Leandro Silveira

Universidade Federal do Rio Grande do Sul, Pôrto de São Francisco dos Casaes, Rio Grande do Sul, Brazil

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Publications (56)80.96 Total impact

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    ABSTRACT: The global population of jaguars Panthera onca has decreased significantly since the beginning of the 20th century. Given the scarcity of demographic and biological information, estimating population parameters is critical for the design of conservation measures. The jaguar’s elusive behaviour makes it impossible to estimate and monitor populations by direct observation. We propose a noninvasive genetic sampling approach and demonstrate its potential for large-scale monitoring. Sex identification was optimized for faecal samples of jaguars and other felids. We also optimized a set of 11 microsatellite markers for reliable identification of individuals. We estimated the effectiveness of faecal sample genotyping in two distinct Brazilian biomes: the Pantanal and the semi-arid Caatinga. Almost 90% of the samples that were molecularly identified as jaguar (n590) were successfully genotyped and were assigned to 30 individuals. Genetic diversity was generally high but was significantly lower in the Caatinga population. We show that non-invasive genetic sampling can be a reliable tool to study population parameters and to monitor the genetic status of jaguar populations in different habitats. It may also be useful for future surveys of jaguars that address ecological, behavioural and conservation issues, and could provide a baseline for non-invasive genetic studies of other wild felid populations.
    Oryx 01/2014; · 1.62 Impact Factor
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    ABSTRACT: Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations [1-9]. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south.
    Current biology: CB 11/2013; · 10.99 Impact Factor
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    ABSTRACT: The modeling of top predators' habitats and the understanding of their environmental requirements in landscapes facing high land-use transformation pressure have long-standing importance for the development of conservation strategies. Multi-distance spatial cluster analysis and logistic regression with environmental weighting for pseudo-absence designation were applied to understand spatial patterns of jaguar occurrence in Mato Grosso state (Central Western Brazil). This location has been under intense deforestation pressure since the 1970s and is historically one of the most important jaguar habitats in the world. By using a model of five independent variables, we were able to achieve a 73.2 percent success rate of case/non-case classification and indicate not only a general loss of habitat suitability, but also an increasing interruption of potential migration corridors in the state. Our analysis on a regional scale demonstrates the importance of forest and savannah woodland for jaguar habitat maintenance in the Mato Grosso state. The jaguar species demonstrates a sensitivity to landscape fragmentation, which can be parameterized for improved model building by metrics such as edge density and patch size. Comparisons with previous studies in South America show that parameter selection for jaguar habitat modeling is highly scale-dependent and that habitat suitability in partially transformed landscapes could be maintained if fragmentation is minimized. Recent land-use transformation, however, has significantly weakened the conservation status of the Pantanal-Amazon corridor. Resumo A modelagem de habitats de predadores topo de cadeia e o entendimento de seus requerimentos ambientais em paisagens sob intensa pressão de uso da terra possuem importância crucial para o desenvolvimento de estratégias de conservação. Neste estudo, foi realizada uma análise de agrupamento de distância múltipla e regressões logísticas para entender os padrões espaciais de ocorrência da onça-pintada no estado de Mato Grosso (Oeste do Brasil Central). Essa região encontra-se sob intensa pressão de desmatamento desde os anos 70 e consiste historicamente em um dos principais habitats para a espécie no país. Utilizando um modelo de cinco variáveis independentes, foi alcançado um acerto geral de 73.2% para uma classificação binária. Os resultados obtidos não somente indicam uma perda geral da adequabilidade de habitat, mas também uma sucessiva interrupção dos potenciais corredores de migração no Mato Grosso. A espécie apresentou uma sensibilidade à fragmentação da paisagem, que pode ser parametrizada para melhorar o desempenho do modelo, por métricas da paisagem, tais como tamanho de fragmentos e densidade de bordas. Comparações com estudos prévios na America Latina mostram que a seleção de parâmetros para modelagem de habitat da onça-pintada é altamente dependente da escala projetada e que a aptidão do habitat em paisagens transformadas pode ser assegurada se a fragmentação for reduzida. As transformações recentes do uso e ocupação da terra, porém, enfraqueceram significativamente o status de conservação do corredor Pantanal-Amazônia.
