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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.
351

Avaliação dos aspectos relacionados à criação e manejo de reservas particulares do patrimônio natural no Estado do Mato Grosso do Sul, Brasil / Evaluation of aspects related to creation and managment of private reserves of natural heritage in Mato Grosso do Sul State, Brazil

Pellin, Angela 21 May 2010 (has links)
A criação voluntária de áreas protegidas privadas está em expansão ao redor do mundo, sendo reconhecida como uma importante estratégia para conservação da biodiversidade e complemento dos esforços públicos de conservação. No Brasil, estas áreas são chamadas Reservas Particulares do Patrimônio Natural (RPPNs), áreas criadas em caráter perpétuo, por iniciativa de seus proprietários e reconhecidas pelo poder público. No entanto, apesar de já existirem mais de 930 RPPNs que protegem 680.000 ha no país, ainda existe uma lacuna de informações sobre o tema. Esse trabalho pretende contribuir para diminuição desse problema, utilizando como área de estudo o Estado do Mato Grosso do Sul. Seus objetivos foram identificar as motivações dos proprietários ao solicitarem a criação dessas unidades, os incentivos e dificuldades enfrentadas para criação e gestão, e caracterizar essas áreas e a eficácia da sua gestão. Para isso, seus proprietários ou gestores foram entrevistados e foram consultados os processos de solicitação de criação dessas áreas e outros documentos fornecidos pelos proprietários. Para a avaliação do manejo, foi necessária a adaptação da metodologia de Cifuentes, Izurieta e Faria (2000) para o contexto das áreas analisadas. Ao todo, foram identificados 65 processos de solicitação de RPPNs, mas apenas 36 áreas são efetivamente reconhecidas atualmente. O tempo de tramitação dos processos de reconhecimento tem sido alto e é influenciado pelos procedimentos institucionais, pelo rigor das exigências documentais e pelo número de pendências existentes. As entrevistas com os responsáveis pelas RPPNs demonstraram que estes consideram o processo de criação lento e burocrático. A conservação é a principal motivação para sua criação, mas fatores econômicos e pessoais também são citados. O único incentivo oferecido pelo poder público é a isenção do imposto territorial rural. Outros incentivos para a criação e gestão destas áreas têm sido dados por ONGs e a Associação de Proprietários de RPPN, principalmente na região da Bacia do Alto Paraguai. A conservação e a pesquisa são objetivos de manejo de todas as RPPNs, mas a educação ambiental e turismo também são bastante citados. Com relação à avaliação do manejo, o conjunto de RPPNs obteve 57,6% do total ótimo possível. Mais da metade das áreas foi classificada como gestão muito inferior ou inferior, 17,6% como mediana, e 29,4% como padrão elevado ou de excelência. Os âmbitos mais bem avaliados foram usos atuais e político e legal; os piores foram o planejamento e ordenamento e o conhecimento. Entre os pontos fortes do conjunto estão: compatibilidade das suas atividades com as normas, reconhecimento legal, porcentagem de área alterada, e demarcação física. Entre os pontos mais fracos estão: monitoramento e retroalimentação, tamanho, programas de manejo, informações e plano de manejo. A proteção parece ser uma das maiores preocupações dos proprietários, que de forma geral, parecem reconhecer as principais fragilidades destas unidades. / The voluntary creation of private protected areas has rapidly increased around the world and it has been recognized as an important strategy for biodiversity conservation, adding public efforts to conservation. In Brazil, these areas are called Private Reserves of Natural Heritage (PRNHs), and they are created for perpetuity, by their owners\' initiative, and recognized by the public administration. However, despite the fact that there are already over 930 PRNHs, which are protecting around 680.000 ha in the country, there is still lack of information concerning this topic. This work intends to address this problem, using the case of Mato Grosso do Sul State. The main objective is to identify the owner\'s motivations for the establishment of PNHRs, the driving forces and the difficulties faced by their recognition and management, as well as to characterize these areas and their management effectiveness. To that purpose, the owners or managers were interviewed. There has been also documental analysis and the documents for the application of these areas\' establishment and other related documents provided by the owners were consulted. For the management evaluation, an adaptation of the Cifuentes, Izurieta and Faria (2000) methodology was necessary for analyzing the areas context. In the overall, 65 applications for the establishment of PNHRs were identified, but only 36 areas are currently effectively recognized. The procedural time for the establishment process has been high, and it is affected by institutional procedures, several documentation requirements, and by the lack of required documentation. The interviews with owners and managers showed that they think the processes are slow and bureaucratic. The conservation is the main motivation for their creation, but economic and personal factors were also mentioned. The only incentive offered by the government was the rural property tax exemption. On the other hand, NGOs and the PNHR Owners\' Association have encouraged the creation and management of these areas, mainly for the High Paraguay Basin. Conservation and research are management objectives of all PNHRs, but environmental education and tourism are also fairly mentioned. Regarding management evaluation, the group of PNHRs reached 57,6% of the total possible optimum. More than half of the areas had management classified as very inferior or as quality inferior standards, 17,6% as medium, and 29,4% as high or excellency standards. The set of indicators best evaluated were current uses and political and legal. The worst set of indicators were planning and instructing and knowledge. The strength issues of the group are: the compatibility of their activities with legislation, legal recognition, percentage of disturbed area, and physical demarcation. The weakest points are: monitoring and feedback, size, management programs, information and management plan. The protection of these areas seems to be a major concern for their owners, who usually seem to recognize the main weaknesses of these protected areas.
352

