SNAKES FROM THE PONTAL DO TRIÂNGULO MINEIRO REGION, CERRADO DOMAIN, SOUTHEASTERN BRAZIL

Snakes have a great ecological importance, interacting to others species and feeding on some that are considered plagues and illness reservoirs. The present work aims to list the snake species present in the Ituiutaba Municipality. The data were collected through previously preserved specimens deposited in zoological collections, visual searches and occasional encounters. Fifty six snakes were analyzed, and classified in twenty three species, distributed in five families. The richness found is relatively high, considering the elevated degree of modification in the natural environment, where only 15% remain intact. Of analyzed individuals, several have substantial medical and pharmacological importance, mainly the genera Bothrops and Crotalus. The present study contribute with the knowledge about the Cerrado snake assemblage, and emphasizes the importance of knowing the local fauna, mostly in environments with anthropic action, where there evident habitat loss.Snakes play an important ecological role, interacting with other species and feeding on some that are considered pests and illness vectors. The present work aims to list the snake species present in the Municipality of Ituiutaba, southeastern Brazil. The data were obtained from preserved specimens deposited in zoological collections, visual surveys and occasional encounters. Fifty-seven individuals were analyzed, and we identified twenty-three species, distributed in five families. The number of species found is relatively high, considering the advanced degree of alterations in the natural environment, where only 15% remains intact. In our sample, we identified individuals of two viperid genera with medical and pharmacological importance. The present study contributes to the knowledge on snake assemblages in the Cerrado, and emphasizes the importance of inventories of the local fauna, mostly in environments with anthropic action, resulting in loss of habitats

Data from: Seasonal variation in foraging group size of crab-eating foxes and hoary foxes in the Cerrado biome, Central Brazil

In regions with a pronounced dry season, such as the Cerrado Biome (Brazilian savannah), climate seasonality may affect food availability for canid species and, consequently, their foraging behavior. We investigated seasonal variation in foraging group size of crab-eating foxes (Cerdocyon thous) and hoary foxes (Pseudalopex vetulus) in the Cerrado region for three consecutive years. Data were obtained by direct observations of foraging foxes during spotlight surveys. Both species were sighted foraging individually or in pairs with or without their juvenile offspring. However, crab-eating foxes foraged in pairs more frequently in the wet season and individually more frequently in the dry season whereas hoary foxes foraged mostly individually throughout the year. The higher frequency of solitary foragers in the dry season is possibly a response to the seasonal shortages in the availability of clumped and locally abundant food resources such as fruit and insects, important items in the diet of the crab-eating fox during the wet season. The absence of seasonal variation in foraging group size of the hoary fox may be related to its specialized food habits, since termites predominate in the diet of this species in both seasons

Lemos_foxes_Metadata_Limoeiro_2011

Lemos_foxes_Metadata_Limoeiro_201

Lemos_foxes_TransectsID_Limoeiro_2012Jun28

Lemos_foxes_TransectsID_Limoeiro_2012Jun2

Interference competition between the crab-eating fox and the hoary fox

<p>Poster presented at the I South American Mastozoology Congress on 2006 about a paper published by our research group on the interspecific competition between two sintopic canids of Brazilian Cerrado, the crab-eating fox and the hoary fox.</p> <p>The link for the complete work follows below and the paper is free.</p

Influence of environmental factors on benthic macroinvertebrate communities of urban streams in Vereda habitats, Central Brazil Influência de variáveis ambientais na comunidade de macroinvertebrados bentônicos de córregos urbanos de Veredas, Brasil Central

