. (2011). It Costs to Be Clean and Fit: Energetics of Comfort Behavior in Breeding-Fasting Penguins
. 1932-6203, 6(7), e21110–.
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. (2011). Effects of Individual Pre-Fledging Traits and Environmental Conditions on Return Patterns in Juvenile King Penguins
. PLoS ONE, 6(6), e20407–.
Abstract: Despite the importance of early life stages in individuals' life history and population dynamics, very few studies have focused on the constraints to which these juvenile traits are subjected. Based on 10 years of automatic monitoring of over 2500 individuals, we present the first study on the effects of environmental conditions and individual pre-fledging traits on the post-fledging return of non-banded king penguins to their natal colony. Juvenile king penguins returned exclusively within one of the three austral summers following their departure. A key finding is that return rates (range 68-87%) were much higher than previously assumed for this species, importantly meaning that juvenile survival is very close to that of adults. Such high figures suggest little juvenile dispersal, and selection occurring mostly prior to fledging in king penguins. Pre-fledging conditions had a strong quadratic impact on juvenile return rates. As expected, cohorts reared under very unfavourable years (as inferred by the breeding success of the colony) exhibited low return rates but surprisingly, so did those fledged under very favourable conditions. Juvenile sojourns away from the colony were shorter under warm conditions and subsequent return rates higher, suggesting a positive effect of climate warming. The longer the post-fledging trip (1, 2 or 3 years), the earlier in the summer birds returned to their natal colony and the longer they stayed before leaving for the winter journey. The presence of juveniles in the colony was more than twice the duration required for moulting purposes, yet none attempted breeding in the year of their first return. Juvenile presence in the colony may be important for acquiring knowledge on the social and physical colonial environment and may play an important part in the learning process of mating behaviour. Further studies are required to investigate its potential implications on other life-history traits such as recruitment age.
Programme: 137
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Jaeger Audrey, Cherel Yves, . (2011). Isotopic Investigation of Contemporary and Historic Changes in Penguin Trophic Niches and Carrying Capacity of the Southern Indian Ocean
. PLoS ONE, 6(2), e16484–.
Abstract: A temperature-defined regime shift occurred in the 1970s in the southern Indian Ocean, with simultaneous severe decreases in many predator populations. We tested a possible biological link between the regime shift and predator declines by measuring historic and contemporary feather isotopic signatures of seven penguin species with contrasted foraging strategies and inhabiting a large latitudinal range. We first showed that contemporary penguin isotopic variations and chlorophyll a concentration were positively correlated, suggesting the usefulness of predator δ13C values to track temporal changes in the ecosystem carrying capacity and its associated coupling to consumers. Having controlled for the Suess effect and for increase CO2 in seawater, δ13C values of Antarctic penguins and of king penguins did not change over time, while δ13C of other subantarctic and subtropical species were lower in the 1970s. The data therefore suggest a decrease in ecosystem carrying capacity of the southern Indian Ocean during the temperature regime-shift in subtropical and subantarctic waters but not in the vicinity of the Polar Front and in southward high-Antarctic waters. The resulting lower secondary productivity could be the main driving force explaining the decline of subtropical and subantarctic (but not Antarctic) penguins that occurred in the 1970s. Feather δ15N values did not show a consistent temporal trend among species, suggesting no major change in penguins’ diet. This study highlights the usefulness of developing long-term tissue sampling and data bases on isotopic signature of key marine organisms to track potential changes in their isotopic niches and in the carrying capacity of the environment.
Programme: 109
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Clark Melody S, Thorne Michael A S, Toullec Jean-Yves, Meng Yan, Guan Le Luo, Peck Lloyd S, Moore Stephen, . (2011). Antarctic krill 454 pyrosequencing reveals chaperone and stress transcriptome.
. PloS one, 6(1), e15919.
Abstract: The Antarctic krill Euphausia superba is a keystone species in the Antarctic food chain. Not only is it a significant grazer of phytoplankton, but it is also a major food item for charismatic megafauna such as whales and seals and an important Southern Ocean fisheries crop. Ecological data suggest that this species is being affected by climate change and this will have considerable consequences for the balance of the Southern Ocean ecosystem. Hence, understanding how this organism functions is a priority area and will provide fundamental data for life history studies, energy budget calculations and food web models.
Programme: 1039
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Raymond Ben, Shaffer Scott A, Sokolov Serguei, Woehler Eric J, Costa Daniel P, Einoder Luke, Hindell Mark, Hosie Graham, Pinkerton Matt, Sagar Paul M, Scott Darren, Smith Adam, Thompson David R, Vertigan Caitlin, Weimerskirch Henri, . (2010). Shearwater foraging in the Southern Ocean: the roles of prey availability and winds.
. PloS one, 5(6), e10960.
