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Author |
Hannah Joy Kriesell, Thierry Aubin, Víctor Planas-Bielsa, Quentin Schull, Francesco Bonadonna, Clément Cornec, Yvon Le Maho, Laura Troudet, Céline Le Bohec |
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Title |
How king penguins advertise their sexual maturity |
Type |
Journal |
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Year |
2021 |
Publication |
Animal Behaviour |
Abbreviated Journal |
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Volume |
177 |
Issue |
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Pages |
253-267 |
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Keywords |
animal communication mate choice optimal response index ornamentation penguin sexual maturation vocalization |
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Abstract |
Reproductive success can improve with experience, which increases with age in many long-lived species. Signals that provide reliable information about age are therefore of importance for mate choice and consequently are under sexual selection. In birds, these are often vocal signals as well as visual signals in the form of plumage coloration. King penguins, Aptenodytes patagonicus, are sexually monomorphically ornamented seabirds that perform a complex visual and acoustic courtship display. Coloured beak spots and ear patches contain information about the condition and physiological status of adult males and females, but their role as a signal of age has previously only been studied in young birds. Vocalizations have mainly been studied as signals of individuality and not in the context of courtship. We investigated two multicomponent signals in the context of mate choice by analysing beak spot, ear patch and call parameters of wild king penguins. We explored the relation between these signals and age as well as age classes (chicks, juveniles, adults). Ornament parameters were weakly correlated with in males, but not in females, while acoustic parameters were highly correlated with age in both sexes. The calls' fundamental frequency and energy parameters and all the beak spot parameters reliably classified individuals into their age class. Since age class was redundantly encoded in both acoustic and colour parameters, we hypothesize that calls and ornaments function as back-up signals that increase the chance of accurately conveying the age class of the sender to receivers. King penguins might sequentially analyse age class signals during courtship, where acoustic signals serve as long-range communication when sender and receiver are out of sight, and ornamentation signals become important at close range. We show the importance of considering bimodal, multicomponent signals when studying complex behaviour and discuss how signalling environment, the species’ life history and mating system influence the evolution of communication signals. |
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137,354 |
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Bachelor's thesis |
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0003-3472 |
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yes |
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Serial |
7949 |
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Author |
Mulard, H., Aubin, T., White, J. F., Hatch, S. A. and Danchin, É. |
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Title |
Experimental evidence of vocal recognition in young and adult black-legged kittiwakes |
Type |
Journal Article |
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Year |
2008 |
Publication |
Animal behaviour |
Abbreviated Journal |
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Volume |
76 |
Issue |
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Pages |
1855-1861 |
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1162 |
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0003-3472 |
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yes |
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Call Number |
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Serial |
5283 |
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Author |
Le Bohec C., Gauthier-Clerc M. & Le Maho Y. |
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Title |
The adaptive significance of crèches in the king penguin. |
Type |
Journal Article |
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Year |
2005 |
Publication |
Animal behaviour |
Abbreviated Journal |
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Volume |
70 |
Issue |
3 |
Pages |
527-538 |
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Abstract |
Crèching behaviour in penguins is defined as the rearing of chicks by their own parents in large flocks called 'crèches'. Although several hypotheses have been proposed to account for the behaviour, the factors inducing chicks to aggregate remain relatively poorly understood, in particular for colonial seabirds. We studied crèching behaviour in the king penguin, Aptenodytes patagonicus, by looking at the dynamics of crèche formation and possible costs and benefits associated with this strategy. Crèches increased in size but declined in number throughout the austral winter. They were located preferentially in the central parts of the colony. Lone chicks suffered the most aggression from unrelated adults, whereas chicks in a crèche suffered the least. Chicks attacked by unrelated adults preferentially joined a crèche. Adult aggression appeared to be a major factor inducing crèching behaviour. Chicks at the periphery of a crèche were more vigilant while sleeping, as measured by eye openings. Crèches seemed to occasion intense competition among chicks for access to the centre. Chicks in poor condition were attacked and pushed to the periphery of the crèche, where they were preyed on by giant petrels. During harsh weather conditions, chicks amalgamated into larger crèches, tolerated lower interindividual distances and turned their backs to the wind and rain. Our results accord with the idea that crèching behaviour in king penguins is a strategy that protects chicks from adult aggression, predation and severe weather. |
