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| Author | Thierry Boulinier | ||||
| Title | Avian influenza spread and seabird movements between colonies | Type | Journal | ||
Year  |
2023 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | |
| Volume | 38 | Issue | 5 | Pages | 391-395 |
| Keywords | colonial breeding foraging HPAI H5N1 migration movement ecology prospecting spatial disease dynamics | ||||
| Abstract | |||||
| Programme | 333,1151 | ||||
| Campaign | |||||
| Address | |||||
| 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 | 0169-5347 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8502 | |||
| Permanent link to this record | |||||
| Author | Tifenn Le Bris, Guilhem Barruol, Emmanuel Le Meur, Florent Gimbert, Dimitri Zigone | ||||
| Title | Monitoring the cryoseismic activity of the Astrolabe glacier, Terre Adélie, Antarctica | Type | Peer-reviewed symposium | ||
| Year |
2023 | Publication | Copernicus meetings | Abbreviated Journal | |
| Volume | EGU23-7489 | Issue | Pages | ||
| Keywords | |||||
| Abstract | In coastal Antarctica, outlet glaciers exhibit complex dynamics materialized by intense internal deformation, enhanced basal sliding and strong thermo-mechanical interactions with the ocean. Here we aim to use seismic observations to unravel these various processes and their link with glacier and ocean dynamics. As part of the SEIS-ADELICE project (2020-2024) supported by the French Polar Institute IPEV, in January 2022 we deployed four permanent and six temporary (1 month long) broadband seismic stations on and around the Astrolabe Glacier (Terre Adélie, East Antarctica), as well as four ocean-bottom seismometers at sea near the terminus of the floating tongue. In January 2023 we will be supplementing this setup by a temporary network of 50 seismic nodes above the grounding line of the glacier. Preliminary detection and classification of seismic events reveals a wide variety of cryo-seismic signals. The most pervasive events correspond to icequakes, are located close to the surface, and exhibit clear tidal modulation. We interpret these events as being generated by the brittle fracturing of ice associated with crevasse opening. We also observe numerous short and similar repetitive events of much lower amplitude that are located at few restricted locations near the ice-bedrock interface. These events are likely produced by basal stick-slip over punctual bedrock asperities. Finally, we observe glacial tremors which could result from hydraulic sources at the ice-bedrock interface, although further analysis is required to confirm this hypothesis. This preliminary work provides useful grounds for deeper analysis to be done in the future on source characteristics and their more quantitative links with glacier dynamics. |
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| Programme | 411 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | EGU23-7489 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8545 | |||
| Permanent link to this record | |||||
| Author | Timothée Zidat, Marianne Gabirot, Francesco Bonadonna, Carsten T. Müller | ||||
| Title | Homing and Nest Recognition in Nocturnal Blue Petrels: What Scent May Attract Birds to their Burrows? | Type | Journal | ||
| Year |
2023 | Publication | Journal of Chemical Ecology | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | Homing Behavior Nest Air Odor Olfaction Orientation Procellariform Seabirds TD-GC-TOF-MS | ||||
| Abstract | Hypogean petrels return to the same nest burrow to breed on remote islands during the summer months. Their nocturnal behavior at the colony, strong musky odor and olfactory anatomy suggest an important role of olfaction in homing behavior and nest recognition. Behavioral experiments showed that olfactory cues are sufficient to allow nest identification, suggesting a stabile chemical signature emanating from burrows and facilitating nest recognition. However, the chemical nature and sources of this odor remain unknown. To better understand the nest odor composition, we analyzed volatile organic compounds (VOCs) of nests of blue petrels (Halobaena caerulea) derived from three different odor sources: nest air, nest material and feather samples. We also compared, during two successive years, VOCs from burrows with an incubating breeder on the nest, and burrows used during the breeding season by blue petrels but shortly temporally unoccupied by breeders. We found that the nest air odor was mainly formed by the owners’ odor, which provided an individual chemical label for nests that appeared stabile over the breeding season. These findings, together with the previous homing behavioral studies showing an essential role of the sense of smell in blue petrels, strongly suggest that the scent emanating from burrows of blue petrels provides the information that facilitates nest recognition and homing. | ||||