Abstract: BACKGROUND: Sooty (Puffinus griseus) and short-tailed (P. tenuirostris) shearwaters are abundant seabirds that range widely across global oceans. Understanding the foraging ecology of these species in the Southern Ocean is important for monitoring and ecosystem conservation and management. METHODOLOGY/PRINCIPAL FINDINGS: Tracking data from sooty and short-tailed shearwaters from three regions of New Zealand and Australia were combined with at-sea observations of shearwaters in the Southern Ocean, physical oceanography, near-surface copepod distributions, pelagic trawl data, and synoptic near-surface winds. Shearwaters from all three regions foraged in the Polar Front zone, and showed particular overlap in the region around 140 degrees E. Short-tailed shearwaters from South Australia also foraged in Antarctic waters south of the Polar Front. The spatial distribution of shearwater foraging effort in the Polar Front zone was matched by patterns in large-scale upwelling, primary production, and abundances of copepods and myctophid fish. Oceanic winds were found to be broad determinants of foraging distribution, and of the flight paths taken by the birds on long foraging trips to Antarctic waters. CONCLUSIONS/SIGNIFICANCE: The shearwaters displayed foraging site fidelity and overlap of foraging habitat between species and populations that may enhance their utility as indicators of Southern Ocean ecosystems. The results highlight the importance of upwellings due to interactions of the Antarctic Circumpolar Current with large-scale bottom topography, and the corresponding localised increases in the productivity of the Polar Front ecosystem.
Keywords: Animals, Biodiversity, Birds, Birds: physiology, Ecology, Marine Biology, Oceans and Seas, Predatory Behavior, Wind,
Programme: 109
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. (2010). Buoyancy under Control: Underwater Locomotor Performance in a Deep Diving Seabird Suggests Respiratory Strategies for Reducing Foraging Effort
. PLoS ONE, 5(3), e9839–.
Abstract: Background
Because they have air stored in many body compartments, diving seabirds are expected to exhibit efficient behavioural strategies for reducing costs related to buoyancy control. We study the underwater locomotor activity of a deep-diving species from the Cormorant family (Kerguelen shag) and report locomotor adjustments to the change of buoyancy with depth.
Methodology/Principal Findings
Using accelerometers, we show that during both the descent and ascent phases of dives, shags modelled their acceleration and stroking activity on the natural variation of buoyancy with depth. For example, during the descent phase, birds increased swim speed with depth. But in parallel, and with a decay constant similar to the one in the equation explaining the decrease of buoyancy with depth, they decreased foot-stroke frequency exponentially, a behaviour that enables birds to reduce oxygen consumption. During ascent, birds also reduced locomotor cost by ascending passively. We considered the depth at which they started gliding as a proxy to their depth of neutral buoyancy. This depth increased with maximum dive depth. As an explanation for this, we propose that shags adjust their buoyancy to depth by varying the amount of respiratory air they dive with.
Conclusions/Significance
Calculations based on known values of stored body oxygen volumes and on deep-diving metabolic rates in avian divers suggest that the variations of volume of respiratory oxygen associated with a respiration mediated buoyancy control only influence aerobic dive duration moderately. Therefore, we propose that an advantage in cormorants – as in other families of diving seabirds – of respiratory air volume adjustment upon diving could be related less to increasing time of submergence, through an increased volume of body oxygen stores, than to reducing the locomotor costs of buoyancy control.
Programme: 394
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. (2017). Antarctica and the strategic plan for biodiversity (Vol. 15).
Keywords: Antarctic Ocean Antarctica Biodiversity Conservation science Invasive species Marine conservation Marine ecology Marine ecosystems
Programme: 137
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Eduardo Dopico & Eva Garcia-Vazquez. (2016). Outreach channels for polar science: an expedition to Kerguelen Islands as a case study. Advances in polar science, , 31–38.
Abstract: This paper reviews the major contributions made by Norwegian scientists to Arctic environmental sciences since the 1880s.The review begins with the first International Polar Year (IPY) in 1882-83. It then considers the 1890s to 1920s with the scientific expeditions focusing on ocean and sea ice conditions of Nansen, Amundsen and H. Sverdrup, and the mapping of the Queen Elizabeth Islands by Otto Sverdrup and colleagues. The period from 1911 to the mid-1920s also witnessed annual expeditions to Svalbard led by Adolf Hoel. The 1930s to 1945 period encompassed the Second International Polar Year when Arctic weather stations were established or maintained. The time interval post-World War II to 2000 witnessed major advancesmade possible by technical and organizational innovations. The establishment of the Norwegian Polar Institute in 1948 led to extensive research on the glaciers and snow cover in the Svalbard archipelago and to oceanographic and sea ice research in the Barents Sea and Arctic Ocean. Remote sensing methods began to be widely used from the 1980s. The new millennium saw theundertaking of the third IPY and a shift to multinational projects. New fields such as ocean–ice–atmosphere variability became active and there was much attention to high-latitude climate change in the context of global warming.
Programme: 1041
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. (2022). Autonomous Optical Sensor to Study the Evolution of Snow Density in Polar Environment (Vol. Proceedings of Imaging and Applied Optics Congress).
Abstract: A system to study the evolution of snow density is presented here with an emphasis on the system itself and on the efforts to make a robust system for harsh environments. The metric to deduce the density of the snow is the measurement of the concentration of ambient air oxygen using a tunable diode laser spectroscopy technique: the first harmonic phase angle wavelength modulation spectroscopy. For greater robustness, the system is equipped with an embedded calibration system and is built for a smart power consumption.
Programme: 1042
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Ropert-coudert Y, Kato A, Robbins A, Humphries Grw . (2018). The Penguiness dive record data table. Explorable at http://www.penguiness.net.
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