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Author Watanabe Yuuki Y, Takahashi Akinori, Sato Katsufumi, Viviant Morgane, Bost Charles-André,
Title Poor flight performance in deep-diving cormorants. Type Journal Article
Year 2011 Publication (down) The Journal of experimental biology Abbreviated Journal J. Exp. Biol.
Volume 214 Issue Pt 3 Pages 412 -21
Keywords Animals, Biomechanics, Birds, Birds: physiology, Body Weight, Diving, Diving: physiology, Energy Metabolism, Female, Flight, Animal, Flight, Animal: physiology, Male, Muscle, Skeletal, Muscle, Skeletal: physiology, Respiration, Seawater, Swimming, Swimming: physiology, Water, Wing, Wing: anatomy & histology, Wing: physiology,
Abstract Aerial flight and breath-hold diving present conflicting morphological and physiological demands, and hence diving seabirds capable of flight are expected to face evolutionary trade-offs regarding locomotory performances. We tested whether Kerguelen shags Phalacrocorax verrucosus, which are remarkable divers, have poor flight capability using newly developed tags that recorded their flight air speed (the first direct measurement for wild birds) with propeller sensors, flight duration, GPS position and depth during foraging trips. Flight air speed (mean 12.7 m s(-1)) was close to the speed that minimizes power requirement, rather than energy expenditure per distance, when existing aerodynamic models were applied. Flights were short (mean 92 s), with a mean summed duration of only 24 min day(-1). Shags sometimes stayed at the sea surface without diving between flights, even on the way back to the colony, and surface durations increased with the preceding flight durations; these observations suggest that shags rested after flights. Our results indicate that their flight performance is physiologically limited, presumably compromised by their great diving capability (max. depth 94 m, duration 306 s) through their morphological adaptations for diving, including large body mass (enabling a large oxygen store), small flight muscles (to allow for large leg muscles for underwater propulsion) and short wings (to decrease air volume in the feathers and hence buoyancy). The compromise between flight and diving, as well as the local bathymetry, shape the three-dimensional foraging range (<26 km horizontally, <94 m vertically) in this bottom-feeding cormorant.
Programme 394
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ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 2682
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Author Goutte Aurélie, Clément-Chastel Céline, Moe Børge, Bech Claus, Gabrielsen Geir Wing, Chastel Olivier,
Title Experimentally reduced corticosterone release promotes early breeding in black-legged kittiwakes Type Journal Article
Year 2011 Publication (down) The Journal of Experimental Biology Abbreviated Journal
Volume 214 Issue 12 Pages 2005 -2013
Keywords
Abstract Breeding at the right time is important for successful reproduction. In birds, stressful environmental conditions are known to delay the timing of breeding but the underlying mechanisms are poorly understood. The stress hormone corticosterone appears to be a good candidate for mediating egg-laying date according to early environmental conditions and physiological state. By experimentally reducing the release of corticosterone in black-legged kittiwakes during the pre-laying period, we tested whether egg-laying date was mechanistically linked to corticosterone levels. Male and female kittiwakes were implanted with a low dose of exogenous corticosterone to inhibit endogenous corticosterone production. According to our predictions, the experimental reduction of corticosterone release was paralleled by a significant advancement of egg laying in females (around 4 days earlier). In addition, females with experimentally reduced corticosterone release gained mass during the pre-laying period compared with controls. Ultimately, the advancement of egg laying in females with experimentally reduced corticosterone levels was associated with an enhanced breeding success. This effect was strongly sex specific. In corticosterone-treated male kittiwakes, egg-laying date and reproductive success were not affected, but breeding probability was lower than in controls. This corticosterone treatment did not influence immediate clutch size, or return rate and breeding decision the following year. Our results support the hypothesis that corticosterone secretion during the pre-laying period mediates the timing of breeding in this long-lived seabird, possibly through the dynamics of energy reserves.
Programme 330
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Corporate Author Thesis Bachelor's thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 3518
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Author Erbrech Aude, Robin Jean-Patrice, Guérin Nathalie, Groscolas René, Gilbert Caroline, Martrette Jean-Marc,
Title Differential muscular myosin heavy chain expression of the pectoral and pelvic girdles during early growth in the king penguin (Aptenodytes patagonicus) chick Type Journal Article
Year 2011 Publication (down) The Journal of Experimental Biology Abbreviated Journal J. Exp. Biol.
