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Constrained marine resource managementMurray, Jason Hastings, January 2007 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2007. / Title from first page of PDF file (viewed October 3, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 68-72).
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Breeding Ecology and Migratory Connectivity of Passerines in the World's Southernmost ForestsJara Millar, Rocio Fernanda 05 1900 (has links)
In the extensive and remote sub-Antarctic forests of South America, birds are the dominant terrestrial vertebrates. Despite considerable efforts to understand the ecology of birds breeding in these forests, our current knowledge for many species is still incomplete. During three breeding seasons (2014 – 2017), I studied the breeding ecology of the five most abundant open-cup forest-dwelling passerines in the sub-Antarctic forest of Navarino Island, Chile (55°04′S, 67°40′W). There were differences in some of the breeding strategies used by birds breeding on Navarino Island versus conspecific populations breeding at lower latitudes. Milvago chimango was the main nest predator of open-cup nesting forest passerines, and the main cause of nest failure. In addition, I found that species built their nests in sites with higher density and taller understory; however, these two factors decreased their nest survival. This mismatch could be due to a change in depredation risk on Navarino Island, and thus, passerines breeding there may be in an ecological trap. In addition, using light-level geolocators, I determined that the migratory connectivity of Elaenia albiceps is weak as a result of the large spatial spread of individuals on the wintering ground, and that the distances among individuals on the breeding grounds are not maintained in the wintering grounds. My study opens further questions about the mechanisms driving differences in breeding strategies among populations. In addition, further research is needed to assess hypotheses that could explain the mismatch between nest-site selection and nest survival and to understand what drives elaenias' movements, not only during winter but throughout their annual cycle.
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Livestock Mortality at Beef Farms with Chronic Wolf (Canis lupus) Depredation in the Western Great Lakes Region (WGLR)Vandergon, Arion 01 December 2008 (has links)
Gray wolf (Canis lupus) depredation on beef calves has been studied extensively in recent years. As wolf populations increase throughout the United States there is a corresponding increase in wolf/livestock interactions. Most research concentrates on summaries of reported depredations and surveys of producers affected by depredations. The objective of this study was to present data on the fate of beef calves on 3 farms in Minnesota and Wisconsin over a 2-year period. Predator presence/absence was studied as an indicator of potential depredations. Also, data are presented comparing 2 techniques that may aid researchers and livestock producers with monitoring livestock. Radio telemetry collars and ear tags were applied to beef calves on 3 farms in northern Minnesota and Wisconsin during the spring and summer of 2006 and 2007. During this time, 4 calves were killed by wolves on the study farms. Wolves did not appear to be selecting the youngest calves and most depredations occurred from April through July. Although not statistically significant, wolf sign appeared at slightly higher rates on study farms than on land adjacent to these farms. Predator sign, including coyote (Canis latrans) and black bear (Ursus americanus), appeared more often in the heavily forested areas of the farms. Radio collars and radio ear tags were helpful for monitoring beef calves during this study. Radio collars had much longer transmitting distances than ear tags (2.3 ± 0.8 miles and 0.4 ± 0.2 miles, respectively). Radio ear tags had a potential for causing beef calves' ears to droop or were ripped out, possibly lowering their market value. Currently, cost is prohibitive for the widespread use of radio transmitters for monitoring livestock but as the price of new technologies decreases, transmitters may become an integral part of livestock production on farms with chronic wolf depredation.
