 1783), Violet-capped woodnymph Thalurania glaucopis (Gmelin, 1788), Scale-throated hermit Phaethornis eurynome (Lesson, 1832), White-throated hummingbird Leucochloris albicollis (Vieillot, 1818), Versicoloured emerald Amazilia versicolor (Vieillot, 1818), Glittering-bellied emerald Chlorostilbon lucidus (Shaw, 1812) and other Phaethornis spp. C. rubricauda, P. eurynome and Phaethornis spp. visited the 35%-sucrose feeders more often, while the T. glaucopis visited the 25%-sucrose feeders more often. L. albicollis and A. versicolor visited more often solutions with sugar concentration of 15%. C. lucidus visited all patches equally. Three behavioral strategies were observed: 1) C. rubricauda and T. glaucopis exhibited interspecific and intraspecific dominance; 2) the remaining species exhibited subordinance to the dominant hummingbirds, and 3) P. eurynome and Phaethornis spp. adopted a hide-and-wait strategy to the dominant hummingbird species. The frequency of aggressive behaviors was correlated with the time the hummingbird spent feeding, and bird size. Our results showed that hummingbirds can adopt different strategies to enhance food acquisition; that more aggressive species feeding more than less aggressive species; and that the birds, especially if they were dominant species, visited high quality food resources more often

    Feeding behavior by hummingbirds (Aves: Trochilidae) in artificial food patches in an Atlantic Forest remnant in southeastern Brazil.

    Get PDF
    During flight, hummingbirds achieve the maximum aerobic metabolism rates within vertebrates. To meet such demands, these birds have to take in as much energy as possible, using strategies such as selecting the best food resources and adopting behaviors that allow the greatest energy gains. We tested whether hummingbirds choose sources that have higher sugar concentrations, and investigated their behaviors near and at food resources. The study was conducted at Atlantic forest remnant in Brazil, between June and December 2012. Four patches were provided with artificial feeders, containing sucrose solutions at concentrations of 5%, 15%, 25% and 35% weight/volume. Hummingbird behaviors were recorded using the ad libitum method with continuous recording of behaviors. The following species were observed: the Brazilian ruby Clytolaema rubricauda (Boddaert, 1783), Violet-capped woodnymph Thalurania glaucopis (Gmelin, 1788), Scale-throated hermit Phaethornis eurynome (Lesson, 1832), White-throated hummingbird Leucochloris albicollis (Vieillot, 1818), Versicoloured emerald Amazilia versicolor (Vieillot, 1818), Glittering-bellied emerald Chlorostilbon lucidus (Shaw, 1812) and other Phaethornis spp. C. rubricauda, P. eurynome and Phaethornis spp. visited the 35%-sucrose feeders more often, while the T. glaucopis visited the 25%-sucrose feeders more often. L. albicollis and A. versicolor visited more often solutions with sugar concentration of 15%. C. lucidus visited all patches equally. Three behavioral strategies were observed: 1) C. rubricauda and T. glaucopis exhibited interspecific and intraspecific dominance; 2) the remaining species exhibited subordinance to the dominant hummingbirds, and 3) P. eurynome and Phaethornis spp. adopted a hide-and-wait strategy to the dominant hummingbird species. The frequency of aggressive behaviors was correlated with the time the hummingbird spent feeding, and bird size. Our results showed that hummingbirds can adopt different strategies to enhance food acquisition; that more aggressive species feeding more than less aggressive species; and that the birds, especially if they were dominant species, visited high quality food resources more often

    Evaluation of matrix effect on the determination of rare earth elements and As, Bi, Cd, Pb, Se and In in honey and pollen of native Brazilian bees (Tetragonisca angustula ? Jata?) by Q-ICP-MS.

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    Bees are considered the main pollinators in natural and agricultural environments. Chemical elements from honey and pollen have been used for monitoring the environment, the health of bees and the quality of their products. Nevertheless, there are not many studies on honey and pollen of native Brazilian bees. The goal of this work was to determine important chemical elements (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Lu and Yb) along with As, Bi, Cd, Pb, Se and In, in honey and pollen of native Brazilian bees, assessing analytical interferences from the matrix. A proposed analytical method was developed for these elements by quadrupole ICP-MS. Matrix effect was verified in honey matrix in the quantification of As, Bi and Dy; and in pollen matrix for Bi, Cd, Ce, Gd, La, Pb and Sc. The quality of the method was considered satisfactory taking into consideration the recovery rate of each element in the spiked solutions: honey matrix (91.6?103.9%) and pollen matrix (94.1?115.6%). The quantification limits of the method ranged between 0.00041 and 10.3 ?g L?1 for honey and 0.00041?0.095 ?g L?1 for pollen. The results demonstrate that the method is accurate, precise and suitable

    Can pollination syndromes indicate ecologicalrestoration success in tropical forests?

