Similar regional-scale survival of tropical and southern temperate birds from the New World.

The general assumption that the survival patterns of tropical and southern temperate birds are similar lacks empirical data from higher latitudes. Regional comparisons of New World species are rare, and this assumption has been based on data from African studies. Here, we estimate the survival rates of 88 tropical and southern temperate bird populations (69 species) from eight localities in South America to evaluate the hypothesis that the survival of these populations is homogeneous at the regional scale. We estimated survival based on the Cormack-Jolly-Seber model and compared values from different environments. The survival estimates ranged from 0.30 to 0.80 (0.56 ± 0.12). Apparent survival did not differ significantly between low-latitude tropical environments (03°S) and the other sites from high-latitudes (between 22° and 34°S). Despite a predicted positive trend, body size was not significantly related to survival among passerines. On the other hand, phylogenetic relationships explained more than a third of the variation in bird survival. Based on the largest available database on South American bird species, our findings support the hypothesis that bird survival is homogeneous, at the regional scale, along the southern hemisphere. In particular, we reinforce the hypothesis that climatic variation has a limited influence on bird survival in the southern hemisphere.

Species richness and distribution patterns of the snake fauna of Rio Grande do Norte state, northeastern Brazil.

The Neotropics are one of the richest regions in biodiversity globally. Still, much remains unknown about the mechanisms and processes responsible for the accumulation of species in this region. Among the many limitations on our current knowledge on the region's biodiversity, understanding of community composition and species distributions is limited and greatly biased in many Brazilian regions. We present information on species composition, habitat use, geographic distribution, taxonomic accounts, and conservation of snakes from Rio Grande do Norte state, Northeastern Brazil. We compiled, from primary and literature data, 851 snake records from seven families and 47 species, with five new records for the state. Species are mainly terrestrial and semi-arboreal and associated with at least six vegetation types from Caatinga and Atlantic Forest domains. None of the species is listed in threatened categories of IUCN, while two species are listed in the Brazilian Threatened Fauna list. Our data covers 32.34% of the state's area, a consequence of locally limited inventories and lack of long-term studies on snakes' fauna. The richest areas within the state are near large cities, which lack protected areas for the species they harbor, and highlights the necessity of protective policies and conservation actions.

Dangerous neighborhood: saurophagy between syntopic Tropidurus lizards / Vizinhança perigosa: saurofagia entre lagartos Tropidurus sintópicos

Saurophagy constitutes an important source of mortality among lizards and has been reported for the genus Tropidurus. However, the extension of this behavior remains unknown. Herein, we record the predation of T. jaguaribanus by its congener T. hispidus. This is the first report of saurophagy among different species of syntopicTropidurus. Furthermore, whereas published records of saurophagy tend to be directed against juveniles, this case involved two adult individuals.

A saurofagia constitui uma importante fonte de mortalidade entre lagartos e tem sido reportada para o gênero Tropidurus. Contudo, a extensão deste comportamento permanece desconhecida. Neste estudo registramos a predação de T. jaguaribanus por seu congênere T. hispidus. Este é o primeiro caso de saurofagia entre diferentes espécies de Tropidurus sintópicos. Além disso, embora a saurofagia tenda a ser direcionada contra jovens, este caso envolveu dois indivíduos adultos.