23 research outputs found

    How Habitat Change and Rainfall Affect Dung Beetle Diversity in Caatinga, a Brazilian Semi-Arid Ecosystem

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    The aim of the present study was to evaluate how dung beetle communities respond to both environment and rainfall in the Caatinga, a semi-arid ecosystem in northeastern Brazil. The communities were sampled monthly from May 2006 to April 2007 using pitfall traps baited with human feces in two environments denominated “land use area” and “undisturbed area.” Abundance and species richness were compared between the two environments and two seasons (dry and wet season) using a generalized linear model with a Poisson error distribution. Diversity was compared between the two environments (land use area and undisturbed area) and seasons (dry and wet) using the Two-Way ANOVA test. Non-metric multidimensional scaling was performed on the resemblance matrix of Bray-Curtis distances (with 1000 random restarts) to determine whether disturbance affected the abundance and species composition of the dung beetle communities. Spearman's correlation coefficient was used to determine whether rainfall was correlated with abundance and species richness. A total of 1097 specimens belonging to 13 species were collected. The most abundant and frequent species was Dichotomius geminatus Arrow (Coleoptera: Scarabaeidae). The environment exerted an influence over abundance. Abundance and diversity were affected by season, with an increase in abundance at the beginning of the wet season. The correlation coefficient values were high and significant for abundance and species richness, which were both correlated to rainfall. In conclusion, the restriction of species to some environments demonstrates the need to preserve these areas in order to avoid possible local extinction. Therefore, in extremely seasonable environments, such as the Caatinga, seasonal variation strongly affects dung beetle communities

    The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

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    Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

    First report of Oxysternon silenus Castelnau (Scarabaeidae, Scarabaeinae, Phanaeini) in the Brazilian Atlantic Forest

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    First report of Oxysternon silenus Castelnau (Scarabaeidae, Scarabaeinae, Phanaeini) in the Brazilian Atlantic Forest. This is the first record of Oxysternon silenus in the Brazilian Atlantic Forest. Specimens were collected in the Serra Grande landscape, municipality of Ibateguara, in Alagoas State. The samples were done from August 17 to 19, 2007 with pitfall traps. Before the present study, Oxysternon silenus had been reported predominantly in Amazonian region. The finding of this species corroborates the hypothesis of the biogeographical relationships between the Amazon Rainforest and the Atlantic Forest.<br>Primeiro relato de Oxysternon silenus Castelnau (Scarabaeidae, Scarabaeinae, Phanaeini) na Mata Atlântica brasileira. Esse é o primeiro registro de Oxysternon silenus na Mata Atlântica brasileira. Os espécimes foram coletados em Serra Grande, município de Ibateguara, Alagoas. As coletas foram realizadas de 17 a 19 de agosto de 2007 com a utilização de armadilhas do tipo pitfall. Antes do presente estudo, Oxysternon silenus tinha sido reportada apenas na região Amazônica. O encontro dessa espécie reforça a hipótese das relações biogeográficas entre a Amazônia e a Mata Atlântica

    Recovery of dung beetle assemblages in regenerating Caatinga dry forests following slash-and-burn agriculture

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    Understanding patterns of tropical forest resilience is a central challenge in conservation ecology particularly in seasonally-dry tropical forests, where anthropogenic disturbance and climate change are pervasive threats. Here, we investigate the recovery rate and community organization of dung beetles along a Caatinga dry forest regeneration cline in the context of slash-and-burn agriculture in northeast Brazil. Assemblages were described considering a wide set of attributes, including abundance, taxonomic (Hill orders D0, D1 and D2) and functional diversity (functional richness, evenness and redundancy) and taxonomic/functional composition, across a chronosequence consisting of regenerating and old-growth forest stands exposed to different levels of aridity and chronic disturbance. In addition, we use body mass, diet, food relocation behaviour and habitat specificity of dung beetles as ecological attributes. Our results show that Caatinga dry forests supports dense but relatively impoverished dung beetle assemblages at both local and landscape scales, with the same small set of species dominating local assemblages. Dung beetles do not experience successional replacements along the regeneration gradient, with evidence of high resilience. Moreover, disturbance-associated dung beetle species (predominantly small-bodied generalists) resulted in assemblage convergence across the regeneration cline. Finally, chronic anthropogenic disturbance was a decisive driver of changes in abundance and taxonomic diversity, while aridity positively affected species composition and functional richness. These patterns resulted in the occurrence of spatially structured assemblages in response to a combination of both natural and anthropogenic variables, while under little or no influence of forest regeneration status across human-modified Caatinga landscapes. We conclude that the absence of directional changes in dung beetle assemblages through the forest succession pathway of regenerating second-growth forest is associated with the effect of aridity and human disturbances on community organization, including selection for certain species and functional groups, which in turn, can alter important ecological functions and consequently the resilience of dry forests

