No abstract

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.

Even though the great majority of the biomass and diversity of mammals in tropical forests inhabit the canopy (Eisenberg & Thorington 1973), most knowledge of this group is based on forest-floor samples (Lowman & Moffett 1993). Studies that include trapping efforts in the canopy are becoming increasingly common (Grelle 2003, Lambertet al. 2005, Malcolm 1995, Pattonet al. 2000, Vieira & Monteiro-Filho 2003, Vosset al. 2001), but aspects on the ecology of arboreal small mammals still remain poorly understood. Many species of non-flying mammals co-occur in the canopy and, thus, are expected to use niche dimensions differently to permit coexistence (Cameronet al. 1979). Despite the difficulties of access to and in understanding the three-dimensional use of the arboreal strata by the different species (Emmons 1995), some studies have demonstrated that the differential use of the habitat (Cunha & Vieira 2002, Gentile & Fernandez 1999), of food items (Cácereset al. 2002, Santoriet al. 1995) or both (Leiteet al. 1996, Mauffrey & Catzeflis 2003), include strategies involved in the division of resources.

Habitat fragmentation reduces biodiversity and affects ecological processes that are fundamental for maintaining ecosystem services. We investigated how landscape structure-percent forest cover, patch density, percent cover by edge, perimeter-area ratio, and spatial heterogeneity-affects the diversity of mammalian carnivores at multiple extents within 22 Atlantic Forest landscapes. We hypothesized that 1) species richness of carnivores is positively related to forest cover; and 2) the occurrence of species will vary according to its sensitivity to forest loss and its preference for forest or open areas. Species richness, composition, and occurrence of mammalian carnivores were correlated with several landscape structure metrics. Due to a high correlation among the metrics, we adopted forest cover as the principal predictor variable. We compared a forest cover model to a null model using Akaike Information Criterion (AICc), and evaluated other fragmentation metrics using a redundancy analysis. Carnivore species richness was positively related to forest cover and negatively associated with other fragmentation metrics. However, the responses to landscape structure differed among species, possibly due to their differences in habitat use. Landscape configuration is an important factor influencing carnivore species composition. Forest cover can explain some, but not all, carnivore species occurrence. Our results reinforce the protection of forests as fundamental to the conservation of carnivore species and the ecological processes in which they participate.O processo de fragmentação de habitat reduz a biodiversidade e afeta processos ecológicos fundamentais para a manutenção de serviços ecossistêmicos. Nós investigamos como as métricas de estrutura da paisagem-cobertura florestal, densidade de manchas, cobertura porcentual de borda, relação perímetro-área e heterogeneidade espacial-afetam a diversidade de mamíferos carnívoros em múltiplas extensões em 22 paisagens da Mata Atlântica. Orientamo-nos pelas seguintes hipóteses: a) a riqueza de carnívoros é relacionada positivamente com a cobertura florestal; b) a ocorrência das espécies varia de acordo com a sua sensibilidade à perda de floresta e à preferência por florestas ou áreas abertas. Riqueza, composição e ocorrência de mamíferos carnívoros foram relacionadas com várias métricas da paisagem. Devido à alta correlação entre as métricas, adotamos a quantidade

No abstract

Defaunation is a key ecological issue that has only recently been given sufficient attention. As predicted, evidence so far indicates loss of larger species followed by medium-sized species, leading to cascading effects that propagate throughout entire communities and ecosystems. The Atlantic Forest is among the most important global biodiversity hotspots. These regions have historically been impacted by habitat loss and fragmentation, resulting in landscape changes and negative impacts upon animal communities. This study evaluates community characteristics of medium- and large-sized mammals in subtropical Atlantic Forest, southern Brazil. We gathered data on mammal occurrence using 108 cameras traps located across 8 protected areas. We then tested whether landscape differences impact mammal richness, composition, and community complexity. Specifically, we used a regression tree to evaluate compositional differences as a function of landscape configuration. We analyzed data for 26 species in total, with the number of species per area ranging from 9 to 17. Changes in mammal composition at the landscape scale were most strongly associated with human occupation. Areas with strong human occupation had low species richness, with a predominance of medium-sized omnivores and insectivores species; these conditions led to high defaunation indices. Community complexity was greater in areas with low human occupation, where carnivores (Felidae) were more abundant. Differences in species composition were also linked to altitudinal bands and the ratio of period of time with protected status versus history of land exploitation in a particular area. Analysis of functional groups indicated that intense human occupation had negative effects on larger species, a process that may have impending consequences. Despite defaunation being a serious ecological issue, we assert that taking prompt action may limit or potentially reverse effects of defaunation before the most dramatic changes take place. Defaunação é uma questão ecológica chave e que só recentemente tem recebido atenção suficiente. Como previsto, as evidências até agora indicam perda de espécies de maior porte, seguida por espécies de médio porte, levando à efeitos em cascata que se propagam em todas as comunidades e ecossistemas. A Mata Atlântica está entre os mais importantes hotspots de biodiversidade mundiais. Essa região tem sido historicamente impactada pela perda e fragmentação de hábitat, resultando em mudanças na paisagem e impactos negativos nas comunidades animais. Este estudo avalia características de comunidades de mamíferos de médio e grande porte na Mata Atlântica subtropical, sul do Brasil. Nós reunimos dados sobre ocorrência de mamíferos utilizando 108 armadilhas fotográficas instaladas em oito áreas protegidas. Em seguida, avaliamos se as diferenças de paisagem impactam a riqueza, composição e a complexidade das comunidades de mamíferos. Especificamente, nós usamos uma análise de árvore de regressão para avaliar as diferenças na composição das comunidades em função da configuração da paisagem. Analisamos ​​dados de 26 espécies no total, com o número de espécies por área variando 9 a 17. As alterações na composição de mamíferos na escala da paisagem foram mais fortemente associadas à ocupação humana. As áreas com maior ocupação humana tiveram baixa riqueza de espécies, com predominância de espécies onívoras e insetívoras de médio porte, e, estas condições geraram índices de defaunação elevados. A complexidade das comunidades foi maior em áreas com baixa ocupação humana, onde carnívoros (Felidae) foram mais frequentes. As diferenças na composição de espécies também foram ligadas às quotas de altitude, assim como à razão entre o período de tempo com estatuto de proteção e o tempo de exploração de cada área. A análise com abordagem de grupos funcionais indicou que a maior ocupação humana teve efeitos negativos sobre as espécies maiores, um processo com consequências negativas iminentes. Apesar da defaunação ser uma importante questão ecológica, nós acreditamos que um conjunto de ações conservacionistas imediatas podem potencialmente limitar ou reverter os efeitos da defaunação antes que mudanças mais dramáticas acontecem.

No abstract

The objectives of this research were to: 1. evaluate the circadian activity patterns of lowland tapirs (Tapirus terrestris) throughout the seasons and 2. study the influence of moonlight, temperature and rainfall on the activity patterns and habitat selection of this species, in the coastal sand shrub in southern Brazil. From June 2005 to June 2006, eight tapirs were monitored in a large enclosure containing open and vegetation-covered areas, using four camera traps. Differences in activity patterns within seasons were found. Tapir predominately presented nocturnal-crepuscular activity; however, they differed in the winter, with cathemeral activity patterns. Covered areas were mostly used during periods of extreme temperatures, with less diurnal and more nocturnal activities within these areas, on hotter days. Activity in open areas mainly occurred during periods of intermediate temperatures, both during the day and in the night. Moonlight intensity did not influence nocturnal activities. On days of precipitation of 34 mm or more, there was no record of open-area activities, despite constant activity in covered-area.