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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.
141

Ecologia Populacional de Bugios-Ruivos (Alouatta guariba) nos Municípios de Porto Alegre e Viamão, RS, Brasil. / Population ecology of free-ranging brown howler monkeys (Alouatta guariba clamitans) in southern Brazil

Jardim, Marcia Maria de Assis 04 August 2018 (has links)
Orientador: Eleonore Zulnara Freire Setz / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-04T03:03:59Z (GMT). No. of bitstreams: 1 Jardim_MarciaMariadeAssis_D.pdf: 906770 bytes, checksum: 81b5c547024efb307fcafd7bdc02a344 (MD5) Previous issue date: 2005 / Resumo: Parâmetros populacionais são importantes indicadores de como as populações estão superando condições desfavoráveis e quais as suas perspectivas de sobrevivência a longo prazo. No período de dezembro de 1999 a dezembro de 2001, nós acompanhamos bimestralmente 10 grupos de bugios ruivos (Alouatta guariba clamitans) residentes em três fragmentos florestais nos municípios de Porto Alegre e Viamão, RS. Foram realizadas 13 expedições nas quais foram registrados os seguintes dados: data, horário, local e composição social de cada grupo. O intervalo médio entre os monitoramentos foi de 50,2 dias, totalizando 149 dias de campo e 219 encontros com grupos de bugios. O tamanho médio dos grupos foi de 8,2 indivíduos, sendo 1,3 machos adultos; 2,6 fêmeas adultas; 0,3 machos subadultos; 0,8 juvenis II; 2,3 juvenis I; 0,6 infantes II e 0,4 infantes I. Todos os grupos apresentaram alterações na composição social ao longo dos dois anos. Foram registrados 31 nascimentos, sendo a taxa anual de natalidade de 0,6 por fêmea adulta. O intervalo médio entre os nascimentos foi estimado em 14,7 meses. No decorrer do período, foram observados 16 casos de desaparecimentos (emigrações e/ou mortes) e uma imigração de uma fêmea adulta. Para enriquecimento da análise foram considerados mais cinco casos de desaparecimentos ocorridos em 1999 nos grupos de estudo, observados no período piloto e através de relatos de outros pesquisadores. Ao longo dos dois anos de monitoramento, o tamanho médio de área de vida estimado para os dez grupos foi de 4,4 ha pelo método do polígono mínimo convexo e 4,2 ha pelo método de esquadrinhamento (25x25m). A área de uso individual variou entre 0,2 a 1,1; com média de 0,5 ha por indivíduo. A sobreposição de áreas de uso variou de 0 a 39%. A densidade populacional e o tamanho de fragmentos foram os fatores mais determinantes no tamanho da área de uso e parecem ser melhores previsores para a espécie como um todo. Os resultados demonstraram um tamanho de grupo médio superior ao encontrado na literatura, altas taxas reprodutivas e variações relevantes na composição social dos grupos, indicando uma situação de crescimento populacional e dinâmica dos grupos intensa. A sobrevivência destas populações a longo prazo, no entanto, é incerta, devido à alta pressão de ocupação urbana e conseqüente fragmentação do hábitat, dificultando a dispersão efetiva dos indivíduos e aumentando as chances de depressão por endocruzamento / Abstract: Population parameters are important indicators of how populations are overcoming unfavourable conditions and of their perspectives of long term survival. Ten groups of brown howler monkeys (Alouatta guariba clamitans) living in three forest fragments around the cities of Porto Alegre and Viamão, RS, were followed bimonthly from December 1999 to December 2001. Thirteen expeditions were carried out and the following information was registered: date, time, location, and social composition of each group. The average interval between the expeditions was 50.2 days, with a total of 142 days on site and 214 encounters with groups of howler monkeys. The groups had an average size of 8.2 individuals, 1.3 adult males; 2.6 adult females; 0.3 subadult males; 0.8 juveniles II; 2.3 juveniles I; 0.6 infants II and 0.4 infants I. All groups presented alterations in social composition during the two-year period. Thirty-one births were registered, with an annual birth rate of 0.6 per adult female. The average interval between births was estimated in 14.7 months. Sixteen disappearances cases (emigrations and/or deaths) and the immigration of one adult female were observed during this period. Five additional disappearances cases within the study groups were considered in order to enhance the analysis. They all occurred in 1999 and were observed during the pilot period or reported by other researchers. The estimated average home range of all ten groups during the two-year monitoring was 4.4 ha using the minimum convex polygon method, and 4.2 ha using the grid method (25x25m). The area of individual use varied between 0.2 and 1.1, with an average of 0.5 ha per individual. The overlap of home range varied between 0 and 39%. Population density and size of fragments were the most important factors determining the size of use area and seem to be better predictors for the species as a whole. The results demonstrated an average group size superior to that found in literature, high reproductive rates and relevant variations in the social composition of groups, indicating population increase and intense group dynamics. However, the long term survival of these populations is uncertain due to the high pressure of urban occupation and the consequent fragmentation of their habitat, making the effective dispersal of individuals more difficult, and increasing the chances of depression by inbreeding / Doutorado / Ecologia / Doutor em Ecologia
142