Volume 214 Issue 11 Pages 1829 -1835
Keywords
Abstract Continuous growth, associated with a steady parental food supply, is a general pattern in offspring development. So that young chicks can acquire their locomotor independence, this period is usually marked by a fast maturation of muscles, during which different myosin heavy chain (MyHC) isoforms are expressed. However, parental food provisioning may fluctuate seasonally, and offspring therefore face a challenge to ensure the necessary maturation of their tissues when energy is limited. To address this trade-off we investigated muscle maturation in both the pectoral and pelvic girdles of king penguin chicks. This species has an exceptionally long rearing period (1 year), which is prolonged when parental food provisioning is drastically reduced during the sub-Antarctic winter. Approximately 1 month post hatching, chicks acquire a functional pedestrian locomotion, which uses pelvic muscles, whereas swimming, which uses the pectoral muscles, only occurs 1 year later. We therefore tested the hypothesis that the MyHC content of the leg muscles reaches a mature state before those of the pectoral muscles. We found that leg muscle MyHC composition changed with the progressive acquisition of pedestrian locomotion, whereas pectoral muscle fibres reached their mature MyHC profile as early as hatching. Contrary to our predictions, the acquisition of the adult profile in pectoral muscles could be related to an early maturation of the contractile muscular proteins, presumably associated with early thermoregulatory capacities of chicks, necessary for survival in their cold environment. This differential maturation appears to reconcile both the locomotor and environmental constraints of king penguin chicks during growth.
Programme 119
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ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 3801
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Author Sachs G, Traugott J, Nesterova A P, Bonadonna F,
Title Experimental verification of dynamic soaring in albatrosses Type Journal Article
Year 2013 Publication (down) The Journal of Experimental Biology Abbreviated Journal
Volume 216 Issue 22 Pages 4222 -4232
Keywords
Abstract Dynamic soaring is a small-scale flight manoeuvre which is the basis for the extreme flight performance of albatrosses and other large seabirds to travel huge distances in sustained non-flapping flight. As experimental data with sufficient resolution of these small-scale movements are not available, knowledge is lacking about dynamic soaring and the physical mechanism of the energy gain of the bird from the wind. With new in-house developments of GPS logging units for recording raw phase observations and of a dedicated mathematical method for postprocessing these measurements, it was possible to determine the small-scale flight manoeuvre with the required high precision. Experimental results from tracking 16 wandering albatrosses (Diomedea exulans) in the southern Indian Ocean show the characteristic pattern of dynamic soaring. This pattern consists of four flight phases comprising a windward climb, an upper curve, a leeward descent and a lower curve, which are continually repeated. It is shown that the primary energy gain from the shear wind is attained in the upper curve where the bird changes the flight direction from windward to leeward. As a result, the upper curve is the characteristic flight phase of dynamic soaring for achieving the energy gain necessary for sustained non-flapping flight.
Programme 354
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 4740
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Author Monternier Pierre-Axel, Marmillot Vincent, Rouanet Jean-Louis, Roussel Damien,
Title Mitochondrial phenotypic flexibility enhances energy savings during winter fast in king penguin chicks Type Journal Article
Year 2014 Publication (down) The Journal of Experimental Biology Abbreviated Journal J. Exp. Biol.
Volume 217 Issue 15 Pages 2691 -2697
Keywords
Abstract Energy conservation is a key priority for organisms that live in environments with seasonal shortages in resource supplies or that spontaneously fast during their annual cycle. The aim of this study was to determine whether the high fasting endurance of winter-acclimatized king penguin chicks (Aptenodytes patagonicus) is associated with an adjustment of mitochondrial bioenergetics in pectoralis muscle, the largest skeletal muscle in penguins. The rates of mitochondrial oxygen consumption, and ATP synthesis and mitochondrial efficiency (ATP/O ratio) were measured in winter-acclimatized chicks. We used pyruvate/malate and palmitoyl-l-carnitine/malate as respiratory substrates and results from naturally fasted chicks were compared to experimentally re-fed chicks. Bioenergetics analysis of pectoralis muscle revealed that mitochondria are on average 15% more energy efficient in naturally fasted than in experimentally fed chicks, indicating that fasted birds consume less nutrients to sustain their energy-demanding processes. We also found that moderate reductions in temperature from 38°C to 30°C further increase by 23% the energy coupling efficiency at the level of mitochondria, suggesting that king penguin chicks realize additional energy savings while becoming hypothermic during winter. It has been calculated that this adjustment of mitochondrial efficiency in skeletal muscle may contribute to nearly 25% of fasting-induced reduction in mass-specific metabolic rate measured in vivo. The present study shows that the regulation of mitochondrial efficiency triggers the development of an economical management of resources, which would maximize the conservation of endogenous fuel stores by decreasing the cost of living in fasted winter-acclimatized king penguin chicks.
