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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An?lises ecol?gicas de duas esp?cies de fel?deos (Leopardus geoffroyi e L. colocolo) em ?reas antropizadas da Savana Uruguaia

Tirelli, Fl?via Pereira 29 March 2017 (has links)
Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2017-11-16T18:24:38Z No. of bitstreams: 1 Tese_de_doutorado_Tirelli, Fl?via.pdf: 5027623 bytes, checksum: 81a5590c184505adcd79dad015861356 (MD5) / Rejected by Caroline Xavier (caroline.xavier@pucrs.br), reason: Devolvido devido ? falta de capa institucional no arquivo PDF. on 2017-11-22T18:49:41Z (GMT) / Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2017-11-27T12:18:11Z No. of bitstreams: 1 Tese_de_doutorado_Tirelli_Fl?via.pdf: 5108938 bytes, checksum: 3109955638e7a5001b25fd2a66f33aaf (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-12-04T12:20:18Z (GMT) No. of bitstreams: 1 Tese_de_doutorado_Tirelli_Fl?via.pdf: 5108938 bytes, checksum: 3109955638e7a5001b25fd2a66f33aaf (MD5) / Made available in DSpace on 2017-12-04T12:27:17Z (GMT). No. of bitstreams: 1 Tese_de_doutorado_Tirelli_Fl?via.pdf: 5108938 bytes, checksum: 3109955638e7a5001b25fd2a66f33aaf (MD5) Previous issue date: 2017-03-29 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The Geoffroy?s cat (Leopardus geoffroyi) and the pampas cat (L. colocolo) are small Neotropical felids that typically occur in open landscapes. These species are distributed simpatricaly in the Uruguayan Savannah ecoregion. In this region, Geoffroy?s cat and pampas cat are considered, respectively, to be abundant and rare species. The present study aimed to evaluate these propositions and to characterize ecological aspects of these species in this threatened ecoregion. The study was conducted from November 2013 to September 2015 in privately owned areas in ?Serra do Caver??, southernmost Brazil. We installed and monitored 26 camera-traps and we performed eight capture campaigns aiming to fit individuals of both species with VHF radio-collars and to collect blood samples. As a result, we obtained 516 image records of Geoffroy?s cat and captured 12 different individuals of same species, seven of which were monitored by radio-telemetry. We did not find any record of pampas cat, which demonstrated the rareness or absence of the species in the study area. From the Geoffroy?s cat data, we observed that males had home-range (HR), core-area and body weight that were larger than those of females. We also observed that male body weight significantly and positively influenced HR size, whereas in females such relationship was not significant. We observed extensive HR and core area overlap, with minor changes in overlap between seasonal partitions. These results indicate some degree of sociability in this population. Interestingly, our kinship analyses indicated that the majority of the cats sampled in this population were unrelated, and that genetic relatedness did not significantly influence the levels of HR and core area overlap. This indicated that the population, in the studied scale, has a socio-spatial structure that departs from what could be expected based on a model assuming male dispersal and female philopatry. Additionally to the socio-spatial patterns, we also investigated factors that influence the persistence of the species in the threatened Uruguayan Savannah. We observed that this population significantly selected riparian vegetation and avoided open grassland with cattle. It is noteworthy that the protection of riparian vegetation is required by Brazilian national law. Hence, this habitat may provide shelter for Geoffroy?s cats, and hypothetically it could serve as an ecological corridor for the species, an important issue that should be tested deepened in the future. This population also presented significantly nocturnal activity patterns, which consequently avoids human contact. The density estimation was considered reasonable in comparison to other areas within the Geoffroy?s cat range, agreeing with the initial estimate for the species in the region. In these studies, we obtained insights that help us understand some ecological characteristics of the species, and to assess the bases for its persistence in these human-dominated landscapes. Such insights could not be obtained for the pampas cat, as it seems to be currently absent from the study site. Its absence or rarity at this site and several others within the ecoregion is a worrisome observation, from a conservation perspective. This is especially the case given that the Uruguayan Savannah contains a distinct ?Evolutionarily Significant Unit? (ESU) of pampas cats. Therefore, in the fourth chapter, we aimed to assess the current spatial distribution and conservation status of the pampas cat in the Uruguayan Savannah. We collected 107 spatial records and constructed two models (with and without anthropogenic variables), each of them built separately with two different algorithms (Maxent and Maxlike). All models were very similar, indicating higher suitability (or probability of occurrence [PO]) in grassland areas from sea level to 400m of altitude. The best-fit models were those including anthropogenic variables, which also yielded a more restricted distribution of higher suitability and higher PO areas, supporting the conclusion that this pampas cat population is affected by human disturbance. The estimation of the population size for