Dinâmica espacial, migração e preferência de micro-hábitat de Aegla longirostri bond-buckup e buckup, 1994 (crustacea, anomura, aeglidae) / Spatial dynamic, migration and microhabitat preference of Aegla longirostri bond-buckup e buckup, 1994 (crustacea, anomura, aeglidae)

Baumart, Joele Schmitt 25 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Understanding the population dynamic processes is fundamental to access its viability (health). Great part of these processes is closely related to the organism densities in a studied population. These data can reveal how the population is arranged in the environment and, in adverse conditions, it is possible to forecast the occurrence of dispersion/migration. This study aims to investigate some ecological parameters of an Aegla longirostri population, a freshwater anomuran from the southern Brazil: (i) to estimate the population density, (ii) the substrate preference, (iii) the home range and (iv) the possible dispersion patterns. The study site was the first order stream Sanga do Caranguejo, located in the central region of Rio Grande do Sul State, during 2010 and 2011. For population density and dispersion investigation covo traps were used, distributed through the stream, in different times in the year. The study of the substrate preference used PVC gutters covered by mesh and arranged on the stream substrate, with controlled density population; a surber was used for active search in the stream. The home range analysis used radio telemetry techniques. The population size was estimated in 950 individuals in spring and 210 in autumn (estimated according to the Bayesian Method). With respect to the substrate preference, we found that there is an ontogenetic association regarding the choice. The juveniles, in the first development stages, prefer sandy substrates, while adults (males and females) prefer more complex substrates. The estimates of home range of eglids vary between 8,41 to approximately 45,49 linear meters of stream, and these crustaceans showed the local dislocation, once they perform their activities around a specific point in the stream. To finalize, we identified that the juveniles and adults of eglids are active walkers, not being carried by the flow in a passive way as occurs in larvae stage in other crustaceans. Its activities are related to the environment temperature and density of adult males. We believe that the knowledge about the group has increased, however, as it is a complex group, with a rich evolutionary history, much remain to be investigated about these freshwater crustaceans. / A compreensão dos processos de dinâmica populacional é fundamental para se avaliar a viabilidade (saúde) de uma população. Grande parte desses processos estão estreitamente relacionados com a densidade de organismos da população estudada. Estes dados podem revelar como a população está distribuída no ambiente e, em condições de adversidade ambiental, é possível prever a ocorrência de dispersão/migração. Neste estudo, alicerçado nos fatores ecológicos e biológicos do aeglídeo Aegla longirostri foram investigados: (i) estimativa da densidade populacional, (ii) as preferências de substrato, (iii) a área de vida e (iv) os possíveis padrões de dispersão. Este estudo foi conduzido em um riacho de primeira ordem, Sanga dos Caranguejos, que se localiza na região central do Rio Grande do Sul, durante os anos de 2010 e 2011. Nas investigações sobre densidade populacional e dispersão foram utilizados coletores do tipo covo espaçados pelo riacho, em diferentes estações climáticas do ano. A investigação de preferência de substrato foi conduzida com o uso de calhas de PVC cobertas por malha e dispostas no riacho para o experimento em condições de densidade controlada, e com surber, para busca ativa no riacho. A análise de área de vida foi realizada com a utilização da técnica de rádio telemetria. A população em questão foi estimada em 950 indivíduos na primavera e 210 indivíduos no outono (estimativas segundo o Método Bayesiano). Com relação à preferência de substrato, verificamos que há associação ontogenética quanto à escolha. Os juvenis, nos primeiros estágios de desenvolvimento, preferem substratos arenosos, enquanto que adultos (machos e fêmeas) preferem substratos mais complexos. Estimou-se também que a área de vida desses eglídeos varia desde 8,41 metros até, aproximadamente, 45,49 metros lineares de riacho, e que estes crustáceos apresentam comportamento de deslocamento local, já que realizam suas atividades em torno de um ponto específico do riacho. Observou-se ainda que os juvenis eglídeos, assim como os adultos, são caminhadores ativos, não sendo carregados pela correnteza de forma passiva como ocorre nas fases larvais de outros crustáceos. Suas atividades estão relacionadas com a temperatura do ambiente e com a densidade de adultos machos no riacho. Acreditamos que muito se avançou em termos de conhecimento da ecologia do grupo como um todo, e não apenas para a espécie estudada, servindo este estudo de base para estudo futuros sobre dispersão e área de vida principalmente.
143