    Biotropica 11/2013; · 2.35 Impact Factor
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    ABSTRACT: We investigated the exposure of jaguar (Panthera onca) populations and domestic carnivores to selected viral infections in the Cerrado, Amazon, and Pantanal biomes of Brazil. Between February 2000 and January 2010, we collected serum samples from 31 jaguars, 174 dogs (Canis lupus familiaris), and 35 domestic cats (Felis catus). Serologic analyses for antibodies to rabies virus, canine distemper virus (CDV), feline immunodeficiency virus (FIV), and for feline leukemia virus (FeLV) antigen were conducted. The jaguars from Cerrado and Pantantal were exposed to rabies virus, while the jaguars from the Pantanal and the dogs from all three areas were exposed to CDV. Two cats from the Amazonian site were antigen-positive for FeLV, but no jaguars had FeLV antigen or FIV antibody. Canine distemper and rabies viruses should be carefully monitored and considered potential threats to these jaguar populations. Currently FIV and FeLV do not appear to represent a health threat for jaguar populations in this area. Domestic dogs and cats in these areas should be vaccinated, and the movement of domestic animals around protected areas should be restricted.
    Journal of wildlife diseases 07/2013; 49(3):510-21. · 1.27 Impact Factor
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    ABSTRACT: Diet of the jaguar Panthera onca in the Cerrado, central Brazil, was investigated based on a sample of genetically identified jaguar scats. At least nine prey species were observed in 35 scat samples. Giant anteaters Myrmecophaga tridactyla contributed more than 75 % of biomass to the observed diet. Tapirs Tapirus terrestris and peccaries Tayassu pecari and Pecari tajacu contributed approximately 6 % to jaguar diet each, and small mammals contributed least to the jaguar diet. At 0.121, dietary niche breadth was narrower than reported in most other studies. Due to their physical characteristics and abundance, giant anteaters are likely the most profitable prey for jaguars in Emas National Park, and as an important prey, they should be included in jaguar conservation efforts.
    European Journal of Wildlife Research 03/2013; 59:445-448. · 1.36 Impact Factor
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    ABSTRACT: White-lipped peccaries (Tayassu pecari) are important seed predators and dispersers throughout the Neotropics. Because they occur in groups as large as 300 individuals, they need large areas to persist. We investigated home-range size and overlap of 13 groups using radiotelemetry data from 3 years of monitoring in the Emas National Park and surrounding farmland in central Brazil. Average home-range sizes were 1,710.64 ha for 50% of the locations and 8,659.99 ha for 95% based on minimum convex polygons and 790.38 ha for 50% of the locations and 7,986.92 ha for 95% based on the fixed kernel estimator. Home-range size did not correlate with group size, the monitoring period, or the number of locations obtained. Home ranges were larger during the wet season than the dry season. Average home-range overlap among groups was 31%; there were no significant differences in overlap between seasons. Home ranges varied seasonally, most likely in response to the dynamic landscape of crop plantations surrounding the park. Although the peccaries fared well in the heterogeneous agricultural landscape surrounding the park, conflict with farmers due to crop damage and landscape changes due to expansion of sugarcane plantations need to be addressed by conservation strategies.