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Faunal communities of temporary wetlands of upland and floodplain public forested lands in north MississippiEdwards, Katherine E 11 December 2009 (has links)
I conducted surveys of amphibian, reptile, and small mammal communities surrounding 4 isolated, upland and 6 stream-connected temporary wetlands on Tombigbee National Forest and Noxubee National Wildlife Refuge in north Mississippi from May 2001 - March 2006. Trap captures yielded 17 amphibian species (n = 11,142), 21 reptile species (n = 541), and 10 small mammal species (n = 472). Upland pools supported greater diversity of Ambystomatid salamanders, anurans, lizards, and mice (Peromyscus spp.), than floodplain pools. Factors including landscape position of pools, proximity to alternate water sources, and barriers to dispersal potentially influenced faunal communities of temporary wetlands. Infrared-triggered cameras were used to monitor mammalian activity surrounding ephemeral wetlands to determine potential depredation of pitfall traps. Raccoons (Procyon lotor) accounted for most images (35% total images). I assessed relative effectiveness of sampling techniques to capture and retain herpetiles in presence of depredation. I tested pitfall trap, funnel trap, and pitfall trap combined with exclusion cover along driftence arrays. Overall, pitfall traps of both designs produced more captures than funnels, and excluded-pitfalls yielded greater captures than un-excluded pitfalls for most amphibians. Overall mortality rates were <2% of total captures with anurans accounting for most (63.30%) mortality. I submit that in long-term studies, pitfall traps with exclusion are prudent to limit sampling bias and mortality occurring with depredation of captured herpetofauna. During trapping, pit-traps of both designs yielded incidental captures of small mammals. Capture rates for small mammals were similar in un-excluded pitfall traps and excluded pitfall traps. Southern short-tailed shrews (Blarina carolinensis) and mice accounted for 93% of total captures and suffered 76% and 52% mortality, respectively, potentially due to exposure, starvation, flooding, and/or depredation. Additionally, one species listed as rare in Mississippi was captured during herpetofaunal surveys, oldfield mouse (Peromyscus polionotus). Due to potential impact of pitfall trapping on small mammals, I recommend that researchers either alter trapping methods to address non-target hazards (frequency of checking traps, providing shelter) or work cooperatively using an integrated survey approach for herpetiles and small mammals to limit trap mortality.
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Déprédation par les orques (Orcinus Orca) et les cachalots (Physeter Macrocephalus) sur les palangriers à la legine australe dans la ZEE de l' archipel de CrozetTixier, Paul 10 July 2012 (has links)
C'est dans le contexte délicat du milieu marin, marqué par l'écroulement des stockshalieutiques et la conservation urgente des espèces de prédateurs marins, que s'inscrit cette étude sur la déprédation (i.e. prélèvement des poissons capturés) par les orques et les cachalots sur la pêche à lapalangre dans la ZEE de l'Archipel de Crozet.Le premier objectif a été d'évaluer les conséquences socio-économiques du phénomène. Entre 2003 et2010 les orques ont interagi avec un total de 43,3% des palangres relevées et les cachalots avec 57,5%,les deux espèces étant présentes simultanément sur 27.8% des palangres (n=5438). Les orques, seulesou associées aux cachalots ont été estimées prélever 926 ± 76 tonnes de légines sur l'ensemble de lapériode, représentant un taux de déprédation de 17,7%.Trois facteurs opérationnels ont été identifiés comme faisant varier la déprédation par les orques : i)utilisation de palangres courtes (<5000m) en absence d'orques, ii) déplacement du navire sur desdistances supérieures à 40nq pour quitter une zone confrontée à la déprédation et changer de zone, iii)utilisation de vitesse de remontée des hameçons à bord supérieures à 50 H.min-1.Le deuxième objectif de cette étude a été d'évaluer les conséquences démographiques de ladéprédation sur la population d'orques de Crozet. Le suivi à long terme des individus a permis demettre en évidence des réponses différentielles des unités sociales en fonction de leur degréd'interaction avec les pêcheries. / Over the last 50 years, fisheries have undergone a major decline worldwide. With an increasedcompetition for resource, depredation (i.e. removal of catches on fishing gear) has recently become amajor case of conflict between humans and marine predators. In this study I focused on thedepredation on Patagonian toothfish fisheries by killer and sperm whales in the Crozet EEZ. The firstpart of the study aimed at assessing the socio-economic consequences of this issue. Killer and spermwhales have interacted with 43.3% and 57.5% of longlines (n=6751) respectively from 2003 to 2010.Killer whales, alone or co-occurring with sperm whales were responsible for an estimated loss of 926± 76 tons of toothfish over that period, which represents 17.7% of the total catch.Three operational factors were identified as influencing significantly depredation levels: i) the use ofshort longlines (<5000m) in absence of killer whales, ii) the displacement of vessels on distances>40nq to leave the whales behind and iii) the use of longline hauling speed > 50 H.min-1.The second aim of the study was to investigate the consequences of depredation on the Crozet killerwhale population. The long term monitoring of individuals showed divergent demographic trajectoriesrelated to the depredation level of matrilines. During the 1990s, matrilines interacting with fisherieshave undergone a high mortality due to lethal interactions with illegal fishing vessels using explosivesto repel the whales.
