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Rapid coagulation of reptile blood often hinders its use in studies in remote and difficult-to-access areas, necessitating chemical preservation. Therefore, understanding the potential effects of anticoagulants on the isotopic compositions of blood is essential to avoid issues in interpreting the results for ecological studies. In this study we aimed to verify whether the storage time of the blood tissue in anticoagulants can influence its isotopic compositions of the broad-snouted caiman (Caiman latirostris), an ectothermic top predator from eastern South America. Blood samples were obtained from ten adult females of C. latirostris from a commercial breeding facility in 2015. Samples were stored in vials containing ethylenediaminetetraacetic acid (EDTA) and sodium heparin (SH) and centrifuged after 2 and 8 h to separate red blood cells and plasma. No effect of time was found on the δ13C and δ15N of whole blood, plasma, and red blood cells in contact with the two types of anticoagulants, EDTA and SH. The findings have practical implications for researchers in this field, as they suggest that anticoagulants can be used effectively for at least eight hours under refrigeration.

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Abstract: Despite their negative environmental impacts, human-modified environments such as agricultural and urban landscapes can have a relevant role on biodiversity conservation as complements of protected areas. Such anthropized landscapes may have endangered, valuable, and nuisance species, although most of them do not fit in any of these categories. Therefore, in such environments we must deal with the same decision-making process concerning the same possible interventions proposed by Caughley (1994) to wildlife management, which are related to biological conservation, sustainable use, control/coexistence, and monitoring. Such decision-making process should be based on good science and good governance. On such context, the first step should be to implement multifunctional landscapes, which keep their primary mission of human use, but incorporate a second but fundamental mission of biological conservation. In this study we present a summary of the research carried out at the Biota Program of Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) in this field since the late 1990's and propose priorities for biodiversity research and governance in multifunctional landscapes for the near future.

Resumo Apesar de seus impactos ambientais negativos, ambientes modificados pelo homem, como paisagens agrícolas e urbanas, podem ter um papel relevante na conservação da biodiversidade como complementos de áreas protegidas. Tais paisagens antropizadas podem ter espécies ameaçadas, valiosas e incômodas, embora a maioria delas não se enquadre em nenhuma dessas categorias. Portanto, em tais ambientes devemos lidar com o mesmo processo de tomada de decisão sobre as mesmas possíveis intervenções propostas por Caughley (1994) para o manejo da vida selvagem, que estão relacionadas à conservação biológica, uso sustentável, controle/coexistência e monitoramento. Esse processo de tomada de decisão deve ser baseado em boa ciência e boa governança. Neste contexto, o primeiro passo deverá ser a implementação de paisagens multifuncionais, que mantenham a sua missão primordial de uso humano, mas que incorporem uma segunda, mas fundamental missão de conservação biológica. Neste estudo apresentamos um resumo das pesquisas realizadas no Programa Biota da Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) neste campo desde o final da década de 1990 e propomos prioridades para pesquisa e governança da biodiversidade em paisagens multifuncionais para o futuro próximo.

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Although the concept of optimal foraging has been extensively discussed, foraging efficiency is difficult to assess in vertebrates. In this study, we determined the foraging efficiency of the Brazilian cormorant, Nannopterum brasilianus Gmelin, 1789, by the direct, ad libitum observation of a group of four to thirteen individuals in an artificial pond at the University of São Paulo, Piracicaba, state of São Paulo, southeastern Brazil. Although this study was carried out in a highly anthropic environment, we can still conclude that the Brazilian cormorant is a relatively efficient browser and short-term diver. In anthropic environments, foraging success depends on the amount of time these birds spend diving, and stealing food is less common. Stealing occurs at relatively low rates but tends to be an efficient way to get food.(AU)

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Although the concept of optimal foraging has been extensively discussed, foraging efficiency is difficult to assess in vertebrates. In this study, we determined the foraging efficiency of the Brazilian cormorant, Nannopterum brasilianus Gmelin, 1789, by the direct, ad libitum observation of a group of four to thirteen individuals in an artificial pond at the University of São Paulo, Piracicaba, state of São Paulo, southeastern Brazil. Although this study was carried out in a highly anthropic environment, we can still conclude that the Brazilian cormorant is a relatively efficient browser and short-term diver. In anthropic environments, foraging success depends on the amount of time these birds spend diving, and stealing food is less common. Stealing occurs at relatively low rates but tends to be an efficient way to get food.