    Journal of Mammalogy 01/2013; 94(1):137-145. · 2.31 Impact Factor
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    ABSTRACT: Jaguars (Panthera onca) and pumas (Puma concolor) coexist throughout the Neotropics. Using camera trapping in four Brazilian biomes, we compare the daily activity patterns of the jaguar and puma, and their relationships with their main prey species. We used a kernel density method to quantify daily activity patterns and to investigate overlap between these predators and their main prey. Both cats showed intensive nocturnal and crepuscular activity (0.69 and 0.14 kernel density, respectively, for jaguars; 0.68 and 0.19 kernel density, respectively, for pumas). Only in the Pantanal did we observe a pattern of concentrated diurnal activity for both species. We found little temporal segregation between jaguars and pumas, as they showed similar activity patterns with high coefficients of overlapping (average ∆1 = 0.86; SE = 0.15). We also observed a significant overlap between the activity patterns of the predators and their main prey species, suggesting that both predators adjust their activity to reduce their foraging energy expenditure. Our findings suggest that temporal partitioning is probably not a generalized mechanism of coexistence between jaguars and pumas; instead, the partitioning of habitat/space use and food resources may play a larger role in mediating top predator coexistence. Knowledge about these behavior aspects is crucial to elucidating the factors that enable coexistence of jaguars and pumas. Furthermore, an understanding of their respective activity periods is relevant to management and associated research efforts. Resumo Onças-pintadas (Panthera onca) e onças-pardas coexistem em todo o Neotrópico. Embora existam vários estudos sobre a coexistência dessas duas espécies, somente alguns investigam o padrão de atividade temporal entre biomas. Usando armadilhas fotográficas em quatro biomas Brasileiros comparamos o padrão de atividade diário de pintadas e pardas, e a relação com suas principais espécies presa. Usamos o método de densidade Kernel para quantificar o padrão de atividade diária e investigar a sobreposição entre estes predadores e suas principais presas. As duas espécies apresentam uma intensa atividade noturna e crepuscular (0.69 e 0.14 de densidade kernel, respectivamente para pintadas; 0.68 e 0.19 de densidade kernel, respectivamente para pardas). Somente no Pantanal observamos um maior patrão de atividade diurno para ambas as espécies. Verificamos pouca segregação temporal entre onças pintadas e pardas, uma vez que demonstraram similar atividade com altos coeficientes de sobreposição (média ∆1 = 0.86; SE = 0.15). Também observamos uma significante sobreposição entre o padrão de atividade destes predadores e suas principais espécies presa, sugerindo que ambos ajustam suas atividades para reduzir o gasto energético no forrageamento. Nossos resultados sugerem que provavelmente o particionamento temporal não é um mecanismo generalizado de coexistência entre onças pintadas e pardas; em alternativa a segregação do uso do habitat/espaço e de recursos alimentares podem desempenhar um papel mais importante na mediação da coexistência entre esses predadores topo nessas áreas. O conhecimento sobre estes aspectos comportamentais é fundamental para elucidar os fatores que permitem a coexistência entre onças-pintadas e onças-pardas. Por fim, compreender o padrão de atividade das espécies é relevante para sua gestão e esforços de pesquisa.
    Biotropica 01/2013; · 2.35 Impact Factor
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    ABSTRACT: Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations [1–9]. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of ti-grina (L. tigrinus), leading to remarkable cytonuclear discor-dance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, lead-ing us to support their formal recognition as distinct spe-cies, namely L. tigrinus in the northeast and L. guttulus in the south.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations [1–9]. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of ti-grina (L. tigrinus), leading to remarkable cytonuclear discor-dance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, lead-ing us to support their formal recognition as distinct spe-cies, namely L. tigrinus in the northeast and L. guttulus in the south.
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    ABSTRACT: Faeces provide relevant biological information which includes, with the application of genetic techniques, the sex and identity of individuals that defecated, thus providing potentially useful data on the behaviour and ecology of individuals, as well as the dynamics and structure of populations. This paper presents estimates of the sex ratio of different felid species (jaguar, Panthera onca; puma, Puma concolor; and ocelot/margay, Leopardus pardalis/Leopardus wiedi) as observed in field collected faeces, and proposes several hypotheses that could explain the strikingly high proportion of faeces from male jaguars. The proportion of male and female faeces was estimated using a non-invasive faecal sampling method in 14 study areas in Mexico and Brazil. Faecal samples were genetically analysed to identify the species, the sex and the individual (the latter only for samples identified as belonging to jaguars). Considering the three species, 72.6% of faeces (n = 493) were from males; however, there were significant differences among them, with the proportion from males being higher for jaguars than for pumas and ocelots/margays. A male-bias was consistently observed in all study areas for jaguar faeces, but not for the other species. For jaguars the trend was the same when considering the number of individuals identified (n = 68), with an average of 4.2±0.56 faeces per male and 2.0±0.36 per female. The observed faecal marking patterns might be related to the behaviour of female jaguars directed toward protecting litters from males, and in both male and female pumas, to prevent interspecific aggressions from male jaguars. The hypothesis that there are effectively more males than females in jaguar populations cannot be discarded, which could be due to the fact that females are territorial and males are not, or a tendency for males to disperse into suboptimal areas for the species.
