Beak colour dynamically signals changes in fasting status and parasite loads in king penguins

This research was funded by the French Polar Institute (IPEV–Research Program 119) and the French National Centre for Scientific Research (CNRS-INEE). Field logistic support was provided by Terres Australes et Antarctiques Françaises. Q.S. was funded by a doctoral fellowship from the Ministère Français de l’Education Supérieur et de la Recherche. We thank all over-wintering assistants: Benoit Gineste, Sylvia Pardonnet, Laureline Durand, Emilie Lefol and Hédi Saadaoui for field work and Emilio Rojas for helpful discussion on the analyses. We apologize to our stick insect (Carausius morosus) for bearing with VAV’s inquisitive curiosity during our debates on color ornaments in king penguins. We sincerely thank the editor and 2 anonymous reviewers for their helpful comments on a previous version of the paper.Peer reviewedPostprin

Peroxide grafted PDMS: hydrosilylation reaction study and thiol-ene chemistry as an alternative pathway

International audiencePeroxide containing PDMS were synthesized according to a new pathway. Although hydrosilylation is one of the main reaction carried out in silicone chemistry, the catalysts used are very sensitive to the chemical nature of the reactants and remained inefficient to graft allylic peroxide. Radical catalyzed thiol-ene chemistry was involved for the first time to yield an initiator group containing polymer. Peroxide grafted polysiloxane structure and decomposition were characterized using 1H, 13C and 29Si NMR, FT-IR and RAMAN spectroscopies, SEC and DSC. These macroinitiators can be used to obtain polysiloxane able to undergo cross-linking

The oxidative debt of fasting : evidence for short to medium-term costs of advanced fasting in adult king penguins

This research was funded by the French Polar Institute (IPEV–Research Program 119) and the French National Centre for Scientific Research (CNRS-INEE). We are especially grateful to Dominic L. Cram and one anonymous reviewer for helpful comments on the paper. Field logistic support was provided by Terres Australes et Antarctiques Françaises. QS was funded by a doctoral fellowship from the Ministère Français de l’Education Supérieur et de la Recherche.Peer reviewedPublisher PD

Behavioural Adjustment in Response to Increased Predation Risk: A Study in Three Duck Species

Predation directly triggers behavioural decisions designed to increase immediate survival. However, these behavioural modifications can have long term costs. There is therefore a trade-off between antipredator behaviours and other activities. This trade-off is generally considered between vigilance and only one other behaviour, thus neglecting potential compensations. In this study, we considered the effect of an increase in predation risk on the diurnal time-budget of three captive duck species during the wintering period. We artificially increased predation risk by disturbing two groups of 14 mallard and teals at different frequencies, and one group of 14 tufted ducks with a radio-controlled stressor. We recorded foraging, vigilance, preening and sleeping durations the week before, during and after disturbance sessions. Disturbed groups were compared to an undisturbed control group. We showed that in all three species, the increase in predation risk resulted in a decrease in foraging and preening and led to an increase in sleeping. It is worth noting that contrary to common observations, vigilance did not increase. However, ducks are known to be vigilant while sleeping. This complex behavioural adjustment therefore seems to be optimal as it may allow ducks to reduce their predation risk. Our results highlight the fact that it is necessary to encompass the whole individual time-budget when studying behavioural modifications under predation risk. Finally, we propose that studies of behavioural time-budget changes under predation risk should be included in the more general framework of the starvation-predation risk trade-off

Experimental stress during molt suggests the evolution of condition-dependent and condition-independent ornaments in the king penguin

Acknowledgments We thank Emilie Lefol for her help in the field, and two anonymous reviewers for their comments on the manuscript. This research was funded by the French Polar Institute (IPEV– Research Program 119) and the French National Centre for Scientific Research (CNRS- INEE). Field logistic support was provided by Terres Australes et Antarctiques Françaises. Q.S. was funded by a doctoral fellowship from the Ministère Français de l’Education Supérieur et de la Recherche.Peer reviewedPublisher PD

Oxidative stress and mitochondrial responses to stress exposure suggest that king penguins are naturally equipped to resist stress

We are grateful to four anonymous reviewers for their help in improving a previous draft of this manuscript and to the French Polar Institut (IPEV) for providing logistical support for this study through the programs 119 & 131. AS was self-funded during fieldwork, funded by the University of Angers during laboratory analyses, and was supported by a Marie Sklodowska-Curie Postdoctoral Fellowship (#658085) and a ‘Turku Collegium for Science and Medicine' Fellowship at the time of writing.Peer reviewedPublisher PD

Foster rather than biological parental telomere length predicts offspring survival and telomere length in king penguins

ACKNOWLEDGMENTS We are grateful to the field assistants who helped us with data collection in 2012-2013. This research was supported by the French Polar Research Institute (IPEV; program 119 ECONERGY), by the Centre National de la Recherche Scientifique (CNRS), by an International Emerging Action Grant (IEA n°203036) from the CNRS, and by the AXA Research Fund (post-doctoral fellowship to VA Viblanc). We are grateful to S Rogers and 5 anonymous reviewers for constructive and useful comments on previous drafts of the paper. DATA ACCESSIBILITY The data associated with this manuscript are available online at figshare doi: 10.6084/m9.figshare.12249902 (Viblanc et al. 2020).Peer reviewedPostprin

Road mortality of the algerian hedgehog (Atelerix algirus) in the Soummam valley (Algeria)