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137 |
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0003-3472 |
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yes |
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Serial |
2901 |
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Author |
Bonadonna F., Villafane M., Bajzak C. & Jouventin P. |
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Title |
Recognition of burrow’s olfactory signature in blue petrels, Halobaena caerulea: an efficient discrimination mechanism in the dark |
Type |
Journal Article |
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Year |
2004 |
Publication |
Animal behaviour |
Abbreviated Journal |
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Volume |
67 |
Issue |
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Pages |
893-898 |
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Keywords |
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Abstract |
Previous work has shown that blue petrels need olfaction to home. We investigated whether they also recognize an olfactory signature of their own nest. We performed T-maze experiments in which maze arms were connected with the subject bird’s burrow and with the burrow of a conspecific neighbour. Of 23 birds, 16 were able to recognize the arm leading to their own burrow. In a second experiment, we positioned the maze in front of the subject’s burrow but the maze arms were closed and did not enter the burrow. Consequently, no burrow odours could be sensed by the bird. In this case, 85% of birds (17 of 20) failed to choose, suggesting that petrels were not motivated to choose by positional cues in the absence of odour
cues. We explored this idea further by performing a homing experiment whereby homing birds had to relocate an artificially displaced burrow entrance. Blue petrels homed, ignoring the natural burrow entrance and using the new artificial one. The ability to smell their own burrow allows blue petrels to return to the colony at night and to find the correct nest. |
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Programme |
354 |
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Bachelor's thesis |
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ISSN |
0003-3472 |
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Approved |
yes |
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Call Number |
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Serial |
2601 |
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Author |
Junaid S. Khan, Jennifer F. Provencher, Mark R. Forbes, Mark L. Mallory, Camille Lebarbenchon, Karen D. McCoy |
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Title |
Chapter One – Parasites of seabirds: A survey of effects and ecological implications |
Type |
Journal |
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Year |
2019 |
Publication |
Advances in Marine Biology |
Abbreviated Journal |
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Volume |
82 |
Issue |
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Pages |
1-50 |
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Keywords |
Animals Bacteria Bird Birds Ectoparasite Endoparasite Helminth Host-Parasite Interactions Marine Oceans and Seas Parasitism Pathogen Research Seabird Virus |
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Abstract |
Parasites are ubiquitous in the environment, and can cause negative effects in their host species. Importantly, seabirds can be long-lived and cross multiple continents within a single annual cycle, thus their exposure to parasites may be greater than other taxa. With changing climatic conditions expected to influence parasite distribution and abundance, understanding current level of infection, transmission pathways and population-level impacts are integral aspects for predicting ecosystem changes, and how climate change will affect seabird species. In particular, a range of micro- and macro-parasites can affect seabird species, including ticks, mites, helminths, viruses and bacteria in gulls, terns, skimmers, skuas, auks and selected phalaropes (Charadriiformes), tropicbirds (Phaethontiformes), penguins (Sphenisciformes), tubenoses (Procellariiformes), cormorants, frigatebirds, boobies, gannets (Suliformes), and pelicans (Pelecaniformes) and marine seaducks and loons (Anseriformes and Gaviiformes). We found that the seabird orders of Charadriiformes and Procellariiformes were most represented in the parasite-seabird literature. While negative effects were reported in seabirds associated with all the parasite groups, most effects have been studied in adults with less information known about how parasites may affect chicks and fledglings. We found studies most often reported on negative effects in seabird hosts during the breeding season, although this is also the time when most seabird research occurs. Many studies report that external factors such as condition of the host, pollution, and environmental conditions can influence the effects of parasites, thus cumulative effects likely play a large role in how parasites influence seabirds at both the individual and population level. With an increased understanding of parasite-host dynamics it is clear that major environmental changes, often those associated with human activities, can directly or indirectly affect the distribution, abundance, or virulence of parasites and pathogens. |
