Parentage test in broad-snouted caimans (Caiman latirostris, Crocodylidae) using microsatellite DNA

In this study, microsatellite markers, developed for Alligator mississipiensis and Caiman latirostris, were used to assess parentage among individuals from the captive colony of Caiman latirostris at the University of São Paulo, in Piracicaba, São Paulo, Brazil. Many of the females in the colony were full siblings, which made maternal identification difficult due to genotypic similarity. Even so, the most likely mother could be identified unambiguously among offspring in most of the clutches studied. Two non-parental females displayed maternal behavior which would have misled managers in assigning maternity based on behavior alone. This set of variable loci demonstrates the utility of parentage testing in captive propagation programs

Distribution of populations of broad-snouted caiman (Caiman latirostris, Daudin 1802, Alligatoridae) in the São Francisco River basin, Brazil

We surveyed populations of the broad-snouted caiman, Caiman latirostris, throughout the São Francisco River basin, from Três Marias reservoir, State of Minas Gerais, to the river delta, at the boarder of Sergipe and Alagoas states. We registered the occurrence of crocodilians in 61% of all surveyed localities (n = 64), in which the presence of C. latirostris was confirmed in 44% of the surveyed sites. Caimans occurred in both lentic and lotic habitats, although there was a preference for small dams, oxbow lakes and wetlands. Despite the hunting pressure and human impact on natural habitats, our results indicate that the populations of C. latirostris in the São Francisco basin are not fragmented

Diversity and distribution patterns of medium to large mammals in a silvicultural landscape in south-eastern Brazil

Agricultural landscapes cover approximately 35% of Brazil and are the second greatest threat to biodiversity worldwide. In Brazil, seven millions hectars of land is covered with Eucalyptus plantations, which is considered to have low conservation value. However, studies have shown that heterogeneous silvicultural landscapes, made up of Eucalyptus matrices and patches dedicated to conservation, are able to support a considerable diversity of wild mammals. This study aims to assess the diversity and distribution patterns of medium-to-large-sized mammals in a silvicultural landscape in Angatuba, São Paulo, Brazil. Nineteen species were detected by camera traps within the study area. Diversity indices did not vary among habitat types (i.e., native vegetation, abandoned pasture and Eucalyptus plantations), suggesting that the species use the landscape as a whole. A relatively diverse range of predator species was found in the area, suggesting that future monitoring programs should focus on predator-prey relationships. A low diversity of frugivores was detected, indicating that management actions should be taken to facilitate their local recovery. Our results stress the fundamental importance of the conservation areas (Permanent Preservation Areas and Legal Reserve) in silvicultural landscapes, as these areas help maintain complexity of the landscape structure

Genetic Diversity of New World Crocodilians

Genetic diversity is one of the most important attributes of any population; it is defined as the variation in the amount of genetic information within and among individuals of a population, species, assemblage, or community. It can be expressed as differences between individuals at different levels, such as morphological features, structure and chromosomal number, and polymorphisms of sequences of DNA or proteins. An assessment of genetic diversity is fundamental to population genetic studies and has extremely important applications in conservation biology and the development of management and sustainable use plans. This chapter discusses the main indices that allow analyzing genetic variability and population structure of New World crocodilian populations, the methodologies used to estimate these indices, and the principal population genetic data available for these species. The effective population size concept is also discussed, a fundamental parameter in the study of principally those crocodile populations that have been drastically reduced in size and/or suffered fragmentation of their environments.Fil: Amavet, Patricia Susana. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Barban Zucoloto, Rodrigo. Universidade Federal da Bahia; BrasilFil: Hrbek, Tomas. Universidad Federal del Amazonas.; BrasilFil: Pires Farias, Izeni. Universidad Federal del Amazonas.; Brasi