There are several reasons for mortality in a population of wild animals, but the most important in small animals is the mortality due to the road traffic. Because of the dense road network the hedgehog is in Western Europe one of the species most affected by road kills. In North-African countries and particularly in Algeria, both the road network and the number of cars have considerably increased in the last decades. Thus, the number of Algerian Hedgehogs (Atelerix algirus) victims of the traffic is high and regular. Along a road of ca 100 km with high traffic volume, localized in the Soummam valley (from Béjaia to Bouira), we recorded during 5 years (from 2002 to 2006) the number, places and dates of hedgehogs found killed. The road was surveyed from a car, three times a week, and the overall number of hedgehogs found killed was 459. The distribution of animals respective to their location showed a very high density in suburban areas with their diverse environmental structures such as forests, agricultural areas, hedges, and the woodlands around the wadi El Soummam tributaries. In the course of the year, the hedgehog road kills were maximal in spring and summer (42.92 and 34.64 % respectively), decreasing in autumn and reaching a minimum in winter (5.66 %). It was possible to determine the age and sex of 404 animals. Every year males were observed first in spring from March onwards. During this period more males than females were found dead (45.30 % and 31.19 % respectively). The strong locomotor activity of males in spring (maximum in May) and summer coincides with the period of reproduction. Additionally, their home range is larger than that of females. Juveniles were found mostly at the end of summer and the beginning of autumn (23.51 %). This period corresponds to dispersion and foraging for winter. At the end of autumn, the activity started to decrease and was further reduced in winter in order to save energy during the adverse times of the year. In this period it is likely that the animals reduce their metabolism and hibernate. These road kill data in Algerian hedgehogs reflect precisely the seasonal variations of locomotor activity, and physiological variations such as reproduction (in spring and summer) and hibernation (autumn, winter)Les causes de mortalité des populations d'animaux sauvages sont variées mais une des plus importantes chez les espèces de taille moyenne est due à la circulation routière. En Europe de l'Ouest, en relation avec l'existence d'un réseau routier dense, le Hérisson est une des espèces communes les plus touchées par le trafic routier. Dans les pays d'Afrique du Nord, et en particulier en Algérie, le parc automobile et les réseaux routiers se sont développés considérablement ces dernières décennies. Le Hérisson d'Algérie (Atelerix algirus) est une des principales espèces victimes du trafic routier dans la vallée de la Soummam (entre Béjaia et Bouira). Le long de cet axe routier d'environ 100 km à très fort trafic, nous avons pu relever pendant 5 ans (de 2002 à 2006) le nombre de hérissons trouvés morts. Les relevés effectués régulièrement, chaque semaine, ont permis de dénombrer 459 animaux écrasés. La répartition des animaux par localité a montré que le Hérisson est très fréquent à la périphérie des agglomérations présentant des milieux diversifiés: zones forestières, parcelles cultivées, haies, bocages bordés par les affluents de l'Oued El Soummam. Au cours de l'année, chez le Hérisson, la mortalité routière est maximale au printemps et en été (42,92 et 34,64 % respectivement), décroît en automne et est minimale en hiver (5,66 %). Chez 404 animaux, il a été possible de déterminer le sexe et l'âge. Ainsi, nous avons pu préciser que les mâles sont observés régulièrement les premiers, au printemps à partir de mars et que, pendant cette période, plus de mâles que de femelles sont trouvés morts (45,30 % et 31,19 % respectivement). Chez les mâles, cette forte activité locomotrice printanière (maximum en mai) et estivale est à relier à la période de reproduction et au fait que leur domaine vital est plus grand que celui des femelles. Les jeunes sont surtout trouvés en fin d'été et en début d'automne (23,51 %), période qui correspond à la dispersion et à la recherche de nourriture avant l'hiver. L'activité moindre en fin d'automne, puis réduite en hiver, est à relier aux conditions défavorables du milieu et à des stratégies de conservation d'énergie incluant des épisodes de vie ralentie. Ces résultats montrent des variations saisonnières nettes de l'activité locomotrice du Hérisson d'Algérie et reflètent des variations physiologiques précises comme la reproduction (au printemps et en été) et des épisodes de torpeur (en automne et en hiver)

How to measure mitochondrial function in birds using red blood cells : a case study in the king penguin and perspectives in ecology and evolution

We are grateful to the French Polar Institut (IPEV) for providing logistical support for this study through the programs 119 & 131, A. Bourguignon, Y. Handrich and A. Lewden for their contribution to the muscle biopsy sampling, V. Viblanc for his support through the IPEV program 119, and three anonymous reviewers for their help in improving the manuscript. A. Stier was supported by a Marie Sklodowska- Curie Postdoctoral Fellowship (#658085). Authors declare no conflict of interest.Peer reviewedPostprin

Foster rather than biological parental telomere length predicts offspring survival and telomere length in king penguins

Because telomere length and dynamics relate to individual growth, reproductive investment and survival, telomeres have emerged as possible markers of individual quality. Here, we tested the hypothesis that, in species with parental care, parental telomere length can be a marker of parental quality that predicts offspring phenotype and survival. In king penguins (Aptenodytes patagonicus), we experimentally swapped the single egg of 66 breeding pairs just after egg laying to disentangle the contribution of prelaying parental quality (e.g., genetics, investment in the egg) and/or postlaying parental quality (e.g., incubation, postnatal feeding rate) on offspring growth, telomere length and survival. Parental quality was estimated through the joint effects of biological and foster parent telomere length on offspring traits, both soon after hatching (day 10) and at the end of the prewinter growth period (day 105). We expected that offspring traits would be mostly related to the telomere lengths (i.e., quality) of biological parents at day 10 and to the telomere lengths of foster parents at day 105. Results show that chick survival up to 10 days was negatively related to biological fathers' telomere length, whereas survival up to 105 days was positively related to foster fathers' telomere lengths. Chick growth was not related to either biological or foster parents' telomere length. Chick telomere length was positively related to foster mothers' telomere length at both 10 and 105 days. Overall, our study shows that, in a species with biparental care, parents' telomere length is foremost a proxy of postlaying parental care quality, supporting the "telomere - parental quality hypothesis.