948 resultados para Wildlife conservation.


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Deforestation in Brazilian Amazonia accounts for a disproportionate global scale fraction of both carbon emissions from biomass burning and biodiversity erosion through habitat loss. Here we use field- and remote-sensing data to examine the effects of private landholding size on the amount and type of forest cover retained within economically active rural properties in an aging southern Amazonian deforestation frontier. Data on both upland and riparian forest cover from a survey of 300 rural properties indicated that 49.4% (SD = 29.0%) of the total forest cover was maintained as of 2007. and that property size is a key regional-scale determinant of patterns of deforestation and land-use change. Small properties (<= 150 ha) retained a lower proportion of forest (20.7%, SD = 17.6) than did large properties (>150 ha; 55.6%, SD = 27.2). Generalized linear models showed that property size had a positive effect on remaining areas of both upland and total forest cover. Using a Landsat time-series, the age of first clear-cutting that could be mapped within the boundaries of each property had a negative effect on the proportion of upland, riparian, and total forest cover retained. Based on these data, we show contrasts in land-use strategies between smallholders and largeholders, as well as differences in compliance with legal requirements in relation to minimum forest cover set-asides within private landholdings. This suggests that property size structure must be explicitly considered in landscape-scale conservation planning initiatives guiding agro-pastoral frontier expansion into remaining areas of tropical forest. (C) 2010 Elsevier Ltd. All rights reserved.

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The use of scat surveys to obtain DNA has been well documented in temperate areas, where DNA preservation may be more effective than in tropical forests. Samples obtained in the tropics are often exposed to high humidity, warm temperatures, frequent rain and intense sunlight, all of which can rapidly degrade DNA. Despite these potential problems, we demonstrate successful mtDNA amplification and sequencing for faeces of carnivores collected in tropical conditions and quantify how sample condition and environmental variables influence the success of PCR amplification and species identification. Additionally, the feasibility of genotyping nuclear microsatellites from jaguar (Panthera onca) faeces was investigated. From October 2007 to December 2008, 93 faecal samples were collected in the southern Brazilian Amazon. A total of eight carnivore species was successfully identified from 71% of all samples obtained. Information theoretic analysis revealed that the number of PCR attempts before a successful sequence was an important negative predictor across all three responses (success of species identification, success of species identification from the first sequence and PCR amplification success), whereas the relative importance of the other three predictors (sample condition, season and distance from forest edge) varied between the three responses. Nuclear microsatellite amplification from jaguar faeces had lower success rates (15-44%) compared with those of the mtDNA marker. Our results show that DNA obtained from faecal samples works efficiently for carnivore species identification in the Amazon forest and also shows potential for nuclear DNA analysis, thus providing a valuable tool for genetic, ecological and conservation studies.

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In many mammals social organization promotes genetic structuring, which can be influenced by the dispersal pattern of the species. We analyzed the population genetic structure and dispersal of white-lipped peccaries (Tayassu pecan) from the Pantanal, Brazil. We genotyped 100 individuals at 7 microsatellite loci from 2 adjacent locations with no obvious geographic barrier between them. We found a significant but low F(ST) value, and the Bayesian analysis indicated a unique cluster. No significant differences were observed between mean assignment indices of resident males and females from both locations, and the probability of being born at the location sampled of > 30% of the individuals analyzed was lower than average. Mean relatedness between resident female, male, and opposite-sex pairs was not statistically different in both locations. These results suggest a low degree of genetic differentiation between the locations analyzed, and dispersal by both sexes (contrary to the predicted male-biased dispersal of most mammalian species).