    PLoS ONE 01/2012; 7(12):e52923. · 3.53 Impact Factor
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    ABSTRACT: Camera trapping has become a popular tech-nique to monitor carnivore populations due to its use-fulness in estimating abundance. Nevertheless, there are a number of problems associated with study design which are motivating researchers to search for a com-promise that ensures improvement of precision while being cost-effective. We have used data from a capture– recapture study in a forested area in central Brazil to evaluate the effectiveness of using one versus two cam-eras per trapping station for determining jaguar (Pan-thera onca) density and capture rates of several other mammals. The capture rate for the jaguar and other species recorded with only one camera was lower than that with two cameras. The number of jaguars identified using photos from one camera ranged between six and seven animals, but reached ten individuals when two-camera sets were used where pictures of both flanks could be positively individualized. These differences, combined with different estimates of effective sampled area size, resulted in jaguar densities estimates ranging from 2.18 to 5.40 and 3.99 individuals/100 km 2 when one and two cameras were used per station, respectively (using the half-MMDM and Heterogeneity model). Based on our results, we recommend the use of two cameras per station for jaguar density monitoring to ensure reasonable levels of reliability and accuracy of estimates despite a small sample size.
    Ecological Research 01/2012; · 1.55 Impact Factor
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    ABSTRACT: Coexistence of sympatric species is mediated by resource partitioning. Pumas occur sympatrically with jaguars throughout most of the jaguar's range but few studies have investigated space partitioning between both species. Here, camera trapping and occupancy models accounting for imperfect detection were employed in a Bayesian framework to investigate space partitioning between the jaguar and puma in Emas National Park (ENP), central Brazil. Jaguars were estimated to occupy 54.1% and pumas 39.3% of the sample sites. Jaguar occupancy was negatively correlated with distance to water and positively correlated with the amount of dense habitat surrounding the camera trap. Puma occupancy only showed a weak negative correlation with distance to water and with jaguar presence. Both species were less often present at the same site than expected under independent distributions. Jaguars had a significantly higher detection probability at cameras on roads than at off-road locations. For pumas, detection was similar on and off-road. Results indicate that both differences in habitat use and active avoidance shape space partitioning between jaguars and pumas in ENP. Considering its size, the jaguar is likely the competitively dominant of the two species. Owing to its habitat preferences, suitable jaguar habitat outside the park is probably sparse. Consequently, the jaguar population is likely largely confined to the park, while the puma population is known to extend into ENP's surroundings.
    Mammalian Biology - Zeitschrift fur Saugetierkunde 01/2012; 77:41-46. · 1.25 Impact Factor
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    ABSTRACT: Aim: To test the prediction that environmental suitability derived from species distribution modelling (SDM) could be a surrogate for jaguar local population density estimates. Location: Americas. Methods: We used 1409 occurrence records of jaguars to model the distribution of the species using 11 SDM methods. We tested whether models' suitability is linearly correlated with jaguar population densities estimated from 37 different locations. We evaluated whether the relationship between density and suitability forms a constraint envelope, in which higher densities are found mainly in regions with high suitability, whereas low densities can occur in regions with variable suitability. We tested this using heteroscedasticity test and quantile regressions. Results: A positive linear relationship between suitability and jaguar density was found only for four methods [bioclimatic envelope (BIOCLIM), genetic algorithm for rule set production (GARP), maximum entropy (Maxent) and generalized boosting models (GBM)], but with weak explanatory power. BIOCLIM showed the strongest relationship. Variance of suitability for lower densities values was larger than for higher values for many of the SDM models used, but the quantile regression was significantly positive only for BIOCLIM and random forests (RF). RF and GBM provided the most accurate models when measured with the standard SDM evaluation metrics, but possess poor relationship with local density estimates. Main conclusions: Results indicate that the relationship between density and suitability could be better described as a triangular constraint envelope than by a straight positive relationship, and some of the SDM methods tested here were able to discriminate regions with high or low local population densities. Low jaguar densities can occur in areas with low or high suitability, whereas high values are restricted to areas where the suitability is greater. In high suitability areas but with low jaguar density estimates, we discuss how extrinsic factors driving abundance could act at local scales and then prevent higher densities that would be expected by the favourable regional environmental conditions.
