3,122 research outputs found

    Hydrographic Features, Cetaceans and the Foraging of Thick-billed Murres and Other Marine Birds in the Northwestern Barents Sea

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    The at-sea distribution of thick-billed murres (Uria lomvia) in southeastern Svalbard waters was studied during the summers of 1992, 1993, and 1996. The Storfjordrenna region south of Svalbard was confirmed as an important foraging area for thick-billed murres; murre aggregations were located at distances of 85 to 126 km from the closest breeding colonies. Fish, mainly polar cod (Boreogadus saida), but also capelin (Mallotus villosus), were the main prey found in 16 murres and 3 black-legged kittiwakes (Rissa tridactyla) collected from these aggregations. Murres were seen flying with fish in their beaks at four locations 78 to 102 km away from the colonies. Murre aggregations were associated with frontal zones between cold Arctic waters and warmer Atlantic water, and in areas with strong stratification in salinity at 15-30 m. A positive association was found between the abundance of murres and the occurrence of cetaceans. Murres and other marine birds were often seen near surfacing cetaceans. The most common cetaceans were minke whales (Balaenoptera acutorostrata) and white-beaked dolphins (Lagenorhynchus albirostris).Durant les étés de 1992, 1993 et 1996, on a étudié la distribution en mer de la marmette de Brünnich (Uria lomvia) dans les eaux du sud-est du Svalbard. La région Storfjordrenna au sud du Svalbard a été confirmée comme une zone importante de collecte pour la marmette de Brünnich; des concentrations de marmettes étaient situées à des distances allant de 85 à 126 km des colonies nicheuses les plus proches. Le poisson, en particulier la morue polaire (Boreogadus saida), mais aussi le capelan (Mallotus villosus), était la proie principale trouvée chez 16 marmettes et 3 mouettes tridactyles (Rissa tridactyla) prélevées dans ces concentrations. On a vu les marmettes voler avec du poisson dans leur bec à quatre endroits éloignés de 78 à 102 km des colonies. Les concentrations de marmettes étaient associées à des zones frontales entre les eaux froides de l'Arctique et l'eau plus chaude de l'Atlantique, et dans des régions ayant une forte stratification dans la salinité à une profondeur de 15 à 30 m. On a trouvé qu'il existait une association positive entre l'abondance des marmettes et la présence des cétacés. On voyait souvent les marmettes et d'autres oiseaux marins près des cétacés qui faisaient surface. Les cétacés les plus communs étaient les petits rorquals (Balaenoptera acutorostrata) et les dauphins à nez blanc (Lagenorhynchus albirostris)

    SeaCycler: A moored open-ocean profiling system for the upper ocean in extended self-contained deployments

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    The upper ocean, including the biologically productive euphotic zone and the mixed layer, has great relevance for studies of physical, biogeochemical, and ecosystem processes and their interaction. Observing this layer with a continuous presence, sampling many of the relevant variables, and with sufficient vertical resolution, has remained a challenge. Here a system is presented which can be deployed on the top of deep-ocean moorings, with a drive mechanism at depths of 150-200m, which mechanically winches a large sensor float and smaller communications float tethered above it to the surface and back down again, typically twice per day for periods up to 1 year. The sensor float can carry several sizeable sensors, and it has enough buoyancy to reach the near surface and for the communications float to pierce the surface even in the presence of strong currents. The system can survive mooring blow-over to 1000m depth. The battery-powered design is made possible by using a balanced energy-conserving principle. Reliability is enhanced with a drive assembly that employs a single rotating part that has no slip rings or rotating seals. The profiling bodies can break the surface to sample the near-surface layer and to establish satellite communication for data relay or reception of new commands. An inductive pass-through mode allows communication with other mooring components throughout the water column beneath the system. A number of successful demonstration deployments have been completed

    Integrative systems methodology: Heuristic for requisite variety

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    Recreation, tourism and nature in a changing world : proceedings of the fifth international conference on monitoring and management of visitor flows in recreational and protected areas : Wageningen, the Netherlands, May 30-June 3, 2010

