Pampean lizard assemblage from subtropical Brazil: a temporal analysis

The increasing human occupation of natural environments is one of the greatest threats to biodiversity. To mitigate the negative anthropogenic effects, it is necessary to understand the characteristics of natural populations and the natural history of species. A study was conducted with an assemblage of lizards from a disturbed area of the Pampa biome, from February 2001 to January 2004. The assemblage showed a unimodal seasonal pattern, with the recruitment period occurring during the warmer months. The captures were seasonal for two of the three monitored years, and concentrated within warmer months. The minimum temperature explained the number of catches for the assemblage as a whole. However, when the species were analyzed individually, the temperature only explained the seasonal occurrence of Teius oculatus. The abundance of species was significantly different in the third year of study for Cercosaura schreibersii and Ophiodes striatus. This latter species was no longer registered in the study area from May 2003 until the end of the study. Therefore, O. striatus may be more sensitive to environmental changes, considering the events of change in vegetation during the study. With frequent and increasing environmental disturbances, it is necessary to take conservation measures and encourage the increase of knowledge on Pampean lizards.O crescimento da ocupação humana sobre ambientes naturais é uma das maiores ameaças à biodiversidade. Para amenizar os efeitos negativos antropogênicos, é necessário entender as características das populações naturais, e a história natural das espécies. Um estudo foi conduzido com uma assembeia de lagartos de uma área perturbada do Pampa, de fevereiro de 2002 a janeiro de 2004. A assembleia apresentou padrão sazonal unimodal, com recrutamento ocorrendo durante os meses mais quentes. As capturas foram sazonais durante dois dos três anos monitorados, e concentradas nos meses mais quentes. A temperatura mínima explica o número de capturas para a assembleia como um todo. Entretanto, quando as espécies foram analisadas individualmente, a variável explica apenas a ocorrência sazonal de Teius oculatus. A abundância das espécies foi significativamente distinta no terceiro ano de estudo para Cercosaura schreibersii e Ophiodes striatus. Essa última espécie não teve mais registros na área de maio de 2003 até o final do estudo. Assim, O. striatus pode ser mais sensível às udanças abientais, considerando os eventos de udança na vegetação ocorridas durante o estudo. Com as frequentes e crescentes perturbações ambientais que o bioma vem sofrendo, são necessárias ações de conservação, e dar suporte para o aumento do conhecimento dos lagartos pampeanos

Reproductive modes in frogs and their unexpected diversity in the Atlantic Forest of Brazil (vol 55, pg 207, yr 2005)

Univ Estadual Paulista, Dept Zool, Sao Paulo, BrazilUniv Estadual Paulista, Dept Zool, Sao Paulo, Brazi

Breeding activity patterns, reproductive modes, and habitat use by anurans (Amphibia) in a seasonal environment in the Pantanal, Brazil

Annual patterns of breeding activity, reproductive modes, and habitat use are described for a frog community in a seasonal environment, in the southern Pantanal, Mato Grosso do Sul, Brazil. Data were collected monthly between January 1995 and December 1998. A total of 24 species from four families; Bufonidae (3 species), Hylidae (10 species), Leptodactylidae (9 species), and Microhylidae (2 species) were registered. Three reproductive activity patterns are recognized among these species: continuous, explosive, and prolonged; 50% of the species were explosive breeders. Seasonal pattern of reproduction was verified for three analyzed years (1995-1997) most species reproduced during the rainy season (Nov-Jan). The reproduction was aseasonal in 1998; unexpected rains in the dry season lead to an unusual breeding activity. Five reproductive modes were noted - 62.5% of the species have the generalized aquatic mode, and 33.3% deposit eggs embedded in foam nests. Many species used the same sites for reproduction, although temporal partitioning and calling site segregation was observed. The occurrence of many species that exhibit explosive breeding early in the rainy season is common in seasonal and open environments with variable and unpredictable rainfall, as is the case in the Pantanal

Aspects of the reproductive ecology of trachycephalus cunauaru (Anura: Hylidae) in the southern amazon

Trachycephalus cunauaru is an Amazonian hylid that uses phytotelmata to reproduce. There is relatively little information about the species, mainly due to the difficulty of accessing their reproductive sites. In this study, we gathered data on the ecology and natural history of T. cunauaru in the southern Amazon, in the state of Mato Grosso, Brazil. In addition to natural phytotelmata, we used buckets installed at a height of 10 m as artificial phytotelmata. We compared physical and chemical characteristics, as well as the presence of tadpoles between natural and artificial phytotelmata. We also collected data on the reproductive behavior of the species through the use of camera traps. We recorded a density of 14.1 reproductive sites per km². Environmental parameters differed significantly between artificial and natural phytotelmata. In artificial sites, the presence of tadpoles was directly related to trees with a larger diameter. We registered oophagy for the first time for the species and observed that males can use more than one phytotelm. We also recorded the presence of snakes within the reproductive sites. We determined that artificial sites and digital camera traps are a satisfactory alternative for behavioral observations of T. cunauaru and possibly for other species with a similar habit.Full Tex