| Programme | 354 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1573-1561 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8630 | |||
| Permanent link to this record | |||||
| Author | Tracey L. Hammer, Pierre Bize, Benoit Gineste, Jean-Patrice Robin, René Groscolas, Vincent A. Viblanc | ||||
| Title | Disentangling the “many-eyes”, “dilution effect”, “selfish herd”, and “distracted prey” hypotheses in shaping alert and flight initiation distance in a colonial seabird | Type | Journal | ||
| Year |
2023 | Publication | Behavioural Processes | Abbreviated Journal | |
| Volume | 210 | Issue | Pages | 104919 | |
| Keywords | Antipredator behaviour Escape flight distance Optimal escape decisions Predation risk Predator-prey decision Risk taking | ||||
| Abstract | Group living is thought to have important antipredator benefits for animals, owing to the mechanisms of shared vigilance (“many-eyes” hypothesis), risk dilution (“dilution effect” hypothesis), and relative safety in the center of the group (“selfish herd” hypothesis). However, it can also incur costs since social stimuli, such as conspecific aggression, may distract individuals from anti-predator behavior (“distracted prey” hypothesis). We simultaneously evaluated how these four different hypotheses shape anti-predator behaviors of breeding king penguins (Aptenodytes patagonicus), which aggregate into large colonies, experience frequent aggressive social interactions, and are regularly exposed to predation by giant petrels (Macronectes sp.) and brown skuas (Catharacta loonbergi) when breeding on land. We approached 200 incubating penguins at four different periods of the breeding season across a range of overall increasing colony densities. We measured the distance at which focal birds detected the approaching threat (alert distance: AD), whether birds decided to flee or not, and the distance of flight initiation (flight initiation distance: FID, viz. the bird attempting to walk away with its egg on its feet). We quantified relative local neighbor density, centrality within the colony (rank), and the number of aggressions the focal bird emitted towards neighbors during the approach. We found that birds engaged in aggressive conflicts with neighbors were less likely to flee, and that increasing relative local neighbor density at low and medium overall colony density resulted in a decrease in bird AD, both supporting the “distracted prey” hypothesis. However, at maximal overall colony density, increasing relative local neighbor density resulted in longer AD, supporting the “many-eyes” hypothesis. We found no support for the “dilution effect” and “selfish herd” hypotheses, and no effects of any hypothesis on FID. | ||||
| Programme | 119 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0376-6357 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8678 | |||
| Permanent link to this record | |||||
| Author | Trifon Trifonov, Rafael Brahm, Andrés Jordán, Christian Hartogh, Thomas Henning, Melissa J. Hobson, Martin Schlecker, Saburo Howard, Finja Reichardt, Nestor Espinoza, Man Hoi Lee, David Nesvorny, Felipe I. Rojas, Khalid Barkaoui, Diana Kossakowski, Gavin Boyle, Stefan Dreizler, Martin Kürster, René Heller, Tristan Guillot, Amaury H. M. J. Triaud, Lyu Abe, Abdelkrim Agabi, Philippe Bendjoya, Nicolas Crouzet, Georgina Dransfield, Thomas Gasparetto, Maximilian N. Günther, Wenceslas Marie-Sainte, Djamel Mékarnia, Olga Suarez, Johanna Teske, R. Paul Butler, Jeffrey D. Crane, Stephen Shectman, George R. Ricker, Avi Shporer, Roland Vanderspek, Jon M. Jenkins, Bill Wohler, Karen A. Collins, Kevin I. Collins, David R. Ciardi, Thomas Barclay, Ismael Mireles, Sara Seager, Joshua N. Winn | ||||
| Title | TOI-2525 b and c: A Pair of Massive Warm Giant Planets with Strong Transit Timing Variations Revealed by TESS* | Type | Journal | ||
| Year |