Land Use, Diverse Values, and Conservation Practice in the Periphery of Makira Natural Park, Northeastern Madagascar

Cullman, Georgina January 2013 (has links)
This dissertation examines the intent and reality of a conservation project that aims to be participatory and to provide benefits to local landholders. I make a contribution to research about the social impacts of conservation projects as well as to scholarship that aims to improve conservation policy and practice. Using both ethnographic and ecological methods, I explored the multiple and contested values related to land use. Changing local land use practices, especially reducing swidden agriculture, is a major focus of conservation interventions in the region. The conservation project has framed this change as a technical problem, and has devised economic incentives to shift local people's land use. Because of the dissertation's interdisciplinary approach, and the sometimes contentious relations between conservation biologists and practitioners and social scientists, I begin with a review of the challenges to achieving interdisciplinary collaboration. In the second chapter, I seek to understand how a government policy that was meant to benefit forest-dwelling communities was instead experienced as disempowering and restrictive. Chapter 3 uses land-use scenarios to evaluate the multiple objectives of Makira Natural Park (i.e., biodiversity conservation, climate change mitigation and sustainable livelihoods support) through the lens of ecosystem services, concluding that the best strategy to meet Makira's multiple objectives is to support a broad diversity of land use types rather than eliminating some and favoring others. In Chapter 4, I demonstrate how the conservation project's reliance on an economic model of human motivation to shift land use practices relies on a set of values that are not necessarily shared by local landholders, which explains in part their lack of traction to date. I conclude with a series of recommendations for how to transform conservation practice in Makira to make it more effective, culturally appropriate, and just.
353

Ecological and Genetic Variation Among Populations of <em>Boechera caeruleamontana</em> sp. nov. (Brassicaceae) from Blue Mountain and Dinosaur National Monumentin Eastern Utah and Western Colorado

Snyder, Melissa 01 April 2017 (has links)
Boechera is a large genus of flowering plants whose taxa are found primarily in North America. Boechera vivariensis (S.L. Welsh) W.A. Weber (the Park rockcress) is restricted to the Uintah Basin on Weber sandstone substrates in the vicinity of Dinosaur National Monument and Blue Mountain. The nomenclature of Park rockcress is significantly impacted by the discovery that the type collections of the taxon represent a rare, apomictic diploid resulting from the hybridization between B. thompsonii and an undescribed sexual diploid (to be called Boechera caeruleamontana sp. nov. Allphin and Windham). As a result, greater information is needed regarding how B. vivariensis and B. caeruleamontana. are distributed geographically in the region of Dinosaur National Monument and surrounding areas. Thus, we performed genetic analyses on leaf samples taken from over 50 individuals at known sites of B. vivariensis throughout its geographic range. Individuals from each site were also compared morphologically. We also compared associated plant communities at each site and characterized the soils. In our thorough sampling, we did not pick up B. vivariensis. All individuals sampled belonged to B. caeruleamontana, suggesting that most individuals previously assigned to B. vivariensis, are actually representative of B. caeruleamonanta. Populations of B. caeruleamontana were genetically diverse compared to other Boechera species, most likely indicative of its insect pollination strategy. However, all populations had lower heterozygosity than expected based upon Hardy-Weinberg expectations. Reproductive and genetic data indicated that populations are showing signs of inbreeding. The population at Jones Hole Fish Hatchery was most unique genetically, morphologically, and reproductively.
354

Light pollution & biodiversity : What are the levers of action to limit the impact of artificial lighting on nocturnal fauna ? / Pollution lumineuse & biodiversité : Quels leviers d'actions pour limiter l'impact de l'éclairage artificiel sur la faune nocturne ?