    Fruit-feeding Butterflies In Edge-dominated Habitats: Community Structure, Species Persistence And Cascade Effect

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    Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)As old-growth forests are converted into edge-affected habitats, a substantial proportion of tropical biodiversity is potentially threatened. Here, we examine a comprehensive set of community-level attributes of fruit-feeding butterfly assemblages inhabiting edge-affected habitats in a fragmented Atlantic forest landscape devoted to sugar cane production. We also explored whether the consequences of habitat loss and fragmentation can interact and cause cascading ecosystem changes, with the pervasive simplification of tree assemblages inhabiting edge-dominated habitats, altering fruit-feeding butterfly persistence. Butterflies were sampled in three forest habitats: small fragments, forest edges and patches of forest interior of a primary forest fragment. Assemblage attributes, including taxonomic composition, correlated to some patch (patch size) and landscape (such as forest cover) metrics as well as habitat structure (tree density and richness). Fruit-feeding butterfly assemblages in the forest interior differed from those in small fragments due to an increased abundance of edge-specialist species. On the other hand, several forest-dependent species were missing in both small fragments and forest edges. Our results suggest that edge-affected habitats dominated by pioneer tree species support taxonomically distinct assemblages, including the presence of disturbance-adapted species, and butterfly community structure is highly sensitive to fragmentation- and plant-related variables, such as forest cover and pioneer tree species. In this way, while the establishment of human-modified landscapes probably results in the local extirpation of forest-dependent species, it allows the persistence of disturbance-adapted species. Thus, forest-dependent species conservation and the plant-animal interaction webs they support could be improved by retaining a significant amount of core forest habitat.203539548'Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior' (CAPES) [02488/09-4]'Conselho Nacional de Desenvolvimento Cientifico e Tecnologico' (CNPq) [302574/2010-7, 304598/2011-9]'Programa de Pos Graduacao em Biologia Animal' (PPGBA-UFPE)Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE)CNPq [302585/2011-7, 303834/2015-3]CNPq (SISBIOTA-Brasil/CNPq) [563332/2010-7]FAPESP (BIOTA-FAPESP Program) [2011/50225-3, 2013/50297-0]National Science Foundation [DEB-1256742]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Winner–loser species replacements in human-modified landscapes

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    Community assembly arguably drives the provision of ecosystem services because they critically depend on which and how species coexist. We examine conspicuous cases of 'winner and loser' replacements (WLRs) in tropical forests to provide a framework integrating drivers, impacts on ecological organization, and reconfiguration of ecosystem service provisioning. Most WLRs involve native species and result from changes in resource availability rather than from altered competition among species. In this context, species dispersal is a powerful force controlling community (re)assembly. Furthermore, replacements imply a nearly complete functional reorganization of assemblages and new 'packages' of ecosystem services and disservices provided by winners. WLRs can thus elucidate the multiple transitions experienced by tropical forests, and have theoretical/applied implications, including the role that human-modified landscapes may play in global-scale sustainability

    What is the importance of open habitat in a predominantly closed forest area to the dung beetle (Coleoptera, Scarabaeinae) assemblage?

