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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.
251

Distribuição e abundância de Amazona vinacea (Papagaio-de-peito-roxo) no oeste de Santa Catarina

Zulian, Viviane January 2017 (has links)
Esse trabalho oferece uma avaliação da abundância do papagaio-de-peito-roxo (Amazona vinacea) para 2016 e 2017, combinando contagens em dormitórios ao longo de toda a distribuição da espécie, em escala global, com amostragens replicadas em dormitórios na região oeste de Santa Catarina (WSC), em escala local, Brasil. As contagens em escala global resultaram em 3888 e 4066 indivíduos em 2016 e 2017, respectivamente. As estimativas para o WSC foram de 945 ± 50 e 1393 ± 40 para os mesmos dois anos. Não foi observada nenhuma evidência de crescimento populacional de 2016 para 2017, pois o acréscimo no número de indivíduos foi acompanhado por aumento do esforço amostral em ambas escalas. Quando extrapolamos a abundância no WSC para toda a área de distribuição da espécie, segundo a IUCN, e pressupondo densidade homogênea, obtivemos valores que estão acima da contagem na escala global, mas dentro da mesma ordem de magnitude. Nosso resultado oferece uma base sólida para afirmar que o tamanho populacional global de A. vinacea é de milhares de indivíduos, mas não dezenas de milhares. Realizamos um esforço sistemático para considerar as principais fontes de incerteza na estimativa de abundância da espécie. Cada contagem, tanto na escala local quanto na global, incluíram visitas em todos os dormitórios conhecidos dentro de um intervalo de 10 dias, evitando duplas contagens devido ao movimento dos papagaios entre dormitórios. No WSC, a abundância foi estimada usando um N-Mixture Model implementado em contexto Bayesiano. Apesar de nossa estimativa de tamanho populacional e de área de distribuição serem maiores do que as consideradas pela IUCN, sugerimos que A. vinacea permaneça na categoria “Em Perigo”, até que sejam realizados estudos sobre tendência populacional. / We offer an assessment of Vinaceous parrot (Amazona vinacea) abundance in 2016 and 2017, combining roost counts over the whole range of the species, with a replicated survey of roosts at the local scale, in western Santa Catarina state (WSC), Brazil. The whole range counts amounted to 3888 and 4066 individuals in 2016 and 2017, respectively. The WSC estimates were 945 ± 50 and of 1393 ± 40 individuals, for the same two years. We found no evidence of population growth from 2016 to 2017 because the increase in numbers is accompanied by an increase in observation effort both in WSC and at the whole-range scale. When extrapolating the WSC abundance estimate to the whole IUCN extant range of the species under the simplifying assumption of homogenous population density, we obtain values above the whole-range counts, but within the same order of magnitude. Such result offers a sound basis for putting the global population size of A. vinacea in the thousands of individuals, but not in the tens of thousands of individuals. We made a systematic effort to address key sources of uncertainty in parrot abundance estimation. Each count, at the local or whole-range scale, includes visits to all relevant roosts within less than ten days time to avoid double counting due to movement between roosts. At the local scale, we estimated abundance using an N-Mixture Model of replicated count data, implemented in a Bayesian framework. Even though we estimate a larger population size and a bigger geographic range that those currently reported by the IUCN, we suggest that A. vinacea should remain in the ‘Endangered’ IUCN threat category, pending further investigation of population trends.
252

Amsonia kearneyana (Apocynaceae) Kearney’s Blue Star: New Insights to Inform Recovery