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Ecological niche is the multidimensional space comprising the resources used by an organism. Intraspecific variation in resource exploitation is common in reptile populations to maximize coexistence of individuals. The use of stable isotope analysis is an effective tool when there are variations in resource exploitation, since it can provide quantitative information about food consumption and habitat use. Mesoclemmys vanderhaegei (Bour, 1973) is a medium-sized turtle with a limited distribution in south central Brazil and Paraguay. In spite of that, little is known about its ecology. In this study we used stable isotope analysis to understand the intraspecific trophic niche variation in M. vanderhaegei at Serra das Araras Ecological Station, state of Mato Grosso, Brazil. The isotopic ratios of δ15N and δ13C were determined in claw samples collected from 14 males and 14 females. Isotopic niche width values were not statistically different between the sexes, there was a high degree of overlap between sexual niches and there were no relationships between isotopic compositions and body size. These results suggest that individuals of both sexes and throughout their ontogenetic development exploit food resources with the same isotopic baseline.(AU)

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Ecological niche is the multidimensional space comprising the resources used by an organism. Intraspecific variation in resource exploitation is common in reptile populations to maximize coexistence of individuals. The use of stable isotope analysis is an effective tool when there are variations in resource exploitation, since it can provide quantitative information about food consumption and habitat use. Mesoclemmys vanderhaegei (Bour, 1973) is a medium-sized turtle with a limited distribution in south central Brazil and Paraguay. In spite of that, little is known about its ecology. In this study we used stable isotope analysis to understand the intraspecific trophic niche variation in M. vanderhaegei at Serra das Araras Ecological Station, state of Mato Grosso, Brazil. The isotopic ratios of δ15N and δ13C were determined in claw samples collected from 14 males and 14 females. Isotopic niche width values were not statistically different between the sexes, there was a high degree of overlap between sexual niches and there were no relationships between isotopic compositions and body size. These results suggest that individuals of both sexes and throughout their ontogenetic development exploit food resources with the same isotopic baseline.

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Between July 2008 and May 2010, we conducted a trophic study on 12 Brazilian wild carnivore species through their faecal analysis in a silvicultural landscape at Angatuba municipality, southern São Paulo state. Predator faeces was identified by morphology, predator hair, and surrounding tracks; prey remnants within faeces were used for morphological identification of the prey. Among the recovered ectoparasites, there were 89 specimens of six tick species in 21 (4.0%) out of 523 analysed samples. Ticks were identified to species level, based on external morphological characters, as following: adults of Amblyomma ovale and Amblyomma sculptum; nymphs of Amblyomma brasiliense, Amblyomma calcaratum, Amblyomma dubitatum, A. ovale, and Ixodes schulzei; and larvae of Amblyomma sp. and Ixodes sp. Generally, the recovered immature ticks were associated with consumed prey (small birds or small mammals), whereas adults were associated with the predator itself, ingested during its self-grooming. Our data show that faeces is an additional information source on ticks in Brazil and which may provide information on ectoparasite-predator-prey interactions.