Pauwels, Julie 11 October 2018 (has links)
L’emprise de la lumière artificielle s’étend de manière importante et rapide à travers le monde entier et est en train de changer le paysage nocturne menaçant ainsi une large part des écosystèmes. L’augmentation des niveaux de lumière la nuit entraîne une perturbation du rythme circadien et par là une modification des comportements des espèces nocturnes mais aussi diurnes et des interactions entre espèces. Malgré l’importance de l’enjeu que représente la pollution lumineuse, le manque de connaissances dans le domaine limite la création de réglementations pour réduire l’impact de l’éclairage nocturne sur la biodiversité. Il est donc urgent d’apporter des éléments concrets pour construire des recommandations et des outils d’évaluation à destination des gestionnaires du territoire.Dans ce contexte, l’objectif de cette thèse est d’étudier l’impact de la pollution lumineuse sur la faune nocturne à deux échelles paysagères afin de préconiser des méthodes d’évaluation et de gestion de l’éclairage artificiel. Nous avons utilisé les chauves-souris comme modèle d’étude car elles sont longévives et nocturnes et donc fortement affectées par la pollution lumineuse. De plus, il a été montré que les tendances de leurs populations tendent à refléter celles d’espèces plus basses dans la chaîne trophique, les rendant ainsi d’autant plus sensibles aux pressions anthropiques. Dans un premier temps, nous avons étudié l’effet de la pollution lumineuse à l’échelle de villes, une échelle paysagère en cohérence à la fois avec les distances de déplacement des individus et avec une réalité de gestion de l’éclairage. Malgré que les espèces anthropophiles vivant toujours dans les grandes villes soient considérée comme bénéficiant de l’éclairage artificiel, ce travail a montré qu’à une échelle regroupant tous les aspects des déplacements quotidiens des individus, l’effet global de la lumière est négatif. De plus, bien qu’une part significative de la pollution lumineuse soit due à l’éclairage public de par sa permanence et son étende, l’étude montre que l’éclairage privé n’est pourtant pas à négliger. Au-delà d’un effet sur le niveau d’activité, la lumière artificielle peut avoir un effet de barrière dans le déplacement des individus et ainsi réduire la connectivité du paysage. Alors que les politiques environnementales sont en faveur du développement de corridors écologiques, la non-inclusion du facteur pollution lumineuse pourrait réduire significativement leur efficacité pour les espèces nocturnes. Un travail de modélisation mettant en lien des données biologiques d’activité avec des aspects paysagers mais aussi lumière a permis de construire des corridors adaptés pour les espèces nocturnes. Cela a aussi mené à des outils d’évaluation de scénarios d’éclairage qui peuvent être utilisés en amont d’aménagements afin de prédire l’impact d’un changement et de les adapter aux enjeux de biodiversité. A une échelle plus fine, il est nécessaire de comprendre quelles caractéristiques des points lumineux sont les plus pertinents à maîtriser afin de formuler des recommandations pour limiter l’impact sur la biodiversité. Nous avons mené une étude de terrain dans un espace protégé où les enjeux sur les chauves-souris sont d’autant plus importants que les espèces les plus sensibles à la lumière y sont protégées, ainsi que leurs habitats, à l’échelle européenne. En travaillant à l’interface entre urbanisation et habitats semi-naturels, nous avons pu montrer que c’est la quantité de lumière émise qui ont l’effet le plus notable. C’est donc ce paramètre sur lequel il faut travailler en priorité pour limiter l’impact de la lumière sur des zones pouvant servir de corridor ou de zone refuge aux espèces sensibles. / The spatial extent of artificial light is increasing rapidly and significantly on Earth surface hence changing the nocturnal lightscape and threatening an important part of ecosystems. The rise in nighttime light levels induces a perturbation of the circadian rhythm and thus a modification of nocturnal, but also some diurnal, species behavior and interactions between species. Despite the spread of light pollution being of major concern, the knowledge gaps in this field limit the creation of regulations to reduce the impact of nighttime lighting on biodiversity. Therefore it is urgent to produce clear and practical information to build tools and define recommendations for land managers. In this context, the aim of the PhD thesis is to study the impact of light pollution on nocturnal fauna through two spatial scales in order to propose methods to evaluate and manage artificial light. We used bats as a model species as they are long-lived and nocturnal and thus highly impacted by light pollution. In addition, it has been shown that their population trends tend to reflect those of species lower in the trophic chain which makes them even more sensitive to anthropic pressures. First, we studied the effect of light pollution within cities. This spatial scale is both coherent with bats distance of movement and with the reality of public lighting management. Although some urban-adapted species living within large cities are considered to benefit from artificial light, this work showed that, at a scale including all aspects of bats daily travels, light has a negative effect on bats activity level. Also, even if a large part of light pollution is due to public lighting, the results show that private lighting should not be neglected. Beyond the impact on bat activity, artificial light can have a barrier effect when individuals are transiting and thus reduce the landscape connectivity. Whereas environmental policies are promoting the development of ecological corridors, not considering light pollution could significantly reduce their efficiency for nocturnal species. Modelling the link between biological data and landscape variables including light level allowed us to build adapted corridors for nocturnal species. This lead to the development of a tool to evaluate lighting scenarios that could be used prior to the implementation of a lighting plan in order to predict the impact it would have and hence adapt it to the local biodiversity issues. At a finer scale, it is necessary to understand which light characteristics are the most relevant levers of actions to formulate recommendations to limit light pollution impact on biodiversity. We carried a field work experiment in a protected area where conservation issues on bat species are even higher as the species most sensitive to light are protected there, together with their habitat, at the EU level. We worked at the interface between urban and semi-natural areas and showed that the illuminance was the most important light characteristic. Hence it is on this parameters that regulations should be applied in priority to limit the impact of light on areas that could potentially be used as corridors or dark refuges for sensitive species.
355