2023 | Publication | The Astronomical Journal | Abbreviated Journal | |
| Volume | 165 | Issue | 4 | Pages | 179 |
| Keywords | |||||
| Abstract | The K-type star TOI-2525 has an estimated mass of M = M ⊙ and radius of R = R ⊙ observed by the TESS mission in 22 sectors (within sectors 1 and 39). The TESS light curves yield significant transit events of two companions, which show strong transit timing variations (TTVs) with a semiamplitude of ∼6 hr. We performed TTV dynamical and photodynamical light-curve analysis of the TESS data combined with radial velocity measurements from FEROS and PFS, and we confirmed the planetary nature of these companions. The TOI-2525 system consists of a transiting pair of planets comparable to Neptune and Jupiter with estimated dynamical masses of m b = and m c = M Jup, radii of r b = and r c = R Jup, and orbital periods of P b = and P c = days for the inner and outer planet, respectively. The period ratio is close to the 2:1 period commensurability, but the dynamical simulations of the system suggest that it is outside the mean-motion resonance (MMR) dynamical configuration. Object TOI-2525 b is among the lowest-density Neptune-mass planets known to date, with an estimated median density of ρ b = g cm−3. The TOI-2525 system is very similar to the other K dwarf systems discovered by TESS, TOI-2202 and TOI-216, which are composed of almost identical K dwarf primaries and two warm giant planets near the 2:1 MMR. | ||||
| Programme | 1066 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1538-3881 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8646 | |||
| Permanent link to this record | |||||
| Author | Vaissière Marie | ||||
| Title | Invasions biologiques : de quelle manière les phénomènes de tris spatiaux modulent-ils la diversité fonctionnelle des individus le long d’un gradient d’invasion ? | Type | Master 1 | ||
| Year |
2023 | Publication | Rapport de stage de master 1 imabee, univ rennes | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | |||||
| Abstract | |||||
| Programme | 136 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8755 | |||
| Permanent link to this record | |||||
| Author | William Jouanneau, Don-Jean Léandri-Breton, Dorte Herzke, Børge Moe, Vladimir A. Nikiforov, Marie Pallud, Charline Parenteau, Geir W. Gabrielsen, Olivier Chastel | ||||
| Title | Does contaminant exposure disrupt maternal hormones deposition? A study on per- and polyfluoroalkyl substances in an Arctic seabird | Type | Journal | ||
| Year |
2023 | Publication | Science of The Total Environment | Abbreviated Journal | |
| Volume | 868 | Issue | Pages | 161413 | |
| Keywords | Black-legged kittiwake Corticosterone Maternal effect PFAS Testosterone Thyroid hormones | ||||
| Abstract | Maternal effects are thought to be essential tools for females to modulate offspring development. The selective deposition of avian maternal hormones could therefore allow females to strategically adjust the phenotype of their offspring to the environmental situation encountered. However, at the time of egg formation, several contaminants are also transferred to the egg, including per- and polyfluoroalkyl substances (PFAS) which are ubiquitous organic contaminants with endocrine disrupting properties. It is, however, unknown if they can disrupt maternal hormone deposition. In this study we explored relationships between female PFAS burden and maternal deposition in the eggs of steroids (dihydrotestosterone, androstenedione and testosterone), glucocorticoids (corticosterone) and thyroid hormones (triiodothyronine and thyroxine) in a population of the Arctic-breeding black-legged kittiwake (Rissa tridactyla). Egg yolk hormone levels were unrelated to female hormone plasma levels. Second-laid eggs had significantly lower concentrations of androstenedione than first-laid eggs. Triiodothyronine yolk levels were decreasing with increasing egg mass but increasing with increasing females' body condition. Testosterone was the only transferred yolk hormone correlated to maternal PFAS burden: specifically, we found a positive correlation between testosterone in yolks and circulating maternal perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDcA) and perfluoroundecanoic acid (PFUnA) in first-laid eggs. This correlative study provides a first insight into the potential of some long-chain perfluoroalkyl acids to disrupt maternal hormones deposition in eggs and raises the question about the consequences of increased testosterone deposition on the developing embryo. | ||||