Programme 131
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ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 5179
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Author Richard Gaëtan, Vacquié-Garcia Jade, Jouma'a Joffrey, Picard Baptiste, Génin Alexandre, Arnould John P Y, Bailleul Frédéric, Guinet Christophe,
Title Variation in body condition during the post-moult foraging trip of southern elephant seals and its consequences on diving behaviour. Type Journal Article
Year 2014 Publication (down) The Journal of experimental biology Abbreviated Journal J. Exp. Biol.
Volume 217 Issue Pt 14 Pages 2609-19
Keywords Animals, Behavior, Animal, Behavior, Animal: physiology, Biomechanical Phenomena, Body Composition, Diving, Diving: physiology, Female, Oceans and Seas, Seals, Earless, Seals, Earless: physiology, Swimming, Swimming: physiology, Telemetry,
Abstract Mature female southern elephant seals (Mirounga leonina) come ashore only in October to breed and in January to moult, spending the rest of the year foraging at sea. Mature females may lose as much as 50% of their body mass, mostly in lipid stores, during the breeding season due to fasting and lactation. When departing to sea, post-breeding females are negatively buoyant, and the relative change in body condition (i.e. density) during the foraging trip has previously been assessed by monitoring the descent rate during drift dives. However, relatively few drift dives are performed, resulting in low resolution of the temporal reconstruction of body condition change. In this study, six post-breeding females were equipped with time-depth recorders and accelerometers to investigate whether changes in active swimming effort and speed could be used as an alternative method of monitoring density variations throughout the foraging trip. In addition, we assessed the consequences of density change on the swimming efforts of individuals while diving and investigated the effects on dive duration. Both descent swimming speed and ascent swimming effort were found to be strongly correlated to descent rate during drift dives, enabling the fine-scale monitoring of seal density change over the whole trip. Negatively buoyant seals minimized swimming effort during descents, gliding down at slower speeds, and reduced their ascent swimming effort to maintain a nearly constant swimming speed as their buoyancy increased. One per cent of seal density variation over time was found to induce a 20% variation in swimming effort during dives with direct consequences on dive duration.
Programme 109
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 5905
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Author Viblanc Vincent A, Smith Andrew D, Gineste Benoit, Kauffmann Marion, Groscolas René,
Title Modulation of heart rate response to acute stressors throughout the breeding season in the king penguin Aptenodytes patagonicus. Type Journal Article
Year 2015 Publication (down) The Journal of experimental biology Abbreviated Journal
Volume 218 Issue Pt 11 Pages 1686-92
Keywords
Abstract 'Fight-or-flight' stress responses allow animals to cope adaptively to sudden threats by mobilizing energy resources and priming the body for action. Because such responses can be costly and redirect behavior and energy from reproduction to survival, they are likely to be shaped by specific life-history stages, depending on the available energy resources and the commitment to reproduction. Here, we consider how heart rate (HR) responses to acute stressors are affected by the advancing breeding season in a colonial seabird, the king penguin (Aptenodytes patagonicus). We subjected 77 birds (44 males, 33 females) at various stages of incubation and chick-rearing to three experimental stressors (metal sound, distant approach and capture) known to vary both in their intensity and associated risk, and monitored their HR responses. Our results show that HR increase in response to acute stressors was progressively attenuated with the stage of breeding from incubation to chick-rearing. Stress responses did not vary according to nutritional status or seasonal timing (whether breeding was initiated early or late in the season), but were markedly lower during chick-rearing than during incubation. This pattern was obvious for all three stressors. We discuss how 'fight-or-flight' responses may be modulated by considering the energy commitment to breeding, nutritional status and reproductive value of the brood in breeding seabirds.