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Strategies to minimise intraspecific competition are common in wild animals. For example, individuals may exploit food resources at different levels of the food chain. Analyses of stable isotopes are particularly useful for confirming variations in an intraspecific niche because the chemical composition of animals tends to reflect both the food consumed and the habitats occupied by the species. However, studies using this methodology to investigate neotropical crocodilians are scarce. This study aimed to verify the existence of ontogenetic and sexual niche variation in broad-snouted caiman in a silvicultural landscape in Brazil through the use of carbon and nitrogen stable isotopes. The isotopic ratios of carbon and nitrogen were determined in claw samples collected from 24 juveniles, 8 adults, and 16 hatchlings of C. latirostris. We identified a discrete ontogenetic variation in the isotopic niche and sexual difference only for juveniles. These results may indicate differences in the exploitation resources and a consequent reduction in competition between age classes.

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The present study aims at assessing allometric relationships in the Sigmodontinae rodents (Calomys tener, Akodon cf. montensis, Necromys lasiurus, Oligoryzomys flavescens, and Oligoryzomys nigripes), and morphological variation among different habitats in human-dominated environments in Southeastern Brazil. We captured rodents using pitfall traps placed in Eucalyptus plantations, abandoned pastures, and remnants of secondary native vegetation, and took the following measurements: body mass, total length, body length, left hind foot length, and left ear length. Males were usually larger than females, except in N. lasiurus. There was no intraspecific difference in body condition among habitats, suggesting that Eucalyptus may not have a deleterious effect upon its residents. However, A. cf montensis from Eucalyptus plantations had longer feet than those from other vegetation associations, suggesting a possible adaptive response to the lower cover in the plantation environment, and its consequent higher predation risk, or alternatively that only individuals with greater dispersal ability are found in Eucalyptus plantations. Future studies should investigate a possible co-evolutionary predator-prey relationship, including rapid evolution by Sigmodontinae rodents in anthropogenic landscapes.

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The critically endangered black-faced lion tamarin, Leontopithecus caissara, has a restricted geographical distribution consisting of small mainland and island populations, each with distinct habitats in coastal southeastern Brazil. Necessary conservation management actions require an assessment of whether differences in habitats are reflected in use of space by the species. We studied two tamarin groups on the mainland at São Paulo state between August 2005 and March 2007, and compared the results with data from Superagui Island. Three home range estimators were used: minimum convex polygon (MCP), Kernel, and the new technique presented dissolved monthly polygons (DMP). These resulted, respectively, in home ranges of 345, 297, and 282 ha for the 12-month duration of the study. Spatial overlap of mainland groups was extensive, whereas temporal overlap was not, a pattern that indicates resource partitioning is an important strategy to avoid intraspecific competition. L. caissara large home ranges seem to be dynamic, with constant incorporation of new areas and abandonment of others through time. The main difference between mainland and island groups is the amount and variety of sleeping sites. A better understanding of the home range sizes, day range lengths, and territorial behavior of this species will aid in developing better management strategies for its protection. Additionally, the presented DMP protocol is a useful improvement over the MCP method as it results in more realistic home range sizes for wildlife species.

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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.

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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.

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Broad-snouted caiman's (Caiman latirostris) geographic distribution comprises one of the widest latitudinal ranges among all crocodilians. In this study we analyzed the relationship between geographic distance (along the species latitudinal range) and genetic differentiation using DNA microsatellite loci developed for C. latirostris and Alligator mississippiensis. The results suggest that there is a consistent relationship between geographic distance and genetic differentiation; however, other biogeographical factors seem to be relevant. The Atlantic Chain (Serra do Mar) seems to be an effective geographic barrier, as well as the relatively narrow (< or =1.5 km) sea channel between Cardoso Island and the continent. In addition, coastal populations seem to have been well connected in recent geological time (Pleistocene 16,000 years ago) all along the eastern Brazilian coast. Further studies should focus on the São Francisco River drainage, which is still poorly known for this species.