HISTÓRIA NATURAL DE Tupinambis merianae (SQUAMATA, TEIIDAE) NA ESTAÇÃO ECOLÓGICA DO TAIM, EXTREMO SUL DO BRASIL / NATURAL HISTORY OF Tupinambis merianae (SQUAMATA, TEIIDAE) IN TAIM ECOLOGICAL STATION, SOUTHERN BRAZIL

Winck, Gisele Regina 13 February 2007 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The genera Tupinambis comprises the largest lizards of America, which could reach 500 mm of corporal length. Two species possess wide distribution in South America (T. teguixin and T. merianae), while the others are restricted the specific biome (Amazonian Forest, Savannah and Chaco). The species T. merianae have the widest distribution of the gender, from the south of the Amazonian Forest to the north of Patagonia, at the east of Andes. In the present study, 640 h of sampling were accomplished (320 h of observations in the area to analyses of behavior; 320 h of observation along transects), in the total of 64 days. In the summer, there were no registrations of active lizards before 7:37 in the morning, nor after 17:43 of the afternoon. The use of community hibernacula was registered for the winter dormancy, being the burrows dug in cemented constructions used more frequently in the observation area. As for the seasonal activity, the first individuals emerged in August and the last ones returned to the dormancy in April. The emergency of the population demonstrated to be protandric, with adults emerging before juvenile. In the period after emergency, the males were basking in aggregations of up to 13 individuals, which changed of positions through audible resonant signs. Besides, sibilated sounds can be emitted in stress situations or agonistic interactions. There was significant difference of activity among the different certain periods in this study, along the months (F = 16.6; p <0.01), being October and December the months with registration of the individuals' larger activity. There was fluctuation in the population size and in the activity of the different age classes along the months. The minimum home range for three males and two females (variation from 0.05 to 20.29) were registered. The area of use of the animals did not differ along the months, but it was possible to observe gregarious behavior during the nine months of study. / No gênero Tupinambis estão representados os maiores sáurios das Américas, podendo atingir 500 mm de comprimento corporal. Duas espécies possuem ampla distribuição na América do Sul (T. teguixin e T. merianae), enquanto as demais são restritas a biomas específicos (Floresta Amazônica, Cerrado e Chaco). A espécie T. merianae possui a distribuição mais ampla do gênero, ocorrendo do sul da Amazônia ao norte da Patagônia, ao leste dos Andes. No presente estudo foram realizadas 640 h de amostragem (320 h de observações na área de análises de atos comportamentais; 320 h de observação ao longo de transectos), no total de 64 dias. No verão, não houve registros de lagartos ativos antes das 7:37 da manhã, nem após 17:43 da tarde. Foi registrada a utilização de hibernáculos comunitários para a dormência de inverno, sendo as tocas escavadas em artefatos de concreto, utilizadas com maior freqüência na área de observação. Quanto à atividade sazonal, os primeiros indivíduos emergiram em agosto e os últimos retornaram à dormência em abril. A emergência da população demonstrou ser protândrica, com adultos emergindo antes dos juvenis. No período pósemergência, os machos termorregularam em agregações de até 13 indivíduos, os quais trocavam de posições através de sinais sonoros audíveis. Além disso, sons sibilares podem ser emitidos em situações de stress ou interações agonísticas. Houve diferença significativa de atividade entre os diferentes períodos determinados neste estudo, ao longo dos meses (F = 16.6; p < 0.01), sendo outubro e dezembro os meses com registro de maior atividade dos indivíduos. Foi registrada flutuação no tamanho populacional e na atividade das diferentes classes etárias ao longo dos meses. A área mínima de vida para três machos e duas fêmeas (variação de 0.05 a 20.29) é apresentada. A área de utilização dos animais não diferiu ao longo dos meses e foi possível observar comportamento gregário durante os nove meses de estudo.
144