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    Proceedings of the fifth international conference on monitoring and management of visitor flows in recreational and protected areas : Wageningen, the Netherlands, May 30-June 3, 201

    Humpback whale habitat use patterns and interactions with vessels at Point Adolphus, Southeastern Alaska

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    Thesis (M.S.) University of Alaska Fairbanks, 2006Humpback whales at Point Adolphus, in southeastern Alaska, are faced with the challenge of maximizing their energy gain from feeding and minimizing energy losses that can occur due to disturbance by vessel traffic. Point Adolphus is unique because of abundant prey resources that attract high concentrations of humpback whales during the summer and high levels of vessel activity. Using scan sampling and focal behavior observation sessions data were collected from an elevated shore station on the northern coast of Chichagof Island in 2001. Humpback whale numbers peaked during early ebb tide. Whales were distributed west during ebbing tides and east during flooding tides. During flood tides, humpback whales exhibited non-directional movement. Differences in humpback whale numbers, distribution and movement patterns in relation to tide appeared related to small-scale fronts and headland wake effects associated with Point Adolphus. Overall, humpback whale swimming speeds were faster when the number of vessels present was greater and distance to the nearest vessel was smaller. However, responses of individual whales differed. Humpback whales at Point Adolphus appear to have developed strategies to exploit predictable times to feed which are tidally-induced and practice short-term avoidance strategies that may reduce the effects of vessel traffic

    Literature Teaching in EFL Context: Some Issues and Dilemmas

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    Using literature instruction practices in different “literature programs” as a point of departure, this article discusses some knotty issues and dilemmas confronting English literature instructors and researchers in Indonesia, especially those working in the context of English as A Foreign Language (EFL). First some commonly adopted approaches to literature teaching are outlined and specific issues and dilemmas located. Next, using the Indonesian current situation as a case in point, these perceived issues and dilemmas are fleshed out and possible solutions from diverse fronts are then sketched out

    Democratizing Energy, Energizing Democracy: Central Dimensions Surfacing in the Debate

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    This perspective piece sets to contribute to the academic and practitioner debates around energy democracy in the age of climate crisis. In tackling the present-day energy transition challenges in a democratic, equitable, just and sustainable manner, we argue that sound research shall take alternative currents to centralized access to and control of energy decision making at its core as well as exploring new and novel ways to deal with production and distribution issues. Critical research on new actors, materialities, values, worldviews, democracy, and justice on energy is well-situated to meet these challenges. Navigating value systems, exploring enabling or disabling material qualities, focusing on ruptures, continuities, and emerging new geographies all carry a promise in critical energy research. We contend that ‘normative, political and embodied’ research strategies must be used to defeat the far right’s the particularly mischievous approach to planetary futures.Peer ReviewedPostprint (published version

    What If? The Art of Scenario Thinking for Nonprofits

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    Gives an overview of scenario thinking customized for a nonprofit audience. Outlines the basic phases of scenario development, and provides examples and advice for putting the process into practice. Includes an annotated bibliography of select readings

    Manned submersible „JAGO“

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    The manned submersible „JAGO“ is a human occupied underwater vehicle (HOV) designed for personal exploration and research in all types of aquatic systems and habitats. The seafloor along the continental shelf and slopes within the ocean twilight zone is JAGO’s main target area. The DNV-GL classed 2-person submersible has a maximum operating depth of 400 m. The two occupants, the pilot and one observer, are seated at 1 Atmosphere in a steel pressure hull with two large acrylic windows. The submersible’s small size and lightweight construction (3 T) allows worldwide operations from on board a wide variety of vessels as well as transport in a single standard 20-foot container together with all support equipment. Typical applications include personal observation of the sea bed and water column, video and photo documentation, selective non-intrusive sampling, placement of sensors and experiments, underwater inspection, as well as location and recovery of object
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