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Bird Species in Urban and Agricultural Landscapes : Bird diversity patterns along an urbanisation gradient and crop damage caused by birds on the Deccan Plateau, IndiaKale, Manoj Ashokrao January 2014 (has links)
The major human activities that have transformed the Earth include agriculture and urbanization. The present study was conducted to contribute to a description of the effect on birds of urbanization and agriculture in an Indian region. Terrestrial bird assemblages were censused along a five-stage urbanisation gradient between January and April 2010-2013 near the city of Amravati, on the Deccan Plateau, Central India. Altogether, 89 species of birds were recorded, with the highest species richness in the rural areas (67 species) and lowest in the urban stage (29 species). The assemblages were significantly nested in all the five stages. Maximum cumulative species abundance (12 399 individuals over four years) was found in the urban stage, and was due to the constant presence of large groups of Rose-ringed Parakeets (Psittacula krameri). The lowest bird abundance was found in the industrial zone (4837 in total), where there was also a nearly two-fold decrease from 2010 to 2013. Thirty-six species demonstrated significant variation in their densities at least in one stage and between at least two months (p<0.05). Densities of 13.9% (n=5) of those species varied significantly in two stages, that of Copsychus saularis in three stages, and of Phoenicurus ochruros, in all five stages. Urban, suburban, periurban and forest stages were characterised by relatively stable species densities (significant changes observed only for 17.2% (n=5), 17.1% (n=6), 12.9% (n=7), and 17.8% (n=16) species, respectively). The additive diversity partitioning indicated that of the overall diversity (gamma-diversity), alpha diversity (within transects located within one stage) contributed 50.1% to the total diversity, and the controbution of within-stage variability was small (2.7%). Additionally, censuses on cultivated fields were taken. In two areas under mixed cropping systems, 53 bird species were identified in the two years period between June and December, 2011 and 2012. Out of the 53 detected species, only 14 were common (recorded at ≥50% of visits). Twenty-one species were recorded at Zadgaon in crops of tur (Cajanus cajan), cotton (Gossypium arboreum) and soybean (Glycine max). Nineteen species were recorded at Bhankhed in jawar (Sorghum bicolor), cotton and mung bean (Phaseolus aureus). At Zadgaon, territorial activity was observed in four species: the House Sparrow (Passer domesticus), Jungle Babbler (Turdoides striata), Yellow-eyed Babbler (Chrysomma sinense) and Red-wattled Lapwing (Vanellus indicus). The study indicated that four bird species were found under high risk, thirteen species at medium risk and eight species at low risk due to pesticide applications in croplands. The extent of crop damage in fields of groundnut, pearl millet, peas, sorghum, and sunflower was assessed by doing actual field censuses. The sustainable solution for reducing crop damage is a need for the farmers and such techniques will help to avoid direct or indirect effects of use of lethal bird control techniques on bird species diversity. / <p>QC 20141022</p>
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An assessment of human carnivore conflict in the Kalahari region of BotswanaKlein, Rebecca Ann January 2014 (has links)
Human wildlife conflict is a considerable conservation challenge that threatens many carnivore species worldwide and is a result of complex socio-economic and ecological processes. An understanding of the drivers of conflict is essential for any efforts to achieve coexistence. This study investigated the levels of conflict, livestock management and tolerance amongst the farming communities of the Southern and Western Kalahari in Botswana. A questionnaire survey was completed with 310 farmers throughout the region. The majority of respondents regarded coexisting with carnivores as a challenge, with losses due to depredation perceived as the greatest problem facing farmers. Conflict was widespread throughout the study area, with some spatial variations for certain species. Cattle management levels were low and while smallstock management was better, the use of improved levels of management could reduce current levels of conflict. Tolerance levels were generally low with few respondents seeing the benefits of coexistence with carnivore species. The results indicated that farm type, gender, education level, source of income, livestock numbers, location and land use all have an effect on perceived conflict and tolerance levels and strongly interact with each other. In general cattleposts were characterised by higher proportions of females, lower education levels, more benefits derived from wildlife and veld products and fewer livestock than fenced ranches. They also experienced more conflict, carried out more management and had better tolerance levels. It could be that closer connections to the land and deriving benefits from natural resources resulted in more tolerance and this is certainly worth further investigation. An improvement in the use of effective methods of livestock management, targeted environmental education programs to develop a greater awareness for the conservation value of carnivores and a diversification of livelihoods to include benefits from natural resources have the potential to reduce conflict and improve tolerance in the Kalahari region.