January 2015 (has links)
abstract: Amsonia kearneyana is an endangered herbaceous plant endemic to a small area of the Baboquivari Mountains in southern Arizona. It exists in two distinct habitat types: 1) along the banks of a lower elevation ephemeral stream in a xeroriparian community, and 2) a higher elevation Madrean oak woodland on steep mountain slopes. Half of the largest known montane population (Upper Brown Canyon) was burned in a large fire in 2009 raising questions of the species capacity to recover after fire. This research sought to understand how the effects of fire will impact A. kearneyana's ability to recruit and survive in the burned versus unburned areas and in the montane versus xeroriparian habitat. I compared population size, abiotic habitat characteristics, leaf traits, plant size, and reproductive output for plants in each habitat area for three years. Plants in the more shaded unburned montane area, the most populated population, presented with the most clonal establishment but produced the least amount of seeds per plant. The unshaded burned area produced more seeds per plant than in the unburned area. Lower Brown Canyon, the xeroriparian area, had the fewest plants, but produced the most seeds per plant while experiencing higher soil temperature, soil moisture, photosynthetically active radiation, and canopy cover than the montane plants. This could indicate conditions in Lower Brown Canyon are more favorable for seed production. Despite ample seed production, recruitment is rare in wild plants. This study establishes germination requirements testing soil type, seed burial depth, temperature regimes, and shade treatments. Trials indicate that A. kearneyana can germinate and grow in varied light levels, and that soil type and seed burial depth are better predictors of growth than the degree of shade. Finally, this study examined the law, regulation, policy, and physiological risks and benefits of a new management strategy and suggests that "conservation by dissemination" is appropriate for A. kearneyana. Conservation by dissemination is the idea that a protected plant species can be conserved by allowing and promoting the propagation and sale of plants in the commercial market with contingent collection of data on the fate of the sold individuals. / Dissertation/Thesis / Masters Thesis Plant Biology 2015
253

Distribuição e abundância de Amazona vinacea (Papagaio-de-peito-roxo) no oeste de Santa Catarina

Zulian, Viviane January 2017 (has links)
Esse trabalho oferece uma avaliação da abundância do papagaio-de-peito-roxo (Amazona vinacea) para 2016 e 2017, combinando contagens em dormitórios ao longo de toda a distribuição da espécie, em escala global, com amostragens replicadas em dormitórios na região oeste de Santa Catarina (WSC), em escala local, Brasil. As contagens em escala global resultaram em 3888 e 4066 indivíduos em 2016 e 2017, respectivamente. As estimativas para o WSC foram de 945 ± 50 e 1393 ± 40 para os mesmos dois anos. Não foi observada nenhuma evidência de crescimento populacional de 2016 para 2017, pois o acréscimo no número de indivíduos foi acompanhado por aumento do esforço amostral em ambas escalas. Quando extrapolamos a abundância no WSC para toda a área de distribuição da espécie, segundo a IUCN, e pressupondo densidade homogênea, obtivemos valores que estão acima da contagem na escala global, mas dentro da mesma ordem de magnitude. Nosso resultado oferece uma base sólida para afirmar que o tamanho populacional global de A. vinacea é de milhares de indivíduos, mas não dezenas de milhares. Realizamos um esforço sistemático para considerar as principais fontes de incerteza na estimativa de abundância da espécie. Cada contagem, tanto na escala local quanto na global, incluíram visitas em todos os dormitórios conhecidos dentro de um intervalo de 10 dias, evitando duplas contagens devido ao movimento dos papagaios entre dormitórios. No WSC, a abundância foi estimada usando um N-Mixture Model implementado em contexto Bayesiano. Apesar de nossa estimativa de tamanho populacional e de área de distribuição serem maiores do que as consideradas pela IUCN, sugerimos que A. vinacea permaneça na categoria “Em Perigo”, até que sejam realizados estudos sobre tendência populacional. / We offer an assessment of Vinaceous parrot (Amazona vinacea) abundance in 2016 and 2017, combining roost counts over the whole range of the species, with a replicated survey of roosts at the local scale, in western Santa Catarina state (WSC), Brazil. The whole range counts amounted to 3888 and 4066 individuals in 2016 and 2017, respectively. The WSC estimates were 945 ± 50 and of 1393 ± 40 individuals, for the same two years. We found no evidence of population growth from 2016 to 2017 because the increase in numbers is accompanied by an increase in observation effort both in WSC and at the whole-range scale. When extrapolating the WSC abundance estimate to the whole IUCN extant range of the species under the simplifying assumption of homogenous population density, we obtain values above the whole-range counts, but within the same order of magnitude. Such result offers a sound basis for putting the global population size of A. vinacea in the thousands of individuals, but not in the tens of thousands of individuals. We made a systematic effort to address key sources of uncertainty in parrot abundance estimation. Each count, at the local or whole-range scale, includes visits to all relevant roosts within less than ten days time to avoid double counting due to movement between roosts. At the local scale, we estimated abundance using an N-Mixture Model of replicated count data, implemented in a Bayesian framework. Even though we estimate a larger population size and a bigger geographic range that those currently reported by the IUCN, we suggest that A. vinacea should remain in the ‘Endangered’ IUCN threat category, pending further investigation of population trends.
254

