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Schmidt, A.; Alard, F.; Handrich, Y. (2006). Changes in body temperatures in king penguins at sea: the result of fine adjustments in peripheral heat loss? Am. J. Physiol. Regul. Integr. Comp. Physiol., 291(3), R608–618.
Abstract: To investigate thermoregulatory adjustments at sea, body temperatures (the pectoral muscle and the brood patch) and diving behavior were monitored during a foraging trip of several days at sea in six breeding king penguins Aptenodytes patagonicus. During inactive phases at sea (water temperature: 4-7{degrees}C), all tissues measured were maintained at normothermic temperatures. The brood patch temperature was maintained at the same values as those measured when brooding on shore (38{degrees}C). This high temperature difference causes a significant loss of heat. We hypothesize that high-energy expenditure associated with elevated peripheral temperature when resting at sea is the thermoregulatory cost that a postabsorptive penguin has to face for the restoration of its subcutaneous body fat. During diving, mean pectoral temperature was 37.6 {+/-} 1.6{degrees}C. While being almost normothermic on average, the temperature of the pectoral muscle was still significantly lower than during inactivity in five out of the six birds and underwent temperature drops of up to 5.5{degrees}C. Mean brood patch temperature was 29.6 {+/-} 2.5{degrees}C during diving, and temperature decreases of up to 21.6{degrees}C were recorded. Interestingly, we observed episodes of brood patch warming during the descent to depth, suggesting that, in some cases, king penguins may perform active thermolysis using the brood patch. It is hypothesized that functional pectoral temperature may be regulated through peripheral adjustments in blood perfusion. These two paradoxical features, i.e., lower temperature of deep tissues during activity and normothermic peripheral tissues while inactive, may highlight the key to the energetics of this diving endotherm while foraging at sea.
Programme: 394
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Fahlman, A.; Handrich, Y.; Woakes, A.J.; Bost, C.-A.; Holder, R.; Duchamp, C.; Butler, P.J. (2004). Effect of fasting on the VO2-fh relationship in king penguins, Aptenodytes patagonicus. Am. J. Physiol. Regul. Integr. Comp. Physiol., 287(4), R870–877.
Abstract: King penguins (Aptenodytes patagonicus) may fast for up to 30 days during their breeding period. As such extended fasting may affect the relationship between the rate of O2 consumption (O2) and heart rate (fH), five male king penguins were exercised at various speeds on repeated occasions during a fasting period of 24-31 days. In addition, O2 and fH were measured in the same animals during rest in cold air and water (4{degrees}C). O2 and fH at rest and O2 during exercise decreased with fasting. There was a significant relation between O2 and fH (r2 = 0.56) that was improved by including speed, body mass (Mb), number of days fasting (t), and a cross term between fH and t (r2 = 0.92). It was concluded that there was a significant change in the O2-fH relationship with fasting during exercise. As t is measurable in the field and was shown to be significant and, therefore, a practical covariate, a regression equation for use when birds are ashore was obtained by removing speed and Mb. When this equation was used, predicted O2 was in good agreement with the observed data, with an overall error of 3.0%. There was no change in the O2-fH relationship in penguins at rest in water.
Programme: 131;137;394
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Alexander, C. M. O., Maurette, M., Swan, P., & Walker, R. M. (1992). Studies of Antarctic micrometeorites. Abstracts of the Lunar and Planetary Science Conference, 23, 7.
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Gasparini, J., Roulin, A., Gill, V., Hatch, S.A. & Boulinier, T. (2006). In kittiwakes food availability partially explains the seasonal decline in humoral immunocompetence. Functional ecology, 20, 457–463.
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Gasparini, J., McCoy, K.D., Staszewski, V., Haussy, C. & Boulinier, T. (2006). Dynamics of anti-Borrelia antibodies in kittiwake chicks (Rissa tridactyla) suggests a maternal educational effect. Can. J. Zool., 84, 623–627.
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Boulinier, T., Betoulle, S., Caza, F., St Pierre, Y., Tornos, J., Gamble, A. &Amp; Tasiemski, A. (2020). Bachelor's thesis, , .