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Programme |
333 |
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Thesis |
Bachelor's thesis |
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ISSN |
2162-5875 |
ISBN |
2162-5875 |
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Approved |
yes |
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Call Number |
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Serial |
7531 |
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Author |
Vincent Favier, Gerhard Krinner, Charles Amory, Hubert Gallée, Julien Beaumet, Cécile Agosta |
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Title |
Antarctica-Regional Climate and Surface Mass Budget |
Type |
Book Chapter |
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Year |
2017 |
Publication |
Current Climate Change Reports |
Abbreviated Journal |
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Volume |
3 |
Issue |
4 |
Pages |
303-315 |
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Keywords |
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Abstract |
We review recent literature on atmospheric, surface ocean and sea-ice observations and modeling results in the Antarctic sector and relate the observed climatic trends with the potential changes in the surface mass balance (SMB) of the ice sheet since 1900. Estimates of regional scale SMB distribution and trends remain subject to large uncertainties. Approaches combining and comparing multiple satellite and model-based assessments of ice sheet mass balance aim at reducing these knowledge gaps. During the last decades, significant changes in atmospheric circulation occurred around Antarctica, due to the exceptional positive trend in the Southern Annular Mode and to the climate variability observed in the tropical Pacific at the end of the twentieth century. Even though climate over the East Antarctic Ice-Sheet remained quite stable, a warming and precipitation increase was observed over the West Antarctic Ice-Sheet and over the West Antarctic Peninsula (AP) during the twentieth century. However, the high regional climate variability overwhelms climate changes associated to human drivers of global temperature changes, as reflected by a slight recent decadal cooling trend over the AP. Climate models still fail to accurately reproduce the multi-decadal SMB trends at a regional scale, and progress has to be achieved in reproducing atmospheric circulation changes related to complex ocean/ice/atmosphere interactions. Complex processes are also still insufficiently considered, such as (1) specific polar atmospheric processes (clouds, drifting snow, and stable boundary layer physics), (2) surface firn physics involved in the surface drag variations, or in firn air depletion and albedo feedbacks. Finally, progress in reducing the uncertainties relative to projections of the future SMB of Antarctica will largely depend on climate model capability to correctly consider teleconnections with low and mid-latitudes, and on the ability to correct them for biases, taking into account the coupling between ocean, ice, and atmosphere in high southern latitudes. |
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Programme |
411,1154 |
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Bachelor's thesis |
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ISSN |
2198-6061 |
ISBN |
2198-6061 |
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yes |
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Call Number |
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Serial |
6735 |
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Author |
Falk Huettmann, Yuri Artukhin, Olivier Gilg, Grant Humphries |
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Title |
Predictions of 27 Arctic pelagic seabird distributions using public environmental variables, assessed with colony data: a first digital IPY and GBIF open access synthesis platform |
Type |
Journal |
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Year |
2011 |
Publication |
Marine Biodiversity |
Abbreviated Journal |
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Volume |
41 |
Issue |
1 |
Pages |
141-179 |
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Keywords |
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Abstract |