Genética e conservação do guaiamum Cardisoma Guanhumi (Decapoda: Gecarcinidae) e dos seus habitats em Pernambuco

FALCÃO, Caio Bruno Ribeiro 23 February 2016 (has links)
Submitted by Natalia de Souza Gonçalves (natalia.goncalves@ufpe.br) on 2016-09-23T12:01:54Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Caio Bruno Ribeiro Falcão_Programa de Pós-Graduação em Genética_CB_2016.pdf: 1323776 bytes, checksum: 25bf87d5c7e7ecd8429e2f3db35e5bbc (MD5) / Made available in DSpace on 2016-09-23T12:01:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Caio Bruno Ribeiro Falcão_Programa de Pós-Graduação em Genética_CB_2016.pdf: 1323776 bytes, checksum: 25bf87d5c7e7ecd8429e2f3db35e5bbc (MD5) Previous issue date: 2016-02-23 / FACEPE / CNPQ / Os sistemas estuarinos da costa brasileira e sua fauna têm sido severamente impactados ao longo das últimas décadas. O Cardisoma guanhumi é um crustáceo difundido na culinária local do Nordeste do Brasil apresentando um grande valor de mercado, mas tem mostrado significativa diminuição nos seus estoques populacionais. A intensa captura de espécimes e a destruição de seus habitats incluiu C. guanhumi na Lista de Espécies da Fauna Ameaçadas de Extinção publicada em dezembro de 2014. Objetivando aferir a impactação sobre as populações de guaiamuns e sobre seus habitats ao longo de cinco estuários da costa pernambucana duas metodologias foram utilizadas: (i) análise de danificação genômica ao longo dos períodos de inverno e verão dos anos de 2012 e 2013, e (ii) avaliação de possíveis alterações da estrutura genética de C. guanhumi em um contexto espaço-temporal nos anos de 2012 e 2014. Os resultados das análises genotóxicas evidenciaram dano genômico no inverno do ano de 2012 que coincidiu com um rigoroso inverno e intensas chuvas atípicas para região. A avaliação da estruturação genética das populações nos dois anos não mostrou alterações significativas da diversidade genética nem mudança na estrutura da espécie. Os resultados obtidos sugerem que os manguezais/estuários pernambucanos têm recebido o aporte de componentes tóxicos, tendo em vista os danos genômicos detectados. Tais resultados alertam para a necessidade de uma maior atenção acerca da conservação dos manguezais/estuários pernambucanos. / Estuarine systems along the Brazilian coast and its wildlife have been severely impacted over the past decades. Cardisoma guanhumi is a crustacean widespread in local gastronomy of northeastern Brazil presenting a great market value, but has shown significant decrease in their population stocks. Intense capture of specimens and the destruction of their habitats included C. guanhumi in the Endangered Fauna Species List published in December 2014. In order to assess the impaction on the populations of blue crabs and about their habitats over five estuaries of the coast Pernambuco two methodologies were used: a genomic damage analysis over the winter and summer periods of the years 2012 and 2013 and an assessment of possible changes in the genetic structure of C. guanhumi in a space-time context in the years 2012 and 2014. The results of the analysis showed genomic genotoxic damage in the winter of 2012 year coincided with a harsh winter and heavy rains atypical for the region. The genetic structure of populations in both years showed no significant changes in the genetic diversity of the species or change in structure. The results suggest that mangroves / estuaries have received the injection of toxic components, considering the identified genomic damage. These results emphasize the need for greater attention on the conservation of Pernambuco estuaries.
255

Pequenos mamíferos da Mata Atlântica do Planalto Atlântico Paulista: uma avaliação da ameaça de extinção e da resposta a alterações no contexto e tamanho dos remanescentes / Small mammals of the Atlantic Forest of the Atlantic Plateau of São Paulo: an evaluation of the threat of extinction and the response to alterations in context and remnant size