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Violência contra a escola: repercussões curriculares - o olhar do Conselho de Escola numa escola municipal de Santo André / Violence against school: curriculum repercussions - the School Council vision in a municipal school of Santo AndréSousa, Marli Luiza de 19 August 2015 (has links)
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Previous issue date: 2015-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This present study aims to undertake an analysis of violence situations against the school, identifying how violence is manifested in daily life and addressed in school curriculum. Therefore, we analyze the situation from a vision of segment representatives that are part of the Public Power and representatives that are part of the user population of the School Council. We also analyze the relation that user and local community establish with a municipal school of kindergarten and elementary school, located in Santo André outskirts, metropolitan region of São Paulo. We also have analyzed the possible repercussions of school violence in the curriculum of this school in question. To realize this study, we chose a qualitative approach, through documental analysis and semi-structured interviews that were applied to the School Council representatives, from researched municipal school. For documentary analysis, we used five Pedagogical Political Projects developed by the school community in the period between 2010 and 2014. The research intended to indicate possibilities of violence confrontation against the school, observed in periods that building are not used in teaching activities, from the perspective of school counselors, and in a light of some consolidated theoretical aspects of the phenomenon of violence and school curriculum. The challenges of building a curriculum that dialogues with the real problems, checking the possibility of school overcoming violence situation, manifested through vandalism and pillaging are numerous. However, it is a possible path to be trodden in an articulated form between the power public and civil society, seeking the construction of a school founded on the principle of education social quality, from access and permanence of the subjects and the democratic management of education. It was intended, with this study, offer clues to support schools in increasing their careers searching educational activities that minimize and eliminate vandalism scenes and depredation of public property from the stage of their recent histories / O presente trabalho apresenta uma análise das situações de violência praticadas contra a escola, e identifica como as ações manifestam-se no cotidiano e são abordadas no currículo escolar. Para tanto, são verificadas as situações, a partir do olhar dos representantes dos segmentos que compõem o poder público e a população usuária do Conselho de Escola, e das relações que as comunidades usuária e local estabelecem com uma escola municipal de educação infantil e ensino fundamental localizada na periferia de Santo André, Região Metropolitana de São Paulo. Analisam-se, ainda, as possíveis repercussões da violência no currículo da escola em questão. Para este estudo, optou-se por uma abordagem qualitativa, que utilizou a análise documental e entrevistas semiestruturadas, aplicadas aos representantes do Conselho de Escola da unidade pesquisada. Para análise documental, foram utilizados cinco Projetos Políticos Pedagógicos elaborados pela comunidade escolar no período de 2010 a 2014. A pesquisa pretendeu indicar possibilidades de enfrentamento da violência praticada contra a escola, observada nos períodos em que o prédio não é utilizado em atividades letivas, sob a ótica dos conselheiros escolares e à luz de algumas vertentes teóricas consolidadas sobre o fenômeno da violência e do currículo escolar. São inúmeros os desafios para a construção de um currículo que dialogue com os problemas reais com vistas às possibilidades de superação das situações de violência à escola, manifestadas por meio de vandalismo e depredação, mas é um caminho possível de ser trilhado de forma articulada entre poder público e sociedade civil, de forma a construir uma escola alicerçada nos princípios da qualidade social da educação, de acesso e permanência dos sujeitos e da gestão democrática da educação. Pretendeu-se, com o estudo, oferecer pistas para que outros equipamentos escolares possam construir suas trajetórias com ações educativas que minimizem e eliminem cenas de vandalismo e depredação do patrimônio público do palco de suas histórias recentes
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Behavioural ecology of fishermen and odontocetes in a depredation context / Écologie comportementale des pêcheurs et odontocètes dans un contexte de déprédationRichard, Gaëtan 23 November 2018 (has links)
De nombreux prédateurs marins se nourrissent directement des prises des pêcheurs. Ces interactions, définies comme de la déprédation, engendrent des conséquences socio-économiques considérables pour les pêcheurs ainsi que des implications de conservation pour la faune sauvage. D’un côté, la déprédation endommage le matériel et augmente l’effort de pêche pour atteindre les quotas. D’un autre côté, la déprédation augmente le risque de mortalité des prédateurs marins (prise accidentelle ou rétorsion létale par les pécheurs). La pêcherie à la palangre est la plus impactée par la déprédation, principalement par les odontocètes, ce qui incite à trouver des solutions. La majorité des études se concentrant sur la déprédation s’est principalement basée sur des observations en surface, de ce fait la manière dont les prédateurs retirent les poissons sur les lignes reste confuse. Par