Spatial vegetation ecology: Understanding the ecosystem processes that influence plant diversity patterns at different spatial scales / Habilitationsschrift

Culmsee, Heike 17 February 2015 (has links)
No description available.
356

The Effects of Habitat Parameters on the Behavior, Ecology, and Conservation of the Udzungwa Red Colobus Monkey (Procolobus gordonorum)

Steel, Ruth January 2012 (has links)
<p>A central theme in animal ecology is the study of the relationship between ecology and behavior. This dissertation demonstrates how ecological parameters, particularly food and weather variables, correlate with ranging, activity budget, and diet in Udzungwa red colobus monkeys (URC, <italic>Procolobus gordonorum</italic>), endemic to the Udzungwa Mountains, Tanzania. </p><p> From April 2009 - March 2010, four URC groups were habituated and studied in Mwanihana and Magombera Forests. During all-day follows, ranging, activity budget, and diet data were collected using GPS units and ten-minute scan samples of sustained activities. Food characteristics were assessed using transect and phenology surveys. Preliminary nutritional analyses were conducted on species-specific parts fed upon during October. I designed and employed novel methods for estimating ranging statistics which were compared with conventional methods.</p><p> Home range sizes were relatively small (8.8 - 20.8 ha). Home range size may relate to food species diversity and feeding selectivity for species-specific food parts. Variability in dietary composition was partly explained by plant phenology, forest composition, and selectivity differences among groups. URC primarily fed upon young leaves with higher fat content. Some non-nutritive items eaten may function as detoxifying agents. Data suggest that the URC dietary strategy involves nutrient balancing (i.e. maximizing energetic intake and nutrient acquisition while avoiding high concentrations of particular plant secondary compounds).</p><p> Mean daily travel distance (DTD) was 970 m, longer than in other red colobus taxa. DTD was shorter in October and November when temperatures were warmer and a high abundance of young growth became available. Young growth comprised the majority of all groups' diets in each sample period. When young growth abundances were highest, Magombera groups traveled shorter distances. One group's DTD did not differ seasonally and was significantly longer compared to other groups. This group may have traveled longer distances and spent less time resting in order to consume young growth in a habitat with lower young growth abundances. A correlation between time spent resting and temperature suggests behavioral prevention of hyperthermia. URC energetic strategies may involve balancing thermoregulation with maximizing energy intake. Conservation recommendations are discussed and include stricter forest protection.</p> / Dissertation
357