Adriana de Arruda Bueno 19 September 2008 (has links)
Por meio de uma amostragem padrozinada de longa duração, realizamos levantamentos de pequenos mamíferos com armadilhas de interceptação e queda em 68 sítios distribuídos em seis paisagens de 10.000 ha (três em mata contínua e três em paisagens fragmentadas) localizadas em três regiões do Planalto Atlântico Paulista. As paisagens fragmentadas compreendem diferentes quantidades de matas remanescentes, 50%, 30% e 10%, porcentagens acima e próximas dos limites superior e inferior do limiar teórico de fragmentação (10-30%). A presente tese de doutoramento foi dividida em quatro capítulos e duas abordagens principais. A primeira delas (Capítulo 2) teve por objetivo avaliar se os pequenos mamíferos listados como ameaçados de extinção são afetados pela fragmentação e pela qualidade dos remanescentes de Mata Atlântica do Planalto Atlântico Paulista. Para isso, utilizamos os dados coletados nos 68 sítios amostrados, os quais estavam distribuídos em oito categorias: nove em matas maduras contínuas, nove em matas secundárias contínuas, quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 50% de remanescentes, sete em fragmentos grandes e 13 em fragmentos pequenos da paisagem com 30% de remanescentes, e quatro em fragmentos grandes e 11 em fragmentos pequenos da paisagem com 10% de remanescentes. Avaliamos se 10 espécies de pequenos mamíferos listados como ameaçados de extinção e cinco espécies endêmicas comuns nas mata contínuas e ausentes das listas vermelhas são afetados igualmente pela fragmentação, na escala da paisagem e da mancha, e pela qualidade dos remanescentes de Mata Atlântica. Nenhuma das espécies analisadas, independentemente do grau de ameaça ou de raridade, respondeu a variação do estádio de regeneração das matas contínuas. Por outro lado, nossos dados mostraram que as espécies endêmicas comuns respondem de forma mais congruente e negativamente à perda e fragmentação da Mata Atlântica do que as ameaçadas, as quais tanto podem não ser afetadas quanto ser positivamente ou negativamente afetadas pela fragmentação. Assim, sugerimos a separação das espécies em dois grupos nas listas vermelhas (naturalmente raras versus afetadas pelas ações antrópicas) e a utilização de outros critérios para avaliar o status de ameaça das espécies mais comuns, como a resposta à perda e fragmentação do habitat e a especificidade ao habitat na forma de endemismos e de grau de tolerância a matriz. A segunda abordagem (Capítulo 3) teve como objetivo verificar a influência do contexto (paisagem) e do tamanho do fragmento em paisagens com quantidades diferentes de remanescentes sobre a riqueza e abundância de espécies endêmicas e não-endêmicas. Para isso, utilizamos dados de 50 dos 68 fragmentos amostrados, localizados nas três paisagens 114 fragmentadas com 50%, 30% e 10% de remanescentes. A partir da avaliação da plausibilidade de oito modelos de regressão, que expressam visões teóricas alternativas da importância do contexto e da área dos fragmentos, investigamos se a influência positiva da área das manchas de floresta é mais forte (1) para as espécies endêmicas e (2) na paisagem próxima ao limite superior do limiar de fragmentação (sensu Andrén, 1994), já que em contexto de muita mata remanescente, fragmentos pequenos e grandes poderiam abrigar populações viáveis, e em contexto de pouca mata remanescente, espécies sensíveis já teriam desaparecido. Com exceção da riqueza de espécies não-endêmicas, modelos que incluem o contexto foram as hipóteses mais plausíveis para descrever a variação da riqueza e abundância das espécies de pequenos mamíferos. Como esperado, a influência positiva da área do fragmento foi mais importante na paisagem com 30% de floresta para a maioria das espécies de pequenos mamíferos endêmicos, enquanto que os modelos que incluem a influência da área do fragmento não estiveram entre os mais plausíveis para as espécies não-endêmicas. Nossos resultados corroboram a existência de um limiar de fragmentação e indicam que, ainda que os limiares variem entre espécies, é possível identificar grupos com respostas semelhantes à perda e fragmentação do habitat, auxiliando as políticas de manejo e conservação. / A long-term standardized survey of the Atlantic Forest small mammals was conducted using pitfall traps in 68 sites distributed in six 10.000-ha landscapes (three in continuous forest and three in fragmented landscapes) located in three regions in the Atlantic Plateau of São Paulo. The fragmented landscapes harbored different amounts of remnants, 50%, 30% and 10%, percentages above or within the superior and inferior limits of the theoretical fragmentation threshold (10-30%). This thesis was divided in four chapters e two main approaches. The first approach (Chapter 2) aimed to evaluate if small mammals listed as threatened were affected by forest fragmentation and quality in the Atlantic Plateau of São Paulo state. For this, we used data from 68 sites distributed in eight categories: nine in mature continuous forests, nine in secondary continuous forests, four in large and 11 in small patches in the landscape with 50% of remnants, seven in large and 13 in small patches in the landscape with 30% of remnants and four in large and 11 in small patches in the landscape with 10% of remnants. We investigated if 10 threatened small mammals and five non-threatened endemic species commonly found in continuous forests were equally affected by fragmentation, at the landscape and patch scales, and by forest quality. Regardless of threat or rarity level, no analyzed species responded to differences in the regeneration stage in continuous forests. On the other hand, our data showed that common endemic species respond more strongly and negatively to the loss and fragmentation of the Atlantic Forest than threatened species, which either may not be affected by fragmentation, or be positively or negatively affected. we suggest separating species in two groups (naturally rare versus affected by human impact) in the Red Lists and including different criteria to evaluate common species such as response to habitat loss and fragmentation as well as habitat specificity in terms of endemism and level of matrix tolerance. The second approach (Chapter 3) aimed to evaluate the effects of context (landscape) and patch area in landscapes with different amounts of remnants on the richness and abundance of the endemic and non-endemic species. We used data from 50 sites located in the three fragmented landscapes. By analyzing the plausibility of eight regression models, which express alternative theoretical hypothesis about the importance of context and patch area, we investigate if the positive influence of patch area was stronger (1) for endemic species and (2) in the landscape within the superior limit of the fragmentation threshold (sensu Andrén, 1994), since in a context of high proportion of remnants, small and large patches could harbor viable populations and in a context of low proportion of remnants, sensitive species would have gone extinct. Except for the non116 endemic species richness, the models including context were the most plausible hypothesis to describe small mammal richness and abundance variations. As expected, the positive influence of patch area was more important in the landscape with 30% of remnants for the majority of the endemic small mammals, whereas the models including patch area were not among the most plausible ones for the non-endemic species. Our data corroborate the existence of a fragmentation threshold and point out that, although thresholds vary among species, it is possible to identify groups with similar response to habitat loss and fragmentation, directing management and conservation policies.
256