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Doenças infecciosas em animais selvagens têm aumentado devido às alterações em seu habitat e ao maior contato com animais domésticos. A cinomose já foi descrita em diversas espécies de carnívoros selvagens, representando uma ameaça à conservação da vida selvagem. Nesse estudo é descrito o primeiro caso de infecção pelo vírus da cinomose em um furão (Galictis cuja). Um indivíduo de vida livre, sem sinais clínicos aparentes, apresentou morte súbita após um dia em cativeiro. Foi realizado o diagnóstico molecular para detecção do vírus da cinomose canina, sendo o resultado positivo. A filogenia do vírus indicou que cães domésticos foram a provável fonte de infecção.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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A caça e a pesca são exemplos clássicos de exploração de recursos naturais pelo homem, uma vez que estas atividades vêm sendo desenvolvidas desde a pré-história e, para algumas comunidades, continua sendo fonte de alimento tão importante quanto era para nossos antepassados. A pesca e outros produtos oriundos do extrativismo vegetal têm sido alvo constante de pesquisas para atender o mercado industrial, em detrimento dos estudos de etnoconservação. Em conseqüência desse desinteresse institucional e de outros fatores políticos intrínsecos, pouco se sabe sobre a biologia, a ecologia, a etologia e principalmente sobre a intensidade de exploração da fauna cinegética nos trópicos. Há uma grande lacuna sobre estudos que tratam da dieta de populações tradicionais na Amazônia, sobretudo aqueles que discorrem sobre a importância econômica e nutricional da atividade de caça e sua correlação com a conservação da vida silvestre. Este Estudo de Caso orientou-se para realizar a caracterização da fauna cinegética explorada por famílias extrativistas nas comunidades Aminã e Solimões na Reserva Extrativista do Tapajós/Arapiuns - PA, nas duas estações do ano (chuva e seca), além de revelar parâmetros nutricionais da atividade de caça na dieta protéica daquelas famílias. Os dados de abundância relativa (biomassa) para as espécies registrada nas duas comunidades estudadas mostram que Dasyprocta leporina (cutia) se revelou como a espécie mais pressionada. Quando comparados os Índice de Biomassa (IB) entre as fontes de proteínas animal e entre as comunidades estudadas, concluiu-se que a carne de caça, apesar de ser menos freqüente em termos de dias de consumo em relação ao pescado, as refeições realizadas com carne de caça são mais fartas do que as refeições realizadas com peixe. Além disso, com relação ao Índice de Proteína (IP), quando comparado entre fontes critérios e parâmetros para a implementação de projetos de manejo integrado de fauna em ocupações humanas.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The policy of the Cape Provincial Department of Nature Conservation is based on the concept of "wise management" of wildlife resources. Where crop damage is real, control measures are essential. These, however, must be adapted to the species concerned and applied only where the damage is taking place. Blanket measures which also kill many useful species must be avoided. For this reason, the control of problem animals should be vested in the agency concerned with wildlife conservation.

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Wildlife Damage Conferences: When, Where, and Why? -- Robert M. Timm, Editor, THE PROBE Booklet Review:"The Problem with Skunks!!" by Edward Kellems (34 pages, illustrated. $14.95) New NWCO Web Page url is http://www.wildlifedamagecontrol.com/nwcoa.htm Abstracts from the 2nd International Wildlife Management Congress, Hungary Human Disturbance as a Design Factor to Aid Displacement of Canada Geese from Urban Parks -- P. C. Whitford, Biology Department, Capital University, Columbus, OH Leopard Problems in Nepal -- T. M. Maskey, National Parks and Wildlife Conservation Department, Kathmandu, Nepal Elk-human Conflict Management in Banff National Park, Alberta, Canada -- J. A. McKenzie, Banff National Park Wildlife Laboratory The Avoidance of Virtual Barriers by Wolves in Captivity -- M. Musiani*, E. Visalberghi*, andL. Boitani, *CNR Psychology Institute, Rome, Italy Successful Field Trials of a New Slow-Release Capsaicin-Based Animal Repellent for Reducing a Variety of Human-Wildlife Conflicts in Israel -- S. C. Nemtzov, Dept. of Terrestrial Ecology, The Nature and National Parks Protection Authority, Jerusalem, Israel Educational Workshops: A Proactive Approach to Conflict Resolution in Wildlife Management -- K. B. Reis, H. R. Campa III, R. B. Peyton, and S. Winterstein, Dept. of Fisheries & Wildlife, Michigan State University, East Lansing, MI Traps and Trapping in Sweden -- T. Svensson, Swedish Environmental Protection Agency, Stockholm, Sweden Actual Problems of Predator Management in Hungary -- L. Szemethy, M. Heltai, and Z. Biro, Dept. of Wildlife Biology & Management, Godollo University of Agricultural Sciences, Godollo, Hungary Crop and Livestock Depredation by Wildlife -- N. Udaya Sekhar, Centre for Int'I. Environment & Development Studies, Aas, Norway Conservation of the Iberian Wolf in Portugal—The Everlasting Conflict with Man -- J. V. Vingada*, C. Eira, S. Scheich, C. Fonseca, M. Soares, F. L. Correia, M. Fana* P. Carmo, A. Ferreira, A. Soares, and B. Bobek. *Dept. deBiologia da Universidade do Minho, Campus de Gualtar, Portugal Barkpeeling Damage in Relation to Red Deer Density and Forest Structure in Austria -- F. H. Voelk, Institute of Wildlife Biology & Game Management, Universitaetfuer Bodenkultur Wien, Vienna, Austria Human-Wildlife Conflict Resolution: National Imperatives and Strategies -- P. 0. Wander a Kenya Wildlife Service, Nairobi, Kenya An Overview and Evaluation of Deer Herd Management Programs in Urban and Suburban Communities of the USA -- R. J. Warren, Warnell School of Forest Resources, Univ. of Georgia, Athens, GA

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Aboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: 1. What is the best H-model form and geographic unit to include in biomass models to minimise site-level uncertainty in estimates of destructive biomass? 2. To what extent does including H estimates derived in (1) reduce uncertainty in biomass estimates across all 327 plots? 3. What effect does accounting for H have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of destructively harvested trees when including H (mean 0.06), was half that when excluding H (mean 0.13). Power- and Weibull-H models provided the greatest reduction in uncertainty, with regional Weibull-H models preferred because they reduce uncertainty in smaller-diameter classes (< 40 cm D) that store about one-third of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows that including H reduces errors from 41.8 Mg ha(-1) (range 6.6 to 112.4) to 8.0 Mg ha(-1) (-2.5 to 23.0).