high-suitability and high-PO areas resulted in assignment to the ?Critically Endangered? and ?Endangered? categories, respectively. Based on these results, we highlight the urgent need for conservation plans targeting pampas cats in the Uruguayan Savannah. In the global study, we observed that similar felid species seem to respond differently to human impacts, and obtained results that can contribute to the design of conservation actions aiming to ensure the long-term survival of these two species in this threatened ecoregion. / As esp?cies Leopardus geoffroyi e L. colocolo s?o fel?deos neotropicais de pequeno porte, t?picos de ambientes abertos, que possuem distribui??o simp?trica na ecorregi?o da Savana Uruguaia. Nesta regi?o, L. geoffroyi ? considerada uma esp?cie abundante e L. colocolo um fel?deo raro. O presente estudo teve por objetivo avaliar essas proposi??es e caracterizar aspectos ecol?gicos das duas esp?cies nesta ecorregi?o amea?ada. O trabalho de campo foi conduzido entre novembro de 2013 e setembro de 2015, em propriedades rurais, na Serra do Caver?, sul do Brasil. Foram instaladas e monitoradas 26 armadilhas-fotogr?ficas e foram realizadas oito campanhas de captura visando ? coloca??o de radio-colares VHF, bem como a coleta de amostras de sangue dos indiv?duos de ambas as esp?cies. Como resultados, foram realizados 516 registros fotogr?ficos de L. geoffroyi e foram capturados 12 indiv?duos desta esp?cie, sete dos quais puderam ser monitorados com radio-telemetria. N?o foram encontrados registros de L. colocolo, indicando a escassez de indiv?duos desta esp?cie na ?rea de estudo. Em rela??o aos dados de L. geoffroyi, observou-se que os machos possuem ?reas de vida, de uso e peso corporal maiores do que as f?meas. Os resultados indicaram que o peso corporal dos machos influenciou positiva e significativamente no tamanho das ?reas de vida dos mesmos, rela??o esta que n?o ocorreu entre as f?meas. Tamb?m foi observada uma extensa sobreposi??o de ?reas de vida e de uso, sem grandes mudan?as sazonais, indicando algum grau de sociabilidade nesta popula??o. Os resultados da an?lise de parentesco indicaram que a maioria dos indiv?duos capturados desta popula??o n?o eram parentes. Ao mesmo tempo, a rela??o gen?tica parece n?o influenciar a sobreposi??o de ?rea de vida, o que sugere que esta popula??o, na escala estudada, possui uma estrutura s?cio-espacial aparentemente distante da proposi??o tradicional na qual os machos tenderiam a dispersar por maiores dist?ncias e as f?meas seriam filop?tricas. Al?m dos padr?es s?cio-espaciais, este estudo investigou fatores que influenciam na persist?ncia desta esp?cie na Savana Uruguaia. Foi poss?vel observar que esta popula??o selecionou significativamente mais as ?reas de vegeta??o rip?ria e evitou as ?reas de campos com gado. Cabe ressaltar que a prote??o da vegeta??o rip?ria ? exigida pela legisla??o nacional brasileira. Assim, este habitat pode fornecer abrigo para L. geoffroyi e hipoteticamente poderia servir como corredor ecol?gico, uma quest?o importante que precisa ser aprofundada no futuro. Esta popula??o tamb?m apresentou padr?es noturnos significativos que, consequentemente, evitam o contato humano. A estimativa de densidade foi considerada razo?vel em compara??o com a observada em outras ?reas, concordando com a proposi??o inicial para a esp?cie na regi?o. Os resultados desses estudos auxiliaram na compreens?o das caracter?sticas ecol?gicas da esp?cie e dos fatores que auxiliam sua persist?ncia nesta regi?o de paisagens dominadas por humanos. Tais esclarecimentos n?o foram poss?veis para L. colocolo, que n?o foi encontrado na ?rea de estudo. A aparente aus?ncia nesta ?rea, bem como em outras ?reas dentro da ecorregi?o, sugerem preocupa??o em termos da conserva??o desta esp?cie, o que torna-se ainda mais relevante tendo em vista que esta popula??o ? considerada uma ?Unidade Evolutivamente Significante? (UES) distinta. Assim, o quarto cap?tulo da tese objetivou estimar a distribui??o espacial atual e o status de conserva??o da UES de L. colocolo presente na Savana Uruguaia. Foram coletados 107 registros da esp?cie e foram constru?dos dois modelos (incluindo ou n?o vari?veis antr?picas), cada deles sendo gerado com dois algoritmos (Maxent e Maxlike). Os modelos resultaram em distribui??es similares, indicando as ?reas de campo com altitudes entre o n?vel do mar e 400m como aquelas apresentando mais elevada adequabilidade ou maior probabilidade de ocorr?ncia (PO). Os modelos que apresentaram melhor desempenho foram os que inclu?am as vari?veis antr?picas. Esses modelos geraram distribui??es mais restritas das ?reas de maior adequabilidade e PO, apoiando a conclus?o que essa popula??o de L. colocolo ? afetada por perturba??es humanas. A estimativa do tamanho populacional presente nas ?reas de maior adequabilidade e PO resultaram, respectivamente, nas categorias ?Criticamente em Perigo? e ?Em Perigo? para esta UES. Destaca-se, portanto, a necessidade urgente de planos de conserva??o para esta unidade populacional de L. colocolo. O estudo, em sua totalidade, observou que esp?cies de fel?deos com caracter?sticas tradicionalmente similares respondem de forma diferente aos impactos antr?picos. Os resultados obtidos podem contribuir para o desenho de a??es de manejo e conserva??o a fim de assegurar a sobreviv?ncia, em longo prazo, das duas esp?cies nesta ecorregi?o amea?ada.

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