Identifier les contraintes pour la conservation des dernières girafes de l’Afrique de l’Ouest : déterminants de la dynamique de la population et patron d’occupation spatiale / Identifying conservation constraints for the last West African giraffe : population dynamics determining factors and spatial distribution pattern

Suraud, Jean-Patrick 16 December 2011 (has links)
Le défi de la protection des espèces menacées en Afrique est de concilier de façon durable les objectifs de conservation de la nature, et la nécessité de développement économique des populations humaines. Au Niger, survivent aujourd'hui les dernières girafes d'Afrique de l'Ouest (Giraffa camelopardalis peralta). Ces girafes sont unique à plusieurs titres : (i) elles constituent les seules représentantes de la sous espèce peralta (ii), elles vivent dans une région fortement anthropisée (iii) elles vivent dans une zone non protégée, (iv) et elles ne cohabitent avec aucun prédateur. En 1996, la population était au bord de l'extinction avec seulement 50 individus. Malgré des signes de restauration observés ces dernières années, la sous-espèce est inscrite depuis 2008 dans la liste rouge des espèces menacées de l'UICN (Union Internationale pour la Conservation de la Nature) avec le statut « en danger ». Quels sont les facteurs qui pourraient limiter le taux de croissance maximum récemment observé dans cette population? Est-ce que les conjonctures favorables à l'augmentation de la population sont durables? Aborder les questions de conservation des populations met en avant le besoin de connaitre les paramètres démographiques de la population concernée, et les paramètres environnementaux qui conditionnent sa distribution spatiale. Nous avons réalisé une analyse de l'historique des comptages, puis, nous avons déterminé les paramètres démographiques de la population grâce à une approche par Capture Marquage Recapture. Une analyse spatiale à plusieurs échelles nous a permis de caractériser la distribution des girafes aux niveaux de la population et du troupeau (à partir d'observations directes), et de mesurer la sélection de l'habitat au niveau individuel (à partir d'un suivi par colliers GPS) / One of the main challenges for endangered species protection in Africa is to find a sustainable way of integrating objectives of nature conservation with the economic development needs of the local human population. Last West African giraffe population, Giraffa camelopardalis peralta, lives in Niger. These giraffe are unique for several reasons: (i) they represent the only population of peralta sub-species, and (ii) they live in an area densely populated by humans, (iii) which is unprotected and (iv) without predators. In 1996, this giraffe population was almost extinct, with only 50 individuals remaining. Despite signs of population recovery, the sub-species has been classified as “endangered” according to the IUCN Red List assessment criteria. What are the limiting factors for the maximum annual growth rate that has been recorded over the last years in the population? Are favorable conjunctures to this population increasing sustainable? Assessing population conservation requires knowledge of demographic parameters and understanding of the environmental factors driving its spatial distribution. Census data from 1996 to 2009 were analyzed and then demographic parameters through a capture-markrecapture method were determined. A multi-scale spatial analysis allowed me to determine giraffe distribution at both population and herd level (through observations), and to measure habitat selection at the individual level (through GPS satellite collars). Census results, almost exhaustive from 2005 to 2008 highlited an annual growth rate of 12%. This is the maximum growth rate for a giraffe population, and fits with the theoretical maximum growth rate for the species. At the population and herd level, giraffe distribution patterns are driven by food availability. These food resources are seasonally distributed and impacted by human activities. Habitat selection shows that during dry season, giraffe avoid village proximity, where disturbance is high. However, at night giraffe move closer to villages where food resource quantity and quality are higher (tree density, granaries). The use of bean field crop suggests that some cultivated crops gain in attraction and even become favourable to giraffe. This might explain the increase of human-giraffe conflicts. My results clearly show the importance of taking human activities and perception into account, when assessing wildlife conservation strategies
145