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Viblanc Va, Stier A, Bize P, Schull Q, Criscuolo F, Groscolas R, Robin Jp. (2021). The ecophysiology of king penguins : responses to a fluctuating environment. Bachelor's thesis, , .
Abstract: Penguins are sea...birds. These highly evolved marine predators thrive in the oceanic habitat. Yet, they are conflicted – confronted to the duality of a life spent partly at sea, partly on-land. This life style has them subject to a number of very different ecological pressures. The ECONERGY polar project (IPEV #119) seeks to understand how king penguin cope with the constraints they face while living on-land, and the underlying physiological adaptations that allow them to do so. This includes studies dealing with fasting, parasites, predators, aggressive neighbors, climate and human disturbance. I will present some of the advances our project has made over the past decades, and where we will proceed in the years to come with a new project. We aim to understand bird stress from an integrative perspective, building a long-term observatory of penguin physiological responses to a changing world, and determining how breeding performances on land and foraging performances at sea are related.
Programme: 119
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. (2019). (Vol. 13). Bachelor's thesis, , .
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. (2020). Ground-based validation of the Copernicus Sentinel-5p TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networks. Bachelor's thesis, , .
Abstract: This Paper Reports On Consolidated Ground-based Validation Results Of The Atmospheric No2 Data Produced Operationally Since April 2018 By The Tropomi Instrument On Board Of The Esa/eu Copernicus Sentinel-5 Precursor (S5p) Satellite. Tropospheric, Stratospheric, And Total No2 Column Data From S5p Are Compared To Correlative Measurements Collected From, Respectively, 19 Multi-axis Doas (Max-doas), 26 Ndacc Zenith-scattered-light Doas (Zsl-doas), And 25 Pgn/pandora Instruments Distributed Globally. The Validation Methodology Gives Special Care To Minimizing Mismatch Errors Due To Imperfect Spatio-temporal Co-location Of The Satellite And Correlative Data, E.g., By Using Tailored Observation Operators To Account For Differences In Smoothing And In Sampling Of Atmospheric Structures And Variability, And Photochemical Modelling To Reduce Diurnal Cycle Effects. Compared To The Ground-based Measurements, S5p Data Show, On An Average: (I) A Negative Bias For The Tropospheric Column Data, Of Typically ?23 To ?37?% In Clean To Slightly Polluted Conditions, But Reaching Values As High As ?51?% Over Highly Polluted Areas; (Ii) A Slight Negative Bias For The Stratospheric Column Data, Of About ?0.2?Pmolec/cm2, I.e. Approx. ?2?% In Summer To ?15?% In Winter; And (Iii) A Bias Ranging From Zero To ?50?% For The Total Column Data, Found To Depend On The Amplitude Of The Total No2 Column, With Small To Slightly Positive Bias Values For Columns Below 6?Pmolec/cm2 And Negative Values Above. The Dispersion Between S5p And Correlative Measurements Contains Mostly Random Components, Which Remain Within Mission Requirements For The Stratospheric Column Data (0.5?Pmolec/cm2), But Exceed Those For The Tropospheric Column Data (0.7?Pmolec/cm2). While A Part Of The Biases And Dispersion May Be Due To Representativeness Differences, It Is Known That Errors In The S5p Tropospheric Columns Exist Due To Shortcomings In The (Horizontally Coarse) A-priori Profile Representation In The Tm5-mp Chemistry Transport Model Used In The S5p Retrieval, And To A Lesser Extent, To The Treatment Of Cloud Effects. Although Considerable Differences (Up To 2?Pmolec/cm2 And More) Are Observed At Single Ground-pixel Level, The Near-real-time (Nrti) And Off-line (Offl) Versions Of The S5p No2 Operational Data Processor Provide Similar No2 Column Values And Validation Results When Globally Averaged, With The Nrti Values Being On Average 0.79?% Larger Than The Offl Values.
Programme: 209
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. (2020). (Vol. 20). Bachelor's thesis, , .
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