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Showing 1 to 19 of 19 for “"Antarctic krill"”.
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The spatial distribution of Antarctic krill (Euphausia superba Dana) aggregations
In nature, many biota exhibit recognisable spatial groupings, commonly termed "clumps" or "patches" (Hutchinson 1953; Diggle 1983; Wilson 1978). Attempts to devise measures of such aggregation are usually based on statistically determining the frequency distributions of selected organism parameters …
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Modeling Studies of Antarctic Krill (<i>Euphausia superba</i>) Survival During Transport Across the Scotia Sea and Environs
<p>The Antarctic krill (<em>Euphausia superba</em>) populations at South Georgia, which is in the eastern Scotia Sea, are hypothesized to be sustained by import of individuals from upstream regions, such as the western Antarctic Peninsula. To test this hypothesis a modeling framework consisting of …
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Ecosystem impacts of variable recruitment in Antarctic krill investigated with long-term monitoring and archived ADCP backscatter data
… impacts of anthropogenic climate change on the krill-reliant marine ecosystem of the western Antarctic Peninsula. I use long-term ecological monitoring data to examine the impact of highly variable krill recruitment on a krill predator population, and I use archived backscatter data from an …
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Seasonal and Mesoscale Variability in the Distribution of Antarctic Krill, <i>Euphausia superba</i>, West of the Antarctic Peninsula
… variability in the distribution and abundance of Antarctic krill, Euphausia superba, within continental shelf waters west of the Antarctic Peninsula and to investigate possible relationships between variability in krill distributions and variability in selected environmental parameters. Acoustic …
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Multi-species models of Antarctic krill predators : do competitive effects influence estimates of pre-exploitation whale abundance and recovery?
Includes abstract. Includes bibliographical references (leaves 92-111).
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Circulation of the Western Antarctic Peninsula: Implications for Biological Production
<p>The western Antarctic Peninsula (wAP) continental shelf is characterized by large persistent populations of Antarctic krill (<em> Enphausia superba</em>) and by regions of enhanced concentrations of marine mammals and other predators (hot spots). This study focused on understanding the role of …
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Spatiotemporal variability in Antarctic krill (Euphausia superba) around South Georgia from Antarctic fur seal (Arctocephalus gazella) diets at two long term monitoring sites
… and economic importance, there is much about Antarctic krill (Euphausia superba Dana, 1852) that is still poorly understood. This is especially true for its recruitment into South Georgia’s waters, which is highly variable and difficult to predict. Krill fluctuations exert bottom-up pressures …
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Distribution, patchiness, and behavior of Antarctic zooplankton, assessed using multi-frequency acoustic techniques
… zooplankton distribution and patchiness in an antarctic continental shelf region were examined, with particular emphasis on the Antarctic krill, Euphausia superba. This was accomplished by the application of acoustic, video, and environmental sensors during surveys of the region in and around …
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Distributions of <i>Euphausia Superba</i>, <i>Euphausia Crystallorophias</i>, and <i>Pleuragramma Antarcticum</i> with Correlations to Environmental Variables in the Western Ross Sea, Antarctica
<p>Antarctic krill (<em>Euphausia superb</em>a), crystal krill (<em>Euphausia crystallorophias</em>), and Antarctic silverfish (<em>Pleuragramma antarcticum</em>) are key mid-trophic level species in the Ross Sea food web that provide connectivity between primary production and the upper trophic …
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Distribution, patchiness, and behavior of Antarctic zooplankton, assessed using multi-frequency acoustic techniques
… zooplankton distribution and patchiness in an antarctic continental shelf region were examined, with particular emphasis on the Antarctic krill, Euphausia superba. This was accomplished by the application of acoustic, video, and environmental sensors during surveys of the region in and around …
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Variability of zooplankton and sea surface temperature in the Southern Ocean
… of spatial patterns in the distribution of Antarctic krill (Euphausia superba) resulting from social behavior. Turbulence of the flow is found to provide favorable conditions for the evolution social behavior in an idealized biological-physical model. Second, I analyze observations of sea …
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Linked Changes in Prey Availability and Population Structure: Using Antarctic Fur Seals to Sample Marine Systems
… the foraging trip durations of lactating female Antarctic fur seals, to the abundance and availability of Antarctic krill, where the mean length of krill consumed is used a proxy of krill availability. Over six years, 1568 foraging trips were measured for 178 individual seals, foraging from Bird …
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Antarctic sea ice trends and its response to the Southern annular mode
… food web of the region, from phytoplankton to Antarctic krill through to the apex predators such as seals and penguins. Sea ice variability is determined by shifts in the atmospheric temperature distribution and shifts in the atmospheric circulation. The Southern Annular Mode (SAM) is the …
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Fine-Scale Foraging Behavior of Humpback Whales Megaptera novaeangliae in the Near-Shore Waters of the Western Antarctic Peninsula
… in the coastal waters of the Western Antarctic Peninsula during the austral autumn of 2009 and 2010. Discrete feeding events (i.e., lunges) were inferred from the biologging records of thirteen whales, including a mother and her calf. In general, humpback whales exhibited efficient …
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Acoustic classification of zooplankton
… applied to echoes from fluid-like zooplankton (Antarctic krill) to invert for angle of orientation using generic and animal-specific theoretical and empirical models. Application of these inversion techniques in situ will allow correct apportionment of backscattered energy to animal biomass, …
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Slope/shelf circulation and cross-slope/shelf transport out of a bay driven by eddies from the open ocean
Interaction between the Antarctic Circumpolar Current and the continental slope/shelf in the Marguerite Bay and west Antarctic Peninsula is examined as interaction between a wind-driven channel flow and a zonally uniform slope with a bay-shaped shelf to the south. Two control mechanisms, eddy …
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Assessment of early 20th Century climate model simulations of Antarctic Sea ice using historical commercial humpback whale catch data
… poleward during the austral summer to feed on Antarctic krill at a proximity to the ice edge. Humpback whale catch locations in the early 20th century corroborate with this foraging behaviour. Using humpback whale catch location data as a benchmark, the study aims to assess the skill of climate …
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A potential mechanism sustaining the biological hotspot around Palmer Deep Canyon
… is a submarine canyon located along the Western Antarctic Peninsula. The region is considered a biological hotspot due to the high number of marine predators during the austral summer. The mechanisms that drive this hotspot, however, are poorly understood. Glider and satellite-based temperature …
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Plasticity and partitioning of foraging behaviour among and within sympatric Pygocelis penguin populations
… seabird species - chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) penguins – differ among and within populations. I analysed high-resolution location (GPS) and dive data from 221 individuals breeding at two sites (Nelson Island and Kopaitic Island) in the West Antarctic Peninsula …