Demography, Movement Patterns, and Habitat Selection of Blanding's Turtles at Canadian Nuclear Laboratories in Chalk River, Ontario

Hawkins, Emily January 2016 (has links)
The development and implementation of effective species and population-specific management strategies requires population-specific information. To demonstrate the relative extirpation risk associated with various road mortality scenarios for a population of Blanding’s turtles at Canadian Nuclear Laboratories in Chalk River, Ontario, a Population Viability Analysis was conducted. Road mortality of two adult females every ten years resulted in population extirpation within 200 years relative to a stable population not experiencing road mortality. To accommodate informed decision-making for the management of this species at risk, the movement patterns and habitat selection of this Blanding’s turtle population were described. There was no significant difference between males and females in distance moved between relocations in either the spring or the summer, but turtles moved greater distances in the spring than in the summer. Annual and seasonal home range size did not differ between the sexes or between spring and summer periods. A compositional analysis indicated Blanding’s turtles preferred marsh habitats over bog, swamp, lake, and upland. Matched-paired logistic regression was used to determine selection of microhabitat features, such as type of vegetation, in the spring and summer. Turtles preferred sites with warmer air temperatures, shallower water, a higher availability of open water, and greater coverage of emergent and floating vegetation types in the spring period. In the summer period, turtles preferred sites characterized by cooler, deeper water, a higher availability of open water, and greater coverage of emergent and floating vegetation types. This population of Blanding’s turtles appears to be relatively small and the continued threat of road mortality indicates a delicate situation for its persistence. Considering seasonally preferred habitats will best inform management decisions for seasonal work restrictions and future development plans.
146

Seasonal movements of black-tailed deer on northern Vancouver Island

Harestad, Alton Sidney January 1979 (has links)
Columbian black-tailed deer (Qdocoileus hemionug cplumbianus Richardson) were radio-tagged in a deep snowfall region on northern Vancouver Island, British Columbia. These deer were monitored to determine seasonal movements and habitat use. Deer exhibited either resident or migratory movement patterns. Resident deer made seasonal shifts in their home range centres but their seasonal home ranges overlapped. In migratory deer, summer home ranges were separated from both spring and winter home ranges, although their spring and winter home ranges overlapped. Altitudinal migrations occurred by deer moving between high and low elevation habitats. Horizontal migrations occurred by deer moving between a small tributary valley and the main valley. Seasonal movements of black-tailed deer result from habitat selection by deer seasonally moving to more favourable habitats as determined by more available energy and nutrients, and lower risk of predation. The causal differences between vertical and horizontal migrations as well as seasonal shifts in home range centres can be resolved by a model of habitat selection based on these factors. The densities of available digestible dry matter in Amabilis Fir - Twisted Stalk, and Mountain Hemlock - Copperbush associations are comparable with those in the shrub and conifer serai stages. This abundance of deer food in high elevation habitats suggests that forest harvesting in high elevations will not affect deer populations, if their other habitat requirements are met. In areas where forested summer ranges already exist, low elevation logging of Sword Fern - Western Red Cedar, Deer Fern - Western Hemlock, and Western Hemlock - Plagiothecium associations will provide deer with sources of abundant food closer to their winter ranges than the high elevation summer ranges. Use of these food sources may result in only a redistribution and not an increase in the deer population. Logging of Amabilis Fir - Western Hemlock, Salal - Douglas-fir, and Salal - Western Hemlock associations may be detrimental to deer populations because of their need for these habitats during winter. Management policies emphasizing preservation of severe winter range could be detrimental to deer populations. Habitat management for black-tailed deer must include provision of mild winter range as well as severe winter range. Because mild winter range provides deer with greater amounts of available energy and nutrients, it may be as important to the over-winter survival of deer as is severe winter range. The mobility of black-tailed deer and their sensitivity to snow suggest that few deer would be trapped in high elevations by early snowfalls. Corridors joining high and low elevations appear unnecessary to facilitate deer migrations. / Forestry, Faculty of / Graduate
147