Spatial variation in tree community assembly

Lasky, Jesse Robert 14 November 2013 (has links)
Spatial variation in tree community composition and assembly is due in large part to dispersal limitation, spatial variation in environmental conditions, and interactions among competing trees. The relative importance of these processes may be governed by landscape structure and environmental conditions. (I) The movement of frugivores between remnant forests and successional areas is vital for tropical forest tree species to colonize successional habitats. I found that avian frugivores crossing forest edges were generally insensitive to percent cover and clustering of pasture trees. If pastures were abandoned the distance from forest edges would not likely limit frugivore visitation and seed deposition under pasture trees in my study. (II) Relatively little is known from a theoretical conservation perspective about how reserve size affects communities assembled by abiotic and dispersal limitations. Simulated small reserve systems increased the distance between environments dominated by different species, diminishing the importance of source-sink dynamics. I found a trade-off between preserving different aspects of natural communities, with greater [alpha]-diversity in large reserves and greater [gamma]-diversity across small reserve systems. (III) Functional trait diversity of co-occurring organisms may be indicative of the processes that structure communities. Across spatial scales, an axis of leaf succulence exhibited the strongest evidence for niche-based assembly among co-occurring Ficus individuals, whereas specific leaf area (SLA) showed the strongest evidence for niche-based assembly among species. Trait analyses of co-occurring individuals had greater power than analyses at the species level, especially for traits with high intraspecific variation. Environmental filtering may be stronger at higher elevations due to drought stress. (IV) Individual fitness is a function of the interaction between traits and environment, or environmental selection. I estimated spatial selective gradients affecting a subtropical tree community and found that the trait axes with the strongest selection were also those with the least spatial variation. Interestingly, factors associated with selection were quite different for growth versus survivorship. The trait-by-environment interactions I identified are strong candidates for spatial niche differentiation, and may explain how tree species coexist in this diverse subtropical forest. / text
358

On the dynamic management of marine resources

Dunn, Daniel Carl January 2014 (has links)
<p>Mismatches in the spatiotemporal variability of resource, resource users and management actions breeds inefficiency in the management of marine resources. To date, the spatiotemporal resolution and extent of fisheries management has been largely dictated by logistical and political constraints, and secondarily by the geographic range of the species or meta-population dynamics. Management units are rarely smaller than 1000 km2 in developed coastal fisheries, and management measures generally occur at resolutions larger than 100 km2. From a temporal perspective, the finest resolution of management measures is at best a month but more generally a year. As such, attempts to manage processes and patterns at sub-10 km, sub-1 month resolution often involve some level of spatiotemporal mismatch. To address the obvious spatiotemporal mismatch between a dynamic ocean and static management, to allow for a comprehensive implementation of ecosystem-based fisheries management, and to minimize inefficiency in our management of marine resources, we must seek to develop more dynamic management measures that allow managers to address scales, processes and patterns occurring under ten kilometers.</p><p>In this dissertation I apply point pattern processes, cumulative distribution functions, receiver operator characteristic curves, simulated annealing tools, regression models and clustering techniques to develop examples of two dynamic management measures and to compare the efficiency of static versus dynamic management measures. I show that autocorrelation analysis can inform the distances and times used in real-time closures based on move-on rules. Further, I identify optimum bottom temperature threshold values to separate individual species within the Northeast Multispecies Fishery from Atlantic cod. Results demonstrate that dynamic spatiotemporal management measures are widely applicable, and more effective and more efficient than static time-area closures. Unexpected trends in some results due to a changing climate indicate possible increasing thermal overlap between Atlantic cod and many other species in the fishery. Implications of scale in fisheries management and the importance of coarse scale (1 - 10km) ecological patterns to fisheries are discussed.</p> / Dissertation
359