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    What is the importance of open habitat in a predominantly closed forest to the dung beetle assemblage? The Atlantic Forest in Brazil is one of the most highly disturbed ecosystems and is mainly represented by fragmented areas. However, in places where human disturbances have ceased, certain areas are showing a natural regeneration pattern. The aim of the present study was to determine how the dung beetle assemblage responds to distinct habitat structures in a fragment of Atlantic Forest. For such, open and closed forest areas were sampled in a fragment of the Atlantic Forest in the northeastern region of Brazil. Pitfall traps baited with excrement and carrion were used to collect the beetles. A total of 7,267 individuals belonging to 35 species were captured. Canthon chalybaeus and C. mutabilis were restricted to open areas. Nearly 90% of the individuals of C. aff. simulans and Deltochilum aff. irroratum were identified in these areas. A higher percentage (> 50%) of Canthon staigi, Dichotomius aff. depressicolis and D. aff. sericeus occurred in closed areas. Abundance differed between areas, with higher values in closed areas. Richness was not influenced by the habitat structure. NMDS ordination exhibited the segregation of areas and ANOSIM confirmed that this variable explained the assemblage of dung beetle species. The findings of the present study validate that open areas are associated to more restrictive conditions, limiting a higher abundance of dung beetle. Although situated near preserved fragments, the studied open areas increase the heterogeneity of the general landscape

    Attractivity of omnivore, carnivore and herbivore mammalian dung to Scarabaeinae (Coleoptera, Scarabaeidae) in a tropical Atlantic rainforest remnant Atratividade de Scarabaeinae (Coleoptera: Scarabaeidae) por fezes de mamíferos onívoros, carnívoros e herbívoros em um remanescente de Floresta Tropical Atlântica

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    In this study, performed in a remnant of Brazilian Atlantic Forest, three types of dung from animals with distinct alimentary habits were utilized, in order to verify possible differences of attractivity of these dungs to the Scarabaeinae and the influence of seasonality in the attractivity. Three habitats were sampled: edge, clearing and forest core, each with 40 pitfall traps. A total of 2,137 beetles were collected from August 2005 to July 2006. Canthidium sp. 1 (43%) and Dichotomius sericeus (41%) were the most abundant species. From the total number of beetles collected, 80.5% were attracted to human dung, 11% to jaguar dung, 7.8% to waterbuck dung and 0.7% to the control. The species Canthidium sp.1, Canthidium sp. 2, Ateuchus sp., Canthon nigripenne, Canthonella sp. and D. sericeus came to all three bait types. Eight species were found in the baits with human dung, where Canthidium sp.1 (49%) and D. sericeus (39%) were the most common. A significant difference in attractiveness of the different baits was observed; the highest abundance found in traps baited with human dung (F = 36.59; g.l. = 3; p < 0.0001). A significant difference in richness was observed between rainy and dry seasons (F = 12.29; g.l. = 1; p < 0.001), the highest richness found in the dry season.<br>Nesse estudo, realizado em um remanescente de Floresta Atlântica Brasileira, três tipos de fezes de animais com distintos hábitos alimentares foram utilizados para verificar possíveis diferenças de atratividade dessas fezes por Scarabaeinae e a influência da sazonalidade nessa atratividade. Três habitats foram amostrados: borda, clareira e núcleo da floresta, cada um com 40 armadilhas de queda ("pitfall"). Um total de 2137 besouros foi coletado de agosto de 2005 a julho de 2006. Canthidium sp. 1 (43%) e Dichotomius sericeus (41%) foram as espécies mais abundantes. Do número total de besouros coletados, 80,5% foram atraídos para fezes humanas, 11% para fezes de jaguar, 7,8% para fezes de cobo e 0,7% para o controle. As espécies Canthidium sp.1, Canthidium sp. 2, Ateuchus sp., Canthon nigripenne, Canthonella sp. e D. sericeus foram aos três tipos de isca. Oito espécies foram encontradas nas iscas com fezes humanas, onde Canthidium sp.1 (49%) e D. sericeus (39%) foram as mais abundantes. Diferença significativa de atratividade por diferentes iscas foi observada; a maior abundância foi evidenciada em armadilhas iscadas com fezes humanas (F = 36.59; g.l. = 3; p < 0.0001). Diferença significativa foi observada na riqueza entre as estações chuvosa e seca (F = 12.29; g.l. = 1; p < 0.001) sendo a maior riqueza verificada na estação seca
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