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Atibaia, Brazil

Azevedo F.C.C.,Federal University of Sao Joao del Rei | Azevedo F.C.C.,Instituto Pro Carnivoros | Verdade L.M.,University of Sao Paulo
Journal of Zoology | Year: 2012

Advances in the understanding of ecological factors determining predator-prey interactions have provided a strong theoretical background on diet preferences of predators. We examined patterns of jaguar predation on caiman in southern Pantanal, Brazil. We investigated factors affecting predation rates and vulnerability of caiman to predation by jaguars. We recorded 114 caiman mortality incidents. Predation accounted for 62.3% (n = 71) of all caiman found dead, while other causes of mortality (nonpredation) accounted for 37.7% (n = 43). We found that jaguars prey on a broad size range of caiman body and caiman predation was influenced by distance to forests. During dry seasons, 70% (n = 49) of deaths were due to predation, while 30% (n = 21) were due to nonpredation causes. However, we found no significant relationship between annual and monthly killings of caiman and rainfall totals by year and month (r = 0.130, r = -0.316). The annual flooding regime may be a more important factor influencing prey selection by jaguars. Although neotropical crocodilians are relatively well studied, their interactions with jaguars have been mostly ignored and should be prioritized in future studies. © 2011 The Authors. Journal of Zoology © 2011 The Zoological Society of London. Source

Eizirik E.,Pontifical Catholic University of Rio Grande do Sul | Eizirik E.,U.S. National Institutes of Health | Eizirik E.,Instituto Pro Carnivoros | Murphy W.J.,Texas A&M University | And 5 more authors.
Molecular Phylogenetics and Evolution | Year: 2010

The mammalian order Carnivora has attracted the attention of scientists of various disciplines for decades, leading to intense interest in defining its supra-familial relationships. In the last few years, major changes to the topological structure of the carnivoran tree have been proposed and supported by various molecular data sets, radically changing the traditional view of family composition in this order. Although a sequence of molecular studies have established a growing consensus with respect to most inter-familial relationships, no analysis so far has included all carnivoran lineages (both feliform and caniform) in an integrated data set, so as to determine comparative patterns of diversification. Moreover, no study conducted thus far has estimated divergence dates among all carnivoran families, which is an important requirement in the attempt to understand the patterns and tempo of diversification in this group. In this study, we have investigated the phylogenetic relationships among carnivoran families, and performed molecular dating analyses of the inferred nodes. We assembled a molecular supermatrix containing 14 genes (7765 bp), most of which have not been previously used in supra-familial carnivoran phylogenetics, for 50 different genera representing all carnivoran families. Analysis of this data set led to consistent and robust resolution of all supra-familial nodes in the carnivoran tree, and allowed the construction of a molecular timescale for the evolution of this mammalian order. © 2010 Elsevier Inc. Source

Norris D.,Av. Mariland 1367 1001 | Michalski F.,University of Sao Paulo | Michalski F.,Instituto Pro Carnivoros
ORYX | Year: 2010

Monitoring rare and elusive species for effective management and conservation is particularly challenging and often demands the development of specialized techniques. Scat surveys have been applied to monitor a variety of rare species but relatively little attention has been given to the development of appropriate sampling designs. To determine if scat surveys could be applied to compare the distribution of species across three habitats of a fragmented region in the Brazilian Amazon, the removal of human (n = 27) and jaguar (n = 27) scat samples in forest, riparian corridor and pasture habitats was recorded for 24 hours. Dung beetles were responsible for removing the majority of samples (71%) and a generalized linear mixed effect model revealed significant influence of habitat and scat type on removal probability, with forest and riparian corridors having higher removal compared with samples in pasture habitats. Although non-invasive scat surveys can potentially address fundamental broad-scale conservation and management questions, our results demonstrate that scat surveys in the tropics must account for differences in scat removal rates between habitats and target species before conclusions can be drawn regarding patterns of habitat use. © 2010 Fauna & Flora International. Source

Morato R.G.,Instituto Pro Carnivoros
Tropical Conservation Science | Year: 2013

We surveyed Brazilian protected areas to assess the scale of big cat hunting within the National Protected Areas System. A questionnaire was emailed to managers of 297 reserves, with a response rate of 33.7%. One-third of respondents reported that jaguars (Panthera onca) and/or pumas (Puma concolor) have been hunted recently (i.e., within the last two years) in their reserves, resulting in the deaths of at least 60 cats. Hierarchical partitioning analysis revealed that degree of restriction to human use in the reserve (as a four-level rank variable) was the most important factor affecting the probability of a manager reporting big cat hunting, with hunting reported three times more frequently in the less restrictive reserves than in the more restrictive ones. Though our study represents only a small fraction of the problem, it confirms that hunting is widespread and represents a threat to carnivore conservation within Brazilian protected areas. © Elildo Alves Ribeiro de Carvalho Jr and Ronaldo Gonçalves Morato. Source

Trinca C.S.,Federal University of Rio Grande do Sul | Trinca C.S.,Grande Rio University | Jaeger C.F.,Grande Rio University | Eizirik E.,Grande Rio University | Eizirik E.,Instituto Pro Carnivoros
Biological Journal of the Linnean Society | Year: 2013

Non-invasive genetic analysis has been frequently employed to estimate ecological and population parameters for many secretive and/or threatened species. However, Neotropical carnivores have so far been scarcely targeted by such studies. The Neotropical otter (Lontra longicaudis) is a poorly-known species for which local levels of genetic diversity and demographic parameters are virtually absent. We employed non-invasive sampling and amplification of microsatellite loci to investigate population size and density, spatial organization, and relatedness of a wild Neotropical otter population in an Atlantic forest area in southern Brazil. We directly identified 28 individuals and estimate a rather high population density at the study site. Spatial organization analysis indicated that male cumulative displacement was higher than that of females, with the latter sex showing evidence of philopatric behaviour. Also, the reconstruction of genealogical relationships suggests that spatial organization in this otter appears to be influenced by relatedness. By allowing the testing of specific hypothesis targeting these issues, our results provided important glimpses into the Neotropical otter's population biology. Moreover, the findings of the present study reaffirm the power of non-invasive genetics to investigate the biology of this elusive species, and open up new avenues for ecological and demographic studies of other Neotropical carnivores. © 2013 The Linnean Society of London. Source

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