Macroecological patterns of plant species and anthropogenic activities

Correa Cano, María Eugenia January 2015 (has links)
The study of macroecology not only identifies patterns in the distribution and abundance of species at large spatial and temporal scales, it also gives insight into the processes underlying those patterns. The contribution of this work is not limited to helping develop the field of ecology per se, but also provides important insights into the understanding of large scale processes like climate change, the spread of introduced species, pest control and how increasing pressure from anthropogenic activities threatens biodiversity and ecosystem services. During the first decade following its formal inception, most of the progress in macroecology was made through studies of animal species, and research into plant species continues to lag far behind. This thesis contributes to the study of the macroecology of plant species by examining some selected macroecological patterns that have been studied only for animal species and by including an important issue that might have significant effects on diverse macroecological patterns, namely anthropogenic activities. The second and third chapters of the thesis address the generalised individuals-area relationship (GIAR) and the patch individuals-area relationship (PIAR), two macroecological relationships not previously explored for plant species. I show for the first time the existence of negative GIARs at the intraspecific and interspecific levels in plant species, similar to those documented for animal species. Unlike animal species, I did not find a broadly consistent intraspecific PIAR in plant species; more than half of the tested species showed negative PIARs. The resource concentration hypothesis may help explain those positive PIARs that were observed. The fourth chapter considers the effect of past human activities on current patterns of plant species richness at a landscape scale. Using a detailed database on the historical anthropogenic activities for Cornwall, U.K., I examine the relationship between species richness and the area covered by each historical land-use at two different spatial resolutions (10km x 10km and 2km x 2km). I find that at the 10km x10km scale human activities carried out since the 17th and 19th centuries explain an important proportion of the variation in current plant species richness. In contrast, a model at 2km x 2km scale with upland woods and the total land area of a grid cell explain only 5% of the variation. The fifth and sixth chapters focus on how artificial light at night (ALAN), which has increasingly come to attention as a significant anthropogenic pressure on species, is interacting with the distributions of plant species. In the fourth chapter, I consider the plant family Cactaceae to determine the proportion of the global distribution ranges of species that is being influenced by ALAN, and how this changes with the size of these distribution ranges and over a 21-year period (1992 to 2012). I found that >80% of cacti species are experiencing ALAN somewhere in their distribution range, and that there is a significant upward trend in ALAN in the ranges of the vast majority of species. For the sixth chapter, I consider similar issues for the threatened plant species of Britain, exploiting new remote sensing imagery of nighttime lighting at a very fine spatial resolution (c.340x340m2). Only 8% of Britain is free of artificial light at night and in consequence a high number of threatened plant species have a high proportion of their range under some influence of ALAN.
257