Programme 119
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Series Editor Series Title Abbreviated Series Title
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ISSN 0022-0949 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 6096
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Author Cunningham Gregory B, Bonadonna Francesco,
Title King penguins can detect two odours associated with conspecifics. Type Journal Article
Year 2015 Publication (down) The Journal of experimental biology Abbreviated Journal
Volume 218 Issue Pt 21 Pages 3374-6
Keywords
Abstract Recent studies on olfaction in penguins have focused on their use of odours while foraging. It has been proposed for some seabirds that an olfactory landscape shaped by odours coming from feeding areas exists. Islands and colonies, however, may also contribute to the olfactory landscape and may act as an orienting map. To test sensitivities to a colony scent we studied whether King penguins (Aptenodytes patagonicus) could detect the smell of sand, feathers or feces by holding presentations beneath their beaks while they naturally slept on the beach. Penguins had a significantly greater response to the feathers and feces presentations than to sand. Although only a first step in exploring a broader role of olfaction in this species, our results raise the possibility of olfaction being used by King penguins in three potential ways: (1) locating the colony from the water or the shore, (2) finding the rendezvous zone within the colony where a chick or partner may be found, or (3) recognizing individuals by scent, as in Humboldt penguins (Spheniscus demersus).
Programme 354
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Call Number Serial 6253
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Author Manfred R. Enstipp, Charles-André Bost, Céline Le Bohec, Nicolas Chatelain, Henri Weimerskirch, Yves Handrich
Title The early life of king penguins: ontogeny of dive capacity and foraging behaviour in an expert diver Type Journal
Year 2021 Publication (down) The Journal of Experimental Biology Abbreviated Journal
Volume 224 Issue 12 Pages jeb242512
Keywords Animals Behavior, Animal Bio-logging Diving Feeding Behavior Foraging proficiency Ontogeny Seabirds Spheniscidae Temperature Wiggles
Abstract The period of emancipation in seabirds, when juveniles change from a terrestrial existence to a life at sea, is associated with many challenges. Apart from finding favourable foraging sites, they have to develop effective prey search patterns and physiological capacities that enable them to capture sufficient prey to meet their energetic needs. Animals that dive to forage, such as king penguins (Aptenodytes patagonicus), need to acquire an adequate breath-hold capacity, allowing them to locate and capture prey at depth. To investigate the ontogeny of their dive capacity and foraging performance, we implanted juvenile king penguins before their first departure to sea and also adult breeders with a data-logger recording pressure and temperature. We found that juvenile king penguins possess a remarkable dive capacity when leaving their natal colony, enabling them to conduct dives in excess of 100 m within their first week at sea. Despite this, juvenile dive/foraging performance, investigated in relation to dive depth, remained below the adult level throughout their first year at sea, probably reflecting physiological limitations as a result of incomplete maturation. A significantly shallower foraging depth of juveniles, particularly during their first 5 months at sea, could also indicate differences in foraging strategy and targeted prey. The initially greater wiggle rate suggests that juveniles fed opportunistically and also targeted different prey from adults and/or that many of the wiggles of juveniles reflect unsuccessful prey-capture attempts, indicating a lower foraging proficiency. After 5 months, this difference disappeared, suggesting sufficient physical maturation and improvement of juvenile foraging skills.
Programme 137,394
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Corporate Author Thesis Bachelor's thesis
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ISSN 1477-9145 ISBN Medium
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Notes Approved yes
Call Number Serial 8473
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Author Berhanu, Tesfaye A. Meusinger, Carl Erbland, Joseph Jost, Rémy Bhattacharya, S. K. Johnson, Matthew S. Savarino, Joël
Title Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence Type Journal Article
Year 2014 Publication (down) The Journal of Chemical Physics Abbreviated Journal
Volume 140 Issue 244306 Pages
Keywords
Abstract Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. [“Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry,” J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate (15N, 17O, and 18O) provide ad- ditional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (δ15N, δ18O, and ô°€17O). From these measurements an average photolytic isotopic frac- tionation of 15ε = (-15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wave- lengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of 15ε = (-47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from -40 to -74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of 14NO3- and 15NO3- in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying this model under the experimental temperature as well as considering the shift in width and center well reproduced the values obtained in the laboratory study. These cross sections can be used in isotopic models to reproduce the stable isotopic composition of nitrate found in Antarctic snow profiles.
Programme 1011
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 4917
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