Home range analysis of rehabilitated and released great horned owls (Bubo virginianus) in Denton County, Texas, through radio telemetry.

Johnston, Jennifer Lynn 12 1900 (has links)
Raptor rehabilitation has become commonplace globally, yet studies on the survival and adaptation of great horned owls (Bubo virginianus) after release has been neglected to an appreciable extent. The primary objective of this study is to provide quantitative data on the success of rehabilitated and released great horned owls in the North Texas region. Owls (N=12) were rehabilitated and released onto the Ray Roberts Greenbelt Corridor in Denton County, Texas, and monitored using radio telemetry to evaluate home range (November 2002 - February 2005). With approximately 75% of the birds released for this study surviving until transmitter battery failure, it is believed that the rehabilitation process was successful for these birds.
148

Movement ecology and spatial distribution of Tayassu pecari in heterogeneous tropical landscapes /

Oshima, Júlia Emi de Faria. January 2019 (has links)
Orientador: Milton Cezar Ribeiro / Resumo: Modificações da cobertura do solo, perturbações antropogênicas e mudanças climáticas na região Neotropical têm sido associadas à crise da biodiversidade. Nesta tese, o objetivo principal foi investigar os efeitos que a estrutura da paisagem (incluindo a perturbação antropogênica) e a qualidade do habitat têm na distribuição espacial, nos padrões de movimento e na seleção de habitat da queixada - Tayassu pecari. Esta espécie é o único ungulado florestal Neotropical que forma grandes bandos e é uma espécie-chave nos ecossistemas florestais, pois sua extinção local pode causar perdas adicionais de biodiversidade por meio de efeitos em cascata. Ainda assim, pouco se sabe sobre uso do espaço e movimentos de queixadas em escala fina. Para tanto, estudamos a distribuição e movimentação da espécie em diferentes escalas e biomas do Brasil, investigando quais variáveis de paisagem influenciaram a mesma em diferentes escalas e ordens de seleção. Nossos resultados mostram fortes efeitos negativos da modificação da paisagem e fragmentação do habitat na distribuição de queixadas, restando apenas 47% do território brasileiro com áreas adequadas para a espécie. Verificamos que menos da metade de todas as áreas protegidas nos biomas Cerrado e Mata Atlântica têm um habitat adequado para a queixada. Para a análise do movimento, rastreamos 30 indivíduos com colares de GPS de julho de 2013 a outubro de 2016 no Pantanal e no Cerrado do estado do Mato Grosso do Sul. Nossos principais resultados mos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Land cover modifications, anthropogenic disturbances and climate change in the Neotropical region have been linked to the biodiversity crisis. This thesis proposal was to investigate the effects that landscape structure (including anthropogenic disturbance) and habitat quality have in the spatial distribution, in the movement patterns and in the habitat selection of the white-lipped peccary - Tayassu pecari (WLP). This species is the only Neotropical forest ungulate that forms large herds, and it is a keystone species in forest ecosystems because its local extinction may cause additional biodiversity losses through cascading effects. Still, little is known about WLPs space use and fine-scale movement. For that aim we studied the species distribution and movements in different scales and biomes of Brazil, investigating which landscape variables would influence the species in different scales and orders of selection. Our findings show strong negative effects of landscape modification and habitat fragmentation on white-lipped peccary distribution, with only 47% of the Brazilian territory with suitable areas for the species. We also found that less than half of all protected areas in the Cerrado and the Atlantic Forest biomes have suitable habitat for WLP. For the movement analysis we tracked 30 individuals with GPS collars from July 2013 to October of 2016 in the Pantanal and in the Cerrado of Mato Grosso do Sul state. Our main results showed a positive selection of WLP for fore... (Complete abstract click electronic access below) / Doutor
149