We present a first compilation, quantification and summary of 27 seabird species presence data for north of the Arctic circle (>66 degrees latitude North) and the ice-free period (summer). For species names, we use several taxonomically valid online databases [Integrated Taxonomic Information System (ITIS), AviBase, 4 letter species codes of the American Ornithological Union (AOU), The British List 2000, taxonomic serial numbers TSNs, World Register of Marine Species (WORMS) and APHIA ID] allowing for a compatible taxonomic species cross-walk, and subsequent applications, e.g., phylogenies. Based on the data mining and machine learning RandomForest algorithm, and 26 environmental publicly available Geographic Information Systems (GIS) layers, we built 27 predictive seabird models based on public open access data archives such as the Global Biodiversity Information Facility (GBIF), North Pacific Pelagic Seabird Database (NPPSD) and PIROP database (in OBIS-Seamap). Model-prediction scenarios using pseudo-absence and expert-derived absence were run; aspatial and spatial model assessment metrics were applied. Further, we used an additional species model performance metric based on the best publicly available Arctic seabird colony location datasets compiled by the authors using digital and literature sources. The obtained models perform reasonably: from poor (only a few coastal species with low samples) to very high (many pelagic species). In compliance with data policies of the International Polar Year (IPY) and similar initiatives, data and models are documented with FGDC NBII metadata and publicly available online for further improvement, sustainability applications, synergy, and intellectual explorations in times of a global biodiversity, ocean and Arctic crisis. |
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Programme |
1036 |
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Bachelor's thesis |
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ISSN |
1867-1616, 1867-1624 |
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yes |
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Serial |
6987 |
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Author |
Villante, U.; De Lauretis, M.; Francia, P.; Vellante, M.; Piancatelli, A. |
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Title |
Experimental Aspects of Mid-Frequency Pulsations ( f ?10–100 mHz) in the Southern Polar Cap |
Type |
Journal Article |
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Year |
2006 |
Publication |
Space science reviews |
Abbreviated Journal |
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Volume |
122 |
Issue |
1 |
Pages |
107-117 |
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Abstract |
Abstract We review the results obtained in the frequency range of Pc3 (22-100 mHz) and Pc4 (7-22 mHz) pulsations at Italian Antarctic stations in the southern polar cap (“Mario Zucchelli”, at Terra Nova Bay, TNB, 80?.S; “Concordia”, the Italian/French base at Dome C, DMC, 89?.S). The absence of a midnight enhancement in the pulsation power suggests a negligible substorm influence at extreme latitudes, while the sharp noon enhancement, which appears only at TNB, is determined by the closer proximity of the station to cusp related phenomena. The relationship between the frequency of the band-limited signals and the interplanetary magnetic field strength, the cone angle influence, and the higher correlation of the Pc3 power with the solar wind speed in the morning hours suggest a global scenario in which upstream waves would be mainly responsible for the mid-frequency activity in the polar cap. However, the polarization pattern is odd with respect to the predictions for tailward propagating modes. |
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1130 |
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0038-6308 |
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yes |
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Call Number |
IPEV @ Thierry.Lemaire @ |
Serial |
5531 |
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Author |
K. Bocchialini, B. Grison, M. Menvielle, A. Chambodut, N. Cornilleau-Wehrlin, D. Fontaine, A. Marchaudon, M. Pick, F. Pitout, B. Schmieder, S. Régnier, I. Zouganelis |
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Title |
Statistical Analysis of Solar Events Associated with Storm Sudden Commencements over One Year of Solar Maximum During Cycle 23: Propagation from the Sun to the Earth and Effects |
Type |
Book Chapter |
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Year |
2017 |
Publication |
Solar Physics |
Abbreviated Journal |
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Volume |
293 |
Issue |
5 |
Pages |
75 |
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Keywords |
Earth: SSC geoeffectiveness Solar wind: ICME Sun: CME |
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Abstract |
Taking the 32 storm sudden commencements (SSCs) listed by the International Service of Geomagnetic Indices (ISGI) of the Observatory de l’Ebre during 2002 (solar activity maximum in Cycle 23) as a starting point, we performed a multi-criterion analysis based on observations (propagation time, velocity comparisons, sense of the magnetic field rotation, radio waves) to associate them with solar sources, identified their effects in the interplanetary medium, and looked at the response of the terrestrial ionized and neutral environment. We find that 28 SSCs can be related to 44 coronal mass ejections (CMEs), 15 with a unique CME and 13 with a series of multiple CMEs, among which 19 (68%) involved halo CMEs. Twelve of the 19 fastest CMEs with speeds greater than 1000 km s−1 are halo CMEs. For the 44 CMEs, including 21 halo CMEs, the corresponding X-ray flare classes are: 3 X-class, 19 M-class, and 22 C-class flares. The probability for an SSC to occur is 75% if the CME is a halo CME. Among the 500, or even more, front-side, non-halo CMEs recorded in 2002, only 23 could be the source of an SSC, i.e. 5%. The complex interactions between two (or more) CMEs and the modification of their trajectories have been examined using joint white-light and multiple-wavelength radio observations. The detection of long-lasting type IV bursts observed at metric–hectometric wavelengths is a very useful criterion for the CME–SSC events association. The events associated with the most depressed Dst