    Diversity and Distributions 01/2012; 18(5):615-627. · 6.12 Impact Factor
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    Aquatic Mammals 01/2011; 37(2):208-212. · 0.70 Impact Factor
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    ABSTRACT: Due to the advancing agricultural frontier in the Brazilian Amazon, the present rate of deforestation engenders a pessimistic scenario for vertebrate diversity in the area. Protected areas are an essential conservation tool to limit biodiversity loss, but their efficiency have yet to be proven. Here, we used camera-trap data on the presence of medium and large-size vertebrates in a protected area (Cantão State Park) and a neighbouring private forest reserve (Santa Fé Ranch) to evaluate their effectiveness in protecting biodiversity. We also gathered information on seasonality and activity patterns. A total sampling effort of 7929 trap-nights revealed a diverse vertebrate fauna in the region. A total of 34 mammal species, belonging to 8 different orders was detected in the study area, some of which have a high level of conservation interest and value. The photographic index showed that diversity was more abundant outside the protected area of Cantão State Park, where seasonality could play a major role in vertebrate occurrence. Overall, the influence of seasonality on distribution appears to be species-specific. During the wet season around 40% of the common species were not detected inside the park, whereas in Santa Fé Ranch most species (62.5%) suffered only a slight decrease in relative abundance probably due to changes in the availability of food resources. Our results highlight the importance of private land for vertebrate conservation in the Amazon and alert to the need for increased law enforcement in these areas to secure biodiversity preservation. KeywordsCamera-trapping–Tropical mammals and birds–Amazon–Activity period
    Biodiversity and Conservation 01/2011; 20(3):505-518. · 2.26 Impact Factor
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    ABSTRACT: Conserving animals beyond protected areas is critical because even the largest reserves may be too small to maintain viable populations for many wide-ranging species. Identification of landscape features that will promote persistence of a diverse array of species is a high priority, particularly, for protected areas that reside in regions of otherwise extensive habitat loss. This is the case for Emas National Park, a small but important protected area located in the Brazilian Cerrado, the world's most biologically diverse savanna. Emas Park is a large-mammal global conservation priority area but is too small to protect wide-ranging mammals for the long-term and conserving these populations will depend on the landscape surrounding the park. We employed novel, noninvasive methods to determine the relative importance of resources found within the park, as well as identify landscape features that promote persistence of wide-ranging mammals outside reserve borders. We used scat detection dogs to survey for five large mammals of conservation concern: giant armadillo (Priodontes maximus), giant anteater (Myrmecophaga tridactyla), maned wolf (Chrysocyon brachyurus), jaguar (Panthera onca), and puma (Puma concolor). We estimated resource selection probability functions for each species from 1,572 scat locations and 434 giant armadillo burrow locations. Results indicate that giant armadillos and jaguars are highly selective of natural habitats, which makes both species sensitive to landscape change from agricultural development. Due to the high amount of such development outside of the Emas Park boundary, the park provides rare resource conditions that are particularly important for these two species. We also reveal that both woodland and forest vegetation remnants enable use of the agricultural landscape as a whole for maned wolves, pumas, and giant anteaters. We identify those features and their landscape compositions that should be prioritized for conservation, arguing that a multi-faceted approach is required to protect these species.
    PLoS ONE 01/2011; 6(12):e28939. · 3.53 Impact Factor
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    ABSTRACT: Owing to habitat conversion and conflict with humans, many carnivores are of conservation concern. Because of their elusive nature, camera trapping is a standard tool for studying carnivores. In many vertebrates, sex-specific differences in movements – and therefore detection by cameras – are likely. We used camera trapping data and spatially explicit sex-specific capture–recapture models to estimate jaguar density in Emas National Park in the central Brazilian Cerrado grassland, an ecological hotspot of international importance. Our spatially explicit model considered differences in movements and trap encounter rate between genders and the location of camera traps (on/off road). We compared results with estimates from a sex-specific non-spatial capture–recapture model. The spatial model estimated a density of 0.29 jaguars 100km−2 and showed that males moved larger distances and had higher trap encounter rates than females. Encounter rates with off-road traps were one tenth of those for on-road traps. In the non-spatial model, males had a higher capture probability than females; density was estimated at 0.62 individuals 100km−2. The non-spatial model likely overestimated density because it did not adequately account for animal movements. The spatial model probably underestimated density because it assumed a uniform distribution of jaguars within and outside the reserve. Overall, the spatial model is preferable because it explicitly considers animal movements and allows incorporating site-specific and individual covariates. With both methods, jaguar density was lower than reported from most other study sites. For rare species such as grassland jaguars, spatially explicit capture–recapture models present an important advance for informed conservation planning.