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Mammals play an important role in the maintenance and regeneration of tropical forests since they have essential ecological functions and can be considered key-species in structuring biological communities. In landscapes with elevated anthropogenic pressure and high degree of fragmentation, species display distinct behavioral responses, generally related to dietary habits. The landscape of Passa-Cinco river basin, in the central-eastern region of São Paulo State, shows a high degree of anthropogenic disturbance, with sugar cane plantations, eucalyptus forests, native semideciduous forest remnants and pastures as the key habitat types in the region. We surveyed medium to large mammals in those habitats and determined species richness and relative abundance for each of the following trophic categories: Insectivore/Omnivores, Frugivore/Omnivores, Carnivores, Frugivore/Herbivores and Herbivore/Grazers. Differences in species richness and relative abundance among habitats were tested using one-way analysis of variance, followed by Tukey test, considering 1) each of the trophic categories individually and 2) the set of categories together. Between July 2003 and June 2004, 284.4 km were walked and 22 species were recorded (20 native and two exotics). Analysis of variance did not detect differences in species richness for any of the trophic categories or for the assemblage. Considering relative abundance, the analysis detected significant differences only for the whole assemblage, with the assemblage being more abundant in sugar cane plantations compared to pastures. Our results indicate that the heterogeneous landscape of the study area is dominated by generalist species adapted to use different habitat types and food items.

Os mamíferos têm um importante papel na manutenção e regeneração das florestas tropicais, pois apresentam funções ecológicas essenciais e podem ser considerados como espécies-chave na estruturação das comunidades biológicas. Em paisagens com forte pressão antrópica e alto grau de fragmentação, as espécies apresentam respostas distintas, geralmente relacionadas ao tipo de dieta. A bacia do Rio Passa-Cinco, região centro-leste do Estado de São Paulo, é uma paisagem fortemente antropizada, com predomínio de pastagens, seguido por canaviais, reflorestamento de eucalipto e fragmentos de floresta estacional semidecídua. Realizamos levantamentos nesses habitats, determinando a riqueza de espécies e abundância relativa nas seguintes categorias tróficas de mamíferos de médio e grande porte: Insetívoros/Onívoros, Frugívoros/Onívoros, Frugívoros/Herbívoros, Carnívoros e Herbívoros/Pastadores. Diferenças quanto à riqueza de espécies e abundância relativa entre os habitats foram testadas com análise de variância de um fator, seguida pelo teste de Tukey, considerando: 1) cada categoria trófica separadamente e 2) o conjunto de todas as categorias tróficas. Entre julho de 2003 e junho de 2004 percorremos 284,4 km, registrando 20 espécies nativas e duas exóticas. Não foram detectadas diferenças na riqueza de espécies para nenhuma categoria trófica ou para a assembléia. Em relação à abundância relativa, a análise detectou diferenças para a assembléia como um todo, com as plantações de cana-de-açúcar apresentando maior abundância comparativamente as pastagens. Nossos resultados indicam que a paisagem heterogênea da área de estudo é dominada por espécies generalistas capazes de utilizar diversos tipos de habitats e itens alimentares disponíveis.

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The study of the influence of human hunting pressure on the social behavior of vertebrates requires a large background on both the hunting pressure and the social behavior of the species. Literature about this subject is relatively scarce. Most of the papers are restricted to shifts in demography, and are generally "species-specific". However, human hunting pressure cant not only affect demography but also some factors of the social behavior of a species such as parental care, territoriality, reproductive behavior, group-size, fraying behavior, mating system, and intraspecific competition. The presence of hunters in the area can lead the animals to move out of their original home-rangers. This can breakup the social structure and can cause long-term effects on the demography of hunted as well as nearby populations, amplifying the impact of hunting. On the other hand, harvest can be compensated in territorial species by "surplus population" of non-territorial individuals. Moreover, alternatively, an increase in the reproductive activity, as a response to hunting pressure, can compensate its effects in some species. Understanding the implications of hunting pressure in the social behavior of vertebrates might be decisive to the establishment of wildlife management and conservation programs. Manipulative experiments might help us to model such complex interactions. The occurrence of qualitative and quantitative changes in vertebrate social behavior directly or indirectly related to human hunting pressure is reviewed and analyzed in this paper.

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