values are also associated with type IV radio bursts. The four SSCs associated with a single shock at L1 correspond to four radio events exhibiting characteristics different from type IV radio bursts. The solar-wind structures at L1 after the 32 SSCs are 12 magnetic clouds (MCs), 6 interplanetary coronal mass ejections (ICMEs) without an MC structure, 4 miscellaneous structures, which cannot unambiguously be classified as ICMEs, 5 corotating or stream interaction regions (CIRs/SIRs), one CIR caused two SSCs, and 4 shock events; note than one CIR caused two SSCs. The 11 MCs listed in 3 or more MC catalogs covering the year 2002 are associated with SSCs. For the three most intense geomagnetic storms (based on Dst minima) related to MCs, we note two sudden increases of the Dst, at the arrival of the sheath and the arrival of the MC itself. In terms of geoeffectiveness, the relation between the CME speed and the magnetic-storm intensity, as characterized using the Dst magnetic index, is very complex, but generally CMEs with velocities at the Sun larger than 1000 km s−1 have larger probabilities to trigger moderate or intense storms. The most geoeffective events are MCs, since 92% of them trigger moderate or intense storms, followed by ICMEs (33%). At best, CIRs/SIRs only cause weak storms. We show that these geoeffective events (ICMEs or MCs) trigger an increased and combined auroral kilometric radiation (AKR) and non-thermal continuum (NTC) wave activity in the magnetosphere, an enhanced convection in the ionosphere, and a stronger response in the thermosphere. However, this trend does not appear clearly in the coupling functions, which exhibit relatively weak correlations between the solar-wind energy input and the amplitude of various geomagnetic indices, whereas the role of the southward component of the solar-wind magnetic field is confirmed. Some saturation appears for Dst values <−100<−100< -100 nT on the integrated values of the polar and auroral indices. |
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Programme |
139,312 |
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Bachelor's thesis |
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Edition |
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ISSN |
1573-093X |
ISBN |
1573-093X |
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Approved |
yes |
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Call Number |
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Serial |
7013 |
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| Permanent link to this record |
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Author |
Klein K-L, Trottet G, Samwel S, Malandraki O, |
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Title |
Particle Acceleration and Propagation in Strong Flares without Major Solar Energetic Particle Events
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Type |
Journal Article |
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Year |
2011 |
Publication |
Solar Physics |
Abbreviated Journal |
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Volume |
269 |
Issue |
2 |
Pages |
309-333 |
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Keywords |
Physics and Astronomy, |
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Abstract |
Solar energetic particles (SEPs) detected in space are statistically associated with flares and coronal mass ejections (CMEs). But it is not clear how these processes actually contribute to the acceleration and transport of the particles. The present work addresses the question why flares accompanied by intense soft X-ray bursts may not produce SEPs detected by observations with the GOES spacecraft. We consider all X-class X-ray bursts between 1996 and 2006 from the western solar hemisphere. 21 out of 69 have no signature in GOES proton intensities above 10 MeV, despite being significant accelerators of electrons, as shown by their radio emission at cm wavelengths. The majority (11/20) has no type III radio bursts from electron beams escaping towards interplanetary space during the impulsive flare phase. Together with other radio properties, this indicates that the electrons accelerated during the impulsive flare phase remain confined in the low corona. This occurs in flares with and without a CME. Although GOES saw no protons above 10 MeV at geosynchronous orbit, energetic particles were detected in some (4/11) confined events at Lagrangian point L1 aboard ACE or SoHO. These events have, besides the confined microwave emission, dm-m wave type II and type IV bursts indicating an independent accelerator in the corona. Three of them are accompanied by CMEs. We conclude that the principal reason why major solar flares in the western hemisphere are not associated with SEPs is the confinement of particles accelerated in the impulsive phase. A coronal shock wave or the restructuring of the magnetically stressed corona, indicated by the type II and IV bursts, can explain the detection of SEPs when flare-accelerated particles do not reach open magnetic field lines. But the mere presence of these radio signatures, especially of a metric type II burst, is not a sufficient condition for a major SEP event. |
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Bachelor's thesis |
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Springer Netherlands |
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0038-0938 |
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yes |
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3577 |
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