ailleurs, l’impact de la déprédation sur le comportement des pêcheurs ainsi que les facteurs expliquant leur détectabilité n’ont reçu que peu d’intérêt. L’objectif de cette thèse est donc d’étudier ces problématiques par un suivi acoustique, une utilisation de balises et une approche en écologie comportementale humaine, en se concentrant sur la pêcherie palangrière française ciblant la légine australe (Dissostichus eleginoides) impactée par la déprédation des orques (Orcinus orca) et des cachalots (Physeter macrocephalus). Les capitaines ont été décrits comme recherchant leur ressource selon la théorie de « l’optimal foraging », mais avec des perceptions de la compétition et du succès de pêche qui divergent. Certains capitaines seraient ainsi plus enclins à remonter les palangres au plus proche et à rester sur une zone, même en présence de compétition, augmentant alors le risque d’interaction. L’acoustique des navires a révélé que certaines manoeuvres (marche arrière par exemple) propagent différemment sous l’eau. La manière dont les capitaines manoeuvrent leur palangrier influencerait ainsi leur détectabilité et donc leur risque d’interaction avec les prédateurs. D’autre part, l’utilisation de capteurs sur les palangres et les animaux a révélé que les orques et les cachalots sont capables de déprédater sur les palangres posées sur le fond marin. Ces observations laissent à penser que les odontocètes sont en mesure de localiser l’activité de pêche bien avant la remontée de la ligne, ce qui pourrait être expliqué par une signature acoustique spécifique du déploiement de la ligne. L’ensemble des résultats de cette thèse suggère que la déprédation sur les palangres démersales est très probablement sous-estimée. Cette thèse apporte également des éléments importants pour la lutte contre la déprédation, en montrant la nécessité de protéger les palangres dans l’intégralité du processus de pêche. / Many marine predator species feed on fish caught by fishers directly from the fishing gear. Known as depredation this interaction issue has substantial socio-economic consequences for fishermen and conservation implications for the wildlife. Costs for fishers include damages to the fishing gear and increased fishing effort to complete quotas. For marine predators, depredation increases risks of mortality (lethal retaliation from fishers or bycatch on the gear). Longline fisheries are the most impacted worldwide, primarily by odontocetes (toothed whales) depredation, urging the need for mitigation solutions to be developed. Most of studies assessing depredation have primarily relied on surface observation data, thus the way odontocetes interact with longlines underwater remains unclear. Besides, the way fishermen respond to depredation during fishing operations, or can influence their detectability to odontocetes, have been poorly investigated. This thesis therefore aimed at investigating these aspects through a passive acoustic monitoring, bio-logging and human ecology approaches, focusing on the French Patagonian toothfish (Dissostichus eleginoides) longline fisheries impacted by killer whales (Orcinus orca) and sperm whales (Physeter macrocephalus). Firstly, this thesis reveals that captains behave as optimal foragers but with different personal perception of competition and fishing fulfilment. Some captains would thus be more likely to stay within a patch or to haul closest longline even in presence of competition, suggesting these captains would show higher interaction rates. Additionally, the propagation of vessels’ acoustics varied depending on the type of manoeuvre (e.g. going backward vs. forward). The way captains use their vessels to navigate may therefore influence their detectability and so their depredation level. Secondly, loggers deployed on both the longlines (accelerometers) and odontocetes (GPS-TDR) revealed that killer whales and sperm whales are able to depredate on longlines while soaking on the seafloor. These observations suggest, therefore, that odontocetes can localise fishing activity before the hauling, which could be partially explained by specific acoustic signatures recorded during the setting process. Altogether, the results of the thesis suggest that depredation rates on demersal longlines are most likely underestimated. The thesis also brings some important insights for mitigation measures, suggesting that countermeasures should start from setting to hauling.
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History From the Heart: Difficult Pasts and Possible Futures in the Heterogeneous Doukhobor Community in CanadaWhite, Sonya 31 May 2011 (has links)
This thesis shares the results of oral history interviews with members of the heterogeneous Doukhobor community in Canada. The stories and memories of fifteen different voices highlight the influence of intersecting demographic variables (age, gender, ideological affiliation, and geographic location) on the experience of Doukhobor life in Canada during times of sensationalized conflict. The interviews are framed and analyzed through broader questions of history and cultural sustainability. What considerations influence the representation of difficult Doukhobor pasts in Canada? In the contemporary context of unification and reconciliation, how does one speak of conflict?
This thesis shows that discussions of the past surface considerable contradiction in the collective memory of the Doukhobor community; the results outline various individual and community strategies that are used to manage the past in favour of the present. Ultimately, this thesis locates memory as a social and cultural anchor that must support a history for the future.
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