    Biological Conservation 01/2011; 144(3):1017-1024. · 3.79 Impact Factor
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    ABSTRACT: ABSTRACT  The maned wolf (Chrysocyon brachyurus) inhabits the savannah-like Cerrado of Brazil. Although 80% of this biome has already been affected by human activity, little is known about maned wolf abundance. Using mark—recapture models, we obtained the first density estimate from central Brazil, the core of maned wolf distribution. With 5.19 individuals/100 km2, even large reserves support only small maned wolf populations. Therefore, long-term conservation of the maned wolf depends on land management outside of reserves.
    Journal of Wildlife Management 12/2010; 73(1):68 - 71. · 1.64 Impact Factor
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    ABSTRACT: Rabies virus is a pathogen of major concern in free-ranging wild carnivores in several regions of the world, but little is known about its circulation in Brazilian wild carnivores. Sera from 211 free-ranging wild carnivores, captured from 2000 to 2006 in four locations of two Brazilian biomes (Pantanal and Cerrado), were tested for rabies antibodies. Twenty-six individuals (12.3%) had neutralizing antibody titers ≥0.10 IU/ml. The four sampled locations had antibody-positive animals, suggesting that Rabies virus circulates in all of these regions. Results underscore the risk posed by rabies for conservation of Brazilian carnivores and the possibility of the animals acting as reservoirs for the Rabies virus.
    Journal of wildlife diseases 10/2010; 46(4):1310-5. · 1.27 Impact Factor
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    ABSTRACT: Most protected areas are too small to sustain populations of wide-ranging mammals; thus, identification and conservation of high-quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area. We determined the effectiveness of scat-detection dogs in detecting presence of five species of mammals threatened with extinction by habitat loss: maned wolf (Chrysocyon brachyurus), puma (Puma concolor), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), and giant armadillo (Priodontes maximus). The probability of scat detection varied among the five species and among survey quadrats of different size, but was consistent across team, season, and year. The probability of occurrence, determined from the presence of scat, in a randomly selected site within the study area ranged from 0.14 for jaguars, which occur primarily in the forested areas of the park, to 0.91 for maned wolves, the most widely distributed species in our study area. Most occurrences of giant armadillos in the park were in open grasslands, but in the agricultural matrix they tended to occur in riparian woodlands. At least one target species occurred in every survey quadrat, and giant armadillos, jaguars, and maned wolves were more likely to be present in quadrats located inside than outside the park. The effort required for detection of scats was highest for the two felids. We were able to detect the presence for each of five wide-ranging species inside and outside the park and to assign occurrence probabilities to specific survey sites. Thus, scat dogs provide an effective survey tool for rare species even when accurate detection likelihoods are required. We believe the way we used scat-detection dogs to determine the presence of species can be applied to the detection of other mammalian species in other ecosystems.
    Conservation Biology 10/2010; 25(1):154-62. · 4.36 Impact Factor

Publication Stats

345 Citations
80.96 Total Impact Points

Institutions

  • 2013
    • Universidade Federal do Rio Grande do Sul
      • Departamento de Genética
      Pôrto de São Francisco dos Casaes, Rio Grande do Sul, Brazil
  • 2006–2013
    • Jaguar Conservation Fund (JCF)
      Mineiros, Goiás, Brazil
    • Universidade Estadual de Goiás
      Morrinhos, Goiás, Brazil
  • 2008–2010
    • CEP America
      Emeryville, California, United States
  • 1999–2010
    • Universidade Federal de Goiás
      • Departamento de Biologia Geral
      Goianá, Goiás, Brazil