Evaluating and Predicting Ecosystem Services

Kadykalo, Andrew 10 September 2013 (has links)
The valuation of ecosystem services requires first and foremost, that the current level or stock of a service first be estimated. Here, I investigate the relationship between the fields of environmental science and ecological economics in their research effort of ecosystem services and the implications this may have on the ecosystem valuation research program. I investigate two ecological functions described as ecosystem services within specific ecosystem types: the flood control provisioning services of wetlands and pollination service provisioning by pollinator populations in agroecosystems. I examined the environmental literature to provide quantitative estimates of a) the distribution of the level of service delivered as well as b) the ability of environmental scientists to predict this level of service. The results presented here suggest a moderately strong correlation between research efforts in environmental science and ecological economics at the pooled level of ecosystem types and services. I suggest however, an integrated research enterprise between social and environmental scientists may provide greater efficiency by means of a global ecosystem service research network and repository. I found that, on average, consistent with conventional wisdom, wetlands do indeed have a positive effect by reducing the frequency and magnitude of floods, increasing low flows, and increasing water storage. In the same vein, I found on average and consistent with conventional wisdom, there is a consistent and comparatively strong association between pollinator abundance and agroecosystem productivity as inferred from measures of plant fertilization success. In both investigations however, metaregression analysis indicated that our current ability to predict either pollination or flood control services is poor to modest at best. The low predictive power combined with the observed heterogeneity in effect size in both investigations suggest that flood control service delivered by wetlands or pollination services delivered by natural pollinator populations in agroecosystems and the expected changes in the level of services delivered under a candidate management scenario, will have a large uncertainty. Such uncertainty should be explicitly incorporated into estimates of both the current economic value of ecosystem services, as well as estimates of how these values are likely to change under alternative management scenarios. Given these, I suggest that the implications for the development of Market-based instruments (MBIs) or any payment of ecosystem services to conserve ecosystem services: that the associated ecological function(s) must be few and well characterized, and we must agree on what endpoints ought to properly be used to characterize these functions. If this condition is not met, an ordinal ranking is the best we can do and in the absence of obvious enthusiasm for more detailed scientific research which leads to the conclusion that perhaps alternate strategies like command and control may be the better alternative to protect ecosystem services.
360

Patterns and processes of marine habitat selection: foraging ecology, competition and coexistence among coastal seabirds

Ronconi, Robert Alfredo 13 May 2008 (has links)
Changes in the marine ecosystem can affect the distribution, survival, and reproductive success of seabirds. Therefore, a better understanding of factors influencing the marine distribution and abundance of seabirds can provide insight into ecological hypotheses and have important conservation implications. Yet at-sea habitat selection by seabirds has received far less attention than have investigations of their breeding biology. I studied the patterns and processes of marine habitat selection by seabirds in nearshore waters of Pacific Rim National Park Reserve, Vancouver Island, British Columbia. The study focused on comparative analyses among five sympatric species: marbled murrelet (Brachyramphus marmoratus), common murre (Uria aalge), rhinoceros auklet (Cerorhinca monocerata), pigeon guillemot (Cepphus columba) and pelagic cormorant (Phalacrocorax pelagicus). I used a multi-scaled and multi-disciplined approach combining shore-based telescope observations, vessel-based surveys, and developed new techniques for mapping nearshore seabird distributions. Patterns of habitat selection were examined through vessel-based surveys and species-habitat modeling. Vessel-based transects are fundamental to studies of seabird ecology, yet standardized protocols often fail to account for detectability biases. Distance-sampling methods were used to quantify seabird detectability along transects and showed extensive variability (20-80% of birds detected) depending on species, year, and observer. Corrected estimates of bird densities were used in habitat selection modeling, which demonstrated inter-specific and inter-annual differences in species-habitat associations. Most species showed distinct partitioning in habitats, particularly with respect to substrate and along gradients of depth and sea-surface temperature/salinity. Thus, environmental variability is a key factor structuring habitat use and coexistence in this community of piscivorous seabirds. Processes of habitat selection were studied through observations of foraging behaviour, estimates of prey availability, and spatial-statistical analysis of seabird distributions. Marbled murrelets increased foraging effort in years and seasons with scarce prey and poor oceanographic conditions and decreased foraging effort at sites with high prey availability. Despite their flexible activity budgets, increased foraging effort was inadequate to buffer reproductive success in a poor prey year, suggesting that prey availability is a limiting factor in habitat use and population growth for murrelets. Theodolite-based mapping studies examined the fine-scale distribution patterns of murrelets and murres. Nearest neighbour spatial statistics tested for competition over foraging space and showed avoidance of murres by murrelets. The results of these studies have implications for the management and conservation of the imperiled marbled murrelet in British Columbia and elsewhere in their range. I demonstrate a clear link between prey availability and consequences for reproductive success. Habitat selection models provide a step towards identifying critical marine habitats which must be protected under the Species at Risk Act. Murrelets show high forage site fidelity and associations with spatially fixed habitat components (beaches), suggesting that marine protected areas may have an important role to play in the conservation, management and recovery of murrelet populations.

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