Influence of anthropogenic stressors on the behaviour and mortality of the endangered African penguin

Nyengera, Reason January 2014 (has links)
This study investigated the potential impacts of several anthropogenic stressors on the movement and survival of African penguins in Algoa Bay, taking into account prey availability and environmental conditions (sea surface temperature and chlorophyll productivity). The primary drive for the study was based on the seismic exploration, which took place in the habitat of the endangered African penguin. The research was also carried out to understand how pelagic fishing and prey availability influence the broader behavioural and mortality aspects of penguins. To achieve this goal, I used monthly beach surveys to assess seabird mortality, admissions of penguins in rehabilitation centres and the monitoring of breeding penguins’ movement at sea through individual GPS tracking. In addition, prey distribution and abundance were monitored with acoustic surveys to assess potential changes in relation anthropogenic stressors. Breeding African penguins did not react dramatically to seismic activities, except on St Croix Island where they changed their foraging direction during the seismic period. There was no evidence of a siginficant increase in African penguin carcasses encountered or strandings along the beaches during the period of seismic activity. However, a sharp increase in encounter rate was recorded soon after seismic operations, which may potentially indicate a delay between the effect of seismic activities on penguin mortality and the encounter of the related carcasses after the operation. However, the impact of seismic surveys on penguins may be long-term rather than short term, and additional studies would be needed to reveal long-term effects of seismic activities, if any. Foraging effort of breeding African penguins increased substantially in the presence of commercial fishing activities within close proximity to the colonies. To a greater extent, at-sea movement patterns and counts of beach cast carcasses were largely influenced by prey availability. Penguins spent more time at sea, traveled longer and covered a larger foraging area during periods of relatvely low pelagic fish abundance. There was also a sharp increase in African penguin mortality during periods of low prey availability in the Bay. However, environmental conditions showed some influence over these interactions. Foraging effort of breeding African penguins increased substantially in the presence of commercial fishing activities within close proximity to the colonies. To a greater extent, at-sea movement patterns and counts of beach cast carcasses were largely influenced by prey availability. Penguins spent more time at sea, traveled longer and covered a larger foraging area during periods of relatvely low pelagic fish abundance. There was also a sharp increase in African penguin mortality during periods of low prey availability in the Bay. However, environmental conditions showed some influence over these interactions. For example a red tide event during in period of low prey availability, made it difficult to understand impacts of prey on penguins difficult. Both anthropogenic stressors and environmental conditions influenced African penguins’ behaviour and survival. Due to the worrying trend of African penguins in South Africa for the past few years, all conservation management efforts to increase penguin numbers and limit their mortality are necessary. This study highlights the negative impact of industrial fishing on this Endangered species and the rapid increase in mortality of penguins during times of low prey availability. A network of Marine Protected Areas would certainly increase food availability to African penguins by limiting competition with fisheries, and contribute to increasing the population numbers.
258

Mezinárodní obchod s ohroženými druhy zvířat(včetně derivátů) / International Trade in Endangered Wildlife (including derivatives)

Bartůňková, Lenka January 2012 (has links)
In the course of the 20th century the un-sustainability of international wildlife trade became apparent. European countries play a major role in wildlife trade. One third of total wildlife imports is destined to the EU which makes EU responsible for the protection of world wildlife and should motivate the EU to be a model in biodiversity protection. Regulation of wildlife trade in the EU is discussed in chapter 1. Trade in wildlife and its derivatives is among the most profitable branches of the international trade. Animals are traded in different forms. Birds are usually traded live (for the pet trade), mammals are traded for their fur, butterflies for their bodies, reptiles for their skins, the highest value is attained by trade in fish. In some categories (live birds, caviar) EU imports more than the rest of the world combined. The EU plays a major role as an importer in other categories as well. The magnitude, value and trends of international wildlife trade are discussed in chapter 2. Profitability of the wildlife trade, strong demand for some products and imperfect implementation of CITES result in the development of illegal trade. Illegal wildlife trade is dominated by organized criminal groups that also deal in drugs and human trafficking. Illegal wildlife trade is linked to severe risks and dangers to both the source country and the recipient. More on illegal wildlife trade in chapter 3. EU imports one third of all legally exported wildlife products. It is also the importer of a majority of illegal wildlife products. Having one of the highest standards of living and seeing that the care of environment cannot be limited by political borders, the author of this thesis concludes that it is logical and imperative that the EU engages in improvement of wildlife protection in less developed countries of the world. The last chapter deals with conservation of Cameroonian Dja Biosphere Reserve and with the attempt of large EU's environmental programs to improve conservation in Cameroon.
259