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Clyomys Thomas, 1916 is a semifossorial rodent genus of spiny rats represented by only one species, C. laticeps, which inhabits the tropical savannas and grasslands of central Brazil and eastern Paraguay. Here we describe a new karyotype of C. laticeps found in populations of Emas National Park, Goias state, Brazil. The four analyzed specimens had a diploid number (2n) of 32 and a fundamental autosome number (FN) of 54. Cytogenetic data include conventional staining, CBG and GTG-banding. The karyotype presents 12 meta/submetacentric pairs (1 to 12) and 3 pairs of acrocentrics (13 to 15) with gradual decrease in size. The X chromosome is a medium submetacentric and the Y is a medium acrocentric. The semifossorial habits together with habitat specificity could have contributed to the karyological variations found on this genus.

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The gecko genus Phyllopezus occurs across South America's open biomes: Cerrado, Seasonally Dry Tropical Forests (SDTF, including Caatinga), and Chaco. We generated a multi-gene dataset and estimated phylogenetic relationships among described Phyllopezus taxa and related species. We included exemplars from both described Phyllopezus pollicaris subspecies, P. p. pollicaris and P. p. przewalskii. Phylogenies from the concatenated data as well as species trees constructed from individual gene trees were largely congruent. All phylogeny reconstruction methods showed Bogertia lutzae as the sister species of Phyllopezus maranjonensis, rendering Phyllopezus paraphyletic. We synonymized the monotypic genus Bogertia with Phyllopezus to maintain a taxonomy that is isomorphic with phylogenetic history. We recovered multiple, deeply divergent, cryptic lineages within P. pollicaris. These cryptic lineages possessed mtDNA distances equivalent to distances among other gekkotan sister taxa. Described P. pollicaris subspecies are not reciprocally monophyletic and current subspecific taxonomy does not accurately reflect evolutionary relationships among cryptic lineages. We highlight the conservation significance of these results in light of the ongoing habitat loss in South America's open biomes. (C) 2011 Elsevier Inc. All rights reserved.

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The presence of Toxoplasma gondii and Leptospira spp. antibodies was investigated in 74 manatees (Trichechus inunguis [Mammalia: Sirenia]) kept in captivity in two rescue units in the northern region of Brazil. Antibodies to T gondii were detected in 29 (39.2%) of 74 animals by using the modified agglutination test (titer, 1:25). For antibodies against Leptospira spp., sera were diluted 1:50 and tested against 24 strains of leptospires by microscopic agglutination microtechnique, and positive samples were end titrated. Twenty-three (31.1%) of 74 animals were reactive to four serovars (Patoc 21/23, Castellonis 2/23, Icterohaemorrhagiae 1/23, and Butembo 1/23), with titers ranging from 100 to 1,600. This is the first report of antibodies against T gondii and Leptospira spp. in T. inunguis from the Brazilian Amazon.

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The effects of habitat configuration on species persistence are predicted to be most apparent when remaining habitat cover is below 30%. We tested this prediction by comparing vertebrate communities in 21 landscapes located in the southern Amazonia, including 7 control landscapes (similar to 100% of forest cover) and 14 fragmented landscapes (4 x 4 km). The fragmented landscapes retained similar proportions of forest (similar to 25%), but had contrasting configurations, resulting from two different deforestation patterns: the "fish-bone pattern" common in small properties, and the large-property pattern generally used by large ranchers. Vertebrates were surveyed in all landscapes in February-July 2009 with interviews (n = 150). We found a significant difference in reported species richness among the fish-bone, large-property, and control areas (mean = 29.3, 38.8 and 43.5 respectively). Control areas and large-properties tended to have a higher number of specialist species (mean = 13.7, and 11.7, respectively), when compared with the fish-bone pattern (5.1). Vertebrate community composition in the control and large-properties was more similar to one another than to those of the fish-bone landscapes. The number of fragments was the main factor affecting the persistence of species, being negatively associated with specialist species richness. Species richness was also positively related with the size of the largest fragment structurally connected to the studied landscapes (i.e., a regional scale effect). Our results demonstrated that the large-property pattern, which results in less fragmented landscapes, can maintain a more diverse community of large vertebrates, including top predators, which are considered fundamental for maintaining ecosystem integrity. These results support the hypothesis that landscape configuration contributes to the persistence and/or extirpation of species.