AIM: Veredas and the aquatic and semi-aquatic communities play a key role in watershed protection in the Cerrado Biome. Information about the effects of physical and chemical variables and habitat integrity on benthic communities has been increased in recent years; however, there is no study evaluating the influence of urbanization on macroinvertebrates of Vereda streams. Thus, improving the knowledge of the relationship between abiotic properties and benthic fauna is very important for understanding the functioning of ecological processes and health of aquatic ecosystems. This study investigated the influence of physical and chemical variables on benthic macroinvertebrate communities along a gradient of anthropogenic disturbance in four Vereda streams in Uberlândia (MG), one in a preserved area and three in the urban area; METHODS: samplings were collected during the dry and rainy seasons; RESULTS: principal component analysis separated the stream in the preserved area from those in the urban area by having lower values of BOD, COD, sediment size, conductivity, detergents, pH, deposited solids and total dissolved solids. Pollution sensitive groups (e.g., Ephemeroptera and Trichoptera) were associated to the stream in the preserved area, and more tolerant groups (e.g., Chironomidae and Oligochaeta) had greater abundance in the streams of the urban area. Canonical Correspondence Analysis indicated that dissolved oxygen, conductivity, BOD, oil and grease, and turbidity explained 56% of the variance in the distribution and abundance of macroinvertebrates; CONCLUSIONS: Benthic communities of Vereda streams in urban areas in the Cerrado Biome seem to be highly affected by human activities that increase water organic pollution and sedimentation.OBJETIVO: Veredas e comunidades aquáticas e semi-aquáticas desempenham importante papel na proteção das bacias hidrográficas no Bioma Cerrado. Informações sobre efeitos de variáveis físico-químicas e da integridade do habitat nas comunidades de macroinvertebrados bentônicos têm aumentado nos anos recentes, entretanto, não há estudos avaliando a influência da urbanização nas comunidades de macroinvertebrados em córregos de veredas. Assim, ampliar o conhecimento da relação entre as variáveis abióticas e fauna bentônica é muito importante para a compreensão do funcionamento dos processos ecológicos e da integridade dos ecossistemas aquáticos. Este estudo investigou a influência de variáveis físicas e químicas nas comunidades de macroinvertebrados bentônicos ao longo de um gradiente de distúrbios antrópicos em quatro córregos de Vereda em Uberlândia (MG); um em uma área preservada e três na área urbana MÉTODOS: as amostras foram coletadas nas estações seca e chuvosa RESULTADOS: A análise de componentes principais separou o córrego da área preservada daqueles da área urbana por apresentar menores valores de DBO, DQO, tamanho do sedimento, condutividade, detergentes, pH, sólidos depositáveis e sólidos totais dissolvidos. Grupos sensíveis à poluição (e.g., Ephemeroptera e Trichoptera) foram associados ao córrego da área preservada e grupos mais tolerantes (Chironomidae e Oligochaeta) tiveram maior abundância nos córregos da área urbana. A Análise de Correspondência Canônica indicou que oxigênio dissolvido, condutividade, DBO, óleos e graxas e turbidez explicaram 56% da variação na distribuição e abundância de macroinvertebrados; CONCLUSÕES: comunidades bentônicas de córregos de Vereda em áreas urbanas no Bioma Cerrado parecem ser altamente afetadas pelas atividades humanas que aumentam a poluição orgânica da água e a sedimentação

Patterns of ant species diversity and turnover across 2000 km of Amazonian floodplain forest

Aim To determine the effect and relative importance of geographic and local environmental factors on species richness and turnover of ant assemblages in floodplain forests across the Amazon basin. Location Twenty-six mature forest sites scattered along the entire extension of the Amazon River in Brazil. The study area encompassed nearly 18° of longitude and 3.5° of latitude. Methods Systematic collections of ants were performed at each site during the low-water season (i.e. when forests are not inundated) using three complementary sampling methods. We used variance partitioning techniques to assess the relative effects of the spatial (latitude and longitude) and environmental (rainfall, length of the dry season and flood height) variables on ant species richness and composition. Results There was a twofold variation in the number of species per site, which was largely explained by inter-site variations in rainfall seasonality and flooding intensity. In general, there were more species at sites located in the western part of the basin, where the dry season is less severe, or near the river estuary, where precipitation is also high and flooding is less intense. Ant community composition was also affected by environmental heterogeneity. For instance, some species only occurred at those sites less affected by the river's seasonal flooding, whereas others were mostly associated with the drier or wetter regions of the basin. In addition, the turnover of species increased significantly as geographic distances increased. Nevertheless, the rate of change was small given that many species had a broad distribution across the study area. Main conclusions Ant distribution patterns along the floodplain forests of the Amazon appear to be controlled to a relatively large extent by the current gradient in flooding intensity and - most importantly - in precipitation. Altered rainfall regimes resulting from global warming and land-use change thus have the potential to influence these patterns. © 2009 Blackwell Publishing Ltd

Dinâmica da comunidade arbórea em uma floresta estacional semidecidual sob queimadas recorrentes

Os efeitos do fogo sobre a mortalidade de árvores podem alterar a composição e estrutura da vegetação, dependendo da intensidade, frequência e duração das queimadas. Monitoramos áreas de floresta sujeitas a diferentes frequências de fogo no Parque Estadual da Serra Azul, Barra do Garças, MT: 0,9 ha queimaram em 2007 (Q1) e 0,9 ha em 2005 e 2007 (Q2). A dinâmica foi referente ao intervalo médio de 2,02 anos, de forma que o primeiro levantamento (T1) ocorreu em outubro/2006-maio/2007 e o segundo levantamento (T2) em março/2009, considerando indivíduos com PAP > 15 cm. A diversidade (H') e a riqueza de espécies (estimada por Jackknife) foram maiores em Q2, nos dois levantamentos. Ocorreu a diminuição significativa na densidade em Q1 e Q2, mas a proporção de indivíduos mortos foi maior em Q1. Os parâmetros da dinâmica baseados no número de indivíduos e na área basal não diferiram entre Q1 e Q2. O aumento da diversidade na área sujeita a maior frequência de queimadas pode ser explicada pela hipótese de distúrbio intermediário. Entretanto, apesar da mortalidade e recrutamento não terem diferido entre Q1 e Q2, as altas taxas de mudança, independentes da frequência do fogo, sugerem futuras alterações florísticas e estruturais na floresta, caso as queimadas continuem ocorrendo na área