An analysis of enforcement of laws on rhino poaching in South Africa

Mogoshi, Malesela Samuel January 2016 (has links)
Thesis (LLM.) -- University of Limpopo, 2016 / Rhinoceros (Rhinos) are poached at an alarming high rate in South Africa. The 1973 Convention on International Trade in Endangered Species of wild Fauna and Flora (CITES), prohibited the trade of rhino horns amongst its member states. Even though there are existing pieces of legislation in South Africa to curb the killing and illegal trade of rhino horns, compliance authorities rarely impose stringent sentences on culprits caught poaching rhinos. There should be stringent enforcement of laws on poachers and if caught, perpetrators should be brought to justice in order to deter aspiring or ambitious would-be perpetrators. Amendment of legislation currently used in South Africa on rhino poaching cases, if applied vigorously, would be more developmental in curbing the scourge. The syndicate are highly skilled and well equipped for the execution of illicit poaching. It is in few instances that perpetrators are arrested and prosecuted. Even if arrested and prosecuted, lenient sentences are imposed upon conviction. The most noticeable lacuna in South African Criminal Justice System, is the lack of capacity and skills in investigations and successful prosecutions of rhino poachers. Worst still, despite frequent media reports on the alarming rate of rhino poaching cases, few arrests and convictions are reported. This mini dissertation looks at rhino poaching as an organised crime, and focuses on literature review, legal framework and regulations, as well as comparative study on legislation which can be used to prosecute the perpetrators of this organised crime. The discourse recommends amendment of legislation presently used to prosecute rhino poaching offenders, and advocates that they should be stringently applied in order to curb the scourge.
260

Using Network Models to Predict Steelhead Abundance, Middle Fork John Day, OR

Blanchard, Monica R. 01 May 2015 (has links)
In the management of threatened and endangered species, informed population estimates are essential to gage whether or not recovery goals are being met. In the case of Pacific salmonids, this evaluation often involves sampling a small subset of the population and scaling up to estimate larger distinct populations segments. This is made complicated by the fact that fish populations are not evenly distributed along riverscapes but respond to physical and biological stream properties at varying spatial extents. We used rapid assessment survey methods and the River Styles classification to explore fish-habitat relationships at a continuous network scale. Semi-continuous surveys were conducted across nine streams in the upper Middle Fork John Day River watershed and increased the number of sites surveyed eight-fold over other monitoring methods within the watershed. Using this increased sample size and continuous habitat metrics we improved watershed-wide steelhead (Oncorhynchus mykiss) abundance models. We first validated the distinctions among River Styles through a classification analysis using physical metrics measured at the rapid assessment sites. Overall classification accuracy, using a combination of reach and landscape scale metrics, was 88.3% and suggested that River Style classification was identifying variations in physical morphology within the watershed that was quantifiable at the reach scale. Leveraging the continuous River Styles classification of physical habitat and a continuous model of primary production improved the prediction of steelhead abundance across the network. Using random forest regressions, a model that included only habitat metrics resulted in R2 = 0.34, while using the continuous variables improved the model accuracy greatly to R2 = 0.65. Random forest allowed for further investigation into the predictor variables through the analysis of the partial dependence plots and identified a gross primary production threshold, below which production might be limiting steelhead populations. This method also identified the rarest River Style surveyed within the watershed, Confined-Valley Step Cascade, as the morphology that had the largest marginal effect on steelhead. The inherent physical properties and boundary conditions unique to each River Style has the potential to inform fish-habitat relationships across riverscapes and improve abundance estimates on a continuous spatial scale.

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