Drivers of farmer-African wild dog (Lycaon pictus) conflict in the Waterberg Biosphere Reserve, South Africa

Dube, Lungelo January 2020 (has links)
African wild dogs (Lycaon pictus) are the most endangered large carnivore in Southern Africa. There are as little as 5,000 individuals globally and less than 450 African wild dogs in South Africa alone. African wild dogs are listed as endangered by the International Union for Conservation of Nature (IUCN) Red List. Therefore, the time has never been more crucial to conserve the species. With increased human encroachment and inhabitation in and around protected areas, so are increased conflicts between humans and carnivores. Human-wild dog conflict is likely to rise where a common resource is found. Human-carnivore conflicts have often been induced by the uncomfortably close inhabitation of humans in areas predominantly occupied by large carnivores. For this reason, it is becoming vital to establish a harmonious relationship between carnivores and humans. This research investigated the extent and causes of human-carnivore conflict specific to private landowners and the African wild dog in the Waterberg Biosphere Reserve, Limpopo Province, South Africa between April 2018 and January 2019. The causes of conflict in the Waterberg and levels of tolerance by the farmers for African wild dogs were investigated. The methodology was two-fold, using spatial analyses and an online survey. Three African wild dogs from the same pack were collared using telemetry collars (Tag 2651, Tag 2953 and Tag 3017). These data were used for the spatial analysis part of the research, using Geographic Information System (GIS) to determine the African wild dogs’ home ranges, movement patterns, and proximities to commonalities with humans and preferred land use. The private landowners possibly experiencing human-carnivore conflict were surveyed using an online survey (n = 81), and this information was used to determine the extent of conflict and tolerance of African wild dogs amongst the farmers in the Waterberg. The information gathered will be used by the Endangered Wildlife Trust to develop an early warning system for private landowners affected by the presence of free-roaming African wild dogs in the area. In general, English speaking farmers in the Waterberg Biosphere Reserve were more tolerant of African wild dogs compared with Afrikaans speaking farmers. Results also showed that areas near food and water sources are high potential conflict hotspots. The results also showed that African wild dog movement patterns in Waterberg Biosphere Reserve have an influence on conflict hotspot areas during denning season, wet and dry months, different phases of the moon, and overall hunting patterns of African wild dogs. This research facilitated an understanding of aspects of utilisation, persecution, and how to mitigate conflict between humans and African wild dogs within the Waterberg Biosphere Reserve. / Dissertation (MSc (Environment and Society))--University of Pretoria, 2020. / GreenMatter Fellowship Mapula Trust Endangered Wildlife Trust (EWT) National Research Foundation (NRF) / Geography, Geoinformatics and Meteorology / MSc (Environment and Society) / Unrestricted
150

Škálování prostorové aktivity letounů / Scaling of spatial activity in bats

Křemenová, Jana January 2016 (has links)
2 ABSTRACT The degree of spatial activity, especially the home-range size, is one of the basic biolog- ical characteristics of animals and whether it has enough resources is crucial for the survival and reproduction of the individual. Therefore, it is not surprising that many studies trying to make clear the effect of various ecological and morphological variables and explain the varia- bility of space activities. Bats are a group of mammals, for which until recently, existed only few information about their spatial activity. However, due to the miniaturization of technology and the use of radiotelemetry amount of information rapidly increasing. The aim of this study was to assemble the most complete information about the home- range size and foraging distance of bats and analyze the effect of variables that can influence the spatial activity. From published papers I collected data on 106 species representing 8 fami- lies. The influence of 6 variables (weight, wing loading, aspect ratio, food specialization, colony size, primary productivity of environment) on home-range size and average foraging distance of bat was analysed by phylogenetic regression (PGLS). The best predictor of the home-range size is the primary productivity of the environment, food specialization and body size. The best explanation of...

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