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    We evaluated the pollination syndromes of plant species occurring in revegetated patches of riparian Atlantic Forest in orderto evaluate the success of restoration process. Between March 2013 and January 2014, the oral traits of all of the oweringplants found in, among four restoration sites of different ages and one reference site, were recorded and used to characterizepollination syndromes. Richness, abundance, and composition of pollination syndromes were related to season, age and widthof the forest fragment, species richness and abundance of sampled plants, and also to the quality of the surrounding matrix.There were differences in the composition of syndromes among sampling units and among seasons. Richness and abundanceof pollination syndromes varied among climatic periods, the highest values occurred at the end of the dry season and the startof the rainy season. Older, wider, and areas with more plants had higher values of richness and abundance of syndromes.The quality of the surrounding matrix inuences only the richness of syndromes. It was concluded that oral traits are goodindicators of ecological restoration of riparian forests and that the surrounding matrix contributes to the greater richness ofsyndromes. However, when planning for active restoration, attention should be given to the proper choice of plant species onthe basis of pollination syndromes that should attract pollinators

    Nest architecture, life cycle, and natural enemies of the neotropical leafcutting bee Megachile (Moureapis) maculata (Hymenoptera: Megachilidae) in a montane forest.

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    Studies on the nesting biology of cavity nesting hymenoptera (bees and wasps) have stimulated many questions related to the behavior, life cycle, trophic niche, and sex ratio to better understanding of the life history of insects. Leafcutting bees are common insects, and many are important and efficient pollinators of crops and other plants.We studied the nesting biology of Megachile (Moureapis ) maculata in a montane semi-deciduous forest in Brazil using trap nests in order to improve the knowledge of aspects of the natural history of this important pollinator group. During 27 months, 87 nests were collected with an average of seven brood cells per nest. Most of the nests were in cavities of 0.9 cm in diameter (77%), and the number of brood cells ranged from 1 to 11. Absence of seasonality in nesting behavior suggests a multivoltine species. The total mortality rate was 26%, with the cuckoo bee Coelyoxis (Acrocoelioxys ) sp. being the main natural enemy attacking 15% of brood cells. The sex ratio is clearly male-biased (1:0.42). Females and their brood cells were larger than males and their brood cells, which may suggest an imbalance in the energetic cost of each sex. The success of this bee species in colonizing trap nestsmakes it an interesting potential opportunity to use this species for pollination of cultivated Asteraceae plant species, like sunflower

    Prevalence and intensity of Streblidae in bats from a Neotropical savanna region in Brazil.

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    Bats of the family Phyllostomidae are common hosts to streblids known as bat flies. Here, we discuss the component community, prevalence and intensity of infection with species of Streblidae on an assemblage of phyllostomid bats in the Cafuringa Environmental Protection Area (APA Cafuringa) in the core area of the Cerrado in Central Brazil. A total of 1841 streblid individuals of 24 species occurred on 752 bats of 14 species. Ten species of streblids infected Glossophaga soricina (Pallas), whereas seven or fewer streblid species infected the other bat species. Nine bat fly species presented a prevalence of more than 50%, whereas some differences in the abundance of bat flies among hosts were observed. Strebla wiedemanni Kolenati, 1856 and Trichobius furmani Wenzel, 1966 were more host-specific compared to the other streblids, and they occurred in greater abundance on their preferred hosts. Trichobius uniformis Curran, 1935 and Strebla mirabilis (Waterhouse, 1879) were the least host-specific, occurring on five and six hosts, respectively

    Trap-nesting hymenoptera and their network with parasites in recovered riparian forests Brazil.

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    Different aspects of human activities can cause environmental change that endanger species persistence, alter species distributions, and lead to changes in antagonistic and mutualistic interactions, whereas deforestation and flooding of riparian forest results in landscapes consisting of patchily distributed riparian forest fragments in a matrix of pastures, plantations, and urban areas. Therefore, we assessed the richness, abundance, and trophic interactions of trap-nesting Hymenoptera and their parasites at four patches of restored riparian forest and at one reference natural fragment, of different sizes and ages, located at the Volta Grande Reservoir, in Minas Gerais and S?o Paulo states to answer the following questions: (1) Does the richness and abundance of cavity-nesting bees and wasps differ in riparian forest fragments according to the seasonal periods? (2) Does the composition of cavity-nesting bees and wasps vary among restoration and reference sites and between climate seasons (wet and dry)? (3) How do the degrees of specialization of the parasites vary among the patches of forest? We recorded 12 species of wasps, eight of bees, and nine species of parasites. Areas with longer time since restoration (reference site) showed higher species richness. However, the abundance was higher in most recent areas. The composition of bee and wasp assembly has not significantly changed between the climate seasons, although it is different between sampling areas. The richness and abundance were higher in warmer and rainy periods. The rate of bee and wasp mortality was high. The degree of specialization of parasites varies among sampling units, and the network of host-parasite interaction has a modular configuration with generalists and specialists. We concluded that the restored areas with more complex habitat could provide better conditions for the reestablishment of ecological interactions among these insects, the local flora, and other invertebrates, which together contribute to the success of the restored environments
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