| Programme | 330 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0048-9697 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8534 | |||
| Permanent link to this record | |||||
| Author | Y. Klanten, R.-M. Couture, K. S. Christoffersen, W. F. Vincent, D. Antoniades | ||||
| Title | Oxygen Depletion in Arctic Lakes: Circumpolar Trends, Biogeochemical Processes, and Implications of Climate Change | Type | Journal | ||
| Year |
2023 | Publication | Global Biogeochemical Cycles | Abbreviated Journal | |
| Volume | 37 | Issue | 5 | Pages | e2022GB007616 |
| Keywords | Arctic lakes biochemical processes climate change dissolved oxygen freshwater meta-analysis | ||||
| Abstract | Polar amplification of climate change has the potential to cause large-scale shifts in the dissolved oxygen (DO) dynamics of Arctic lakes, with implications for fish survival, greenhouse gas production, and drinking water quality. While DO is also a sentinel of environmental changes of physical, chemical, and biological nature (e.g., ice cover, temperature, dissolved organic carbon, photosynthesis, and respiration), no synthesis exists of current knowledge of DO dynamics across the diverse freshwater systems of the Arctic. We thus conducted a systematic review of the literature that yielded DO data from 167 sites north of the Subarctic limit (based on vegetation zones), spanning 76 years and including 40 sites with time series. The compilation revealed insufficient observations for adequate representativeness of oxygen dynamics over Arctic ecosystem gradients. We described the main processes controlling DO budgets of Arctic lakes and tested relationships of summer oxygen depletion with maximum depth and latitude. The meta-analysis showed that most sites with low O2 concentrations were shallow (<10 m) and situated toward the southern end of the latitudinal gradient. Permanently stratified lakes with deep, perennially anoxic basins were located toward the northern end of the gradient. By way of a conceptual model, we identified the direct and indirect drivers and mechanisms that lead to changes in oxygen budgets in the context of the warming Arctic. This comprehensive update on available data allowed us to suggest future research directions and recommend the use of moored instruments for continuous all-season observations, combined with modeling, remote sensing, and paleo-reconstructions. | ||||
| Programme | 1042 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1944-9224 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8633 | |||
| Permanent link to this record | |||||
| Author | Yves Cherel, Colette Trouvé, Paco Bustamante | ||||
| Title | Cephalopod prey of light-mantled sooty albatross Phoebetria palpebrata, resource partitioning amongst Kerguelen albatrosses, and teuthofauna of the southern Indian Ocean | Type | Journal | ||
| Year |
2023 | Publication | Deep Sea Research Part I: Oceanographic Research Papers | Abbreviated Journal | |
| Volume | 198 | Issue | Pages | 104082 | |
| Keywords | Antarctica Bio-indication Procellariiformes Seabirds Southern Ocean Squids Stable isotopes | ||||
| Abstract | The cephalopod diet of the light-mantled sooty albatross Phoebetria palpebrata was determined for the first time at the subantarctic Kerguelen Islands by sorting ∼7000 accumulated beaks from 66 regurgitated boluses. Twenty-two taxa were identified, including four dominant squid species that are all endemic to the Southern Ocean: Galiteuthis glacialis (49.8% of the lower beaks) Psychroteuthis glacialis (18.5%), Martialia hyadesi (16.2%) and Moroteuthopsis longimana (6.9%). Beak δ13C values indicated that all adult P. glacialis, almost all juvenile M. longimana, and most adult G. glacialis were caught in Antarctic waters, while albatrosses preyed upon juvenile M. hyadesi in subantarctic waters. Comparative analysis of lower beaks accumulated in food samples of Kerguelen albatrosses showed that the four main sympatric albatross species segregate primarily by species-specific foraging grounds. Light-mantled sooty albatross feed on the Antarctic P. glacialis, wandering albatross Diomedea exulans on subantarctic and subtropical histioteuthids (41.4%), and grey-headed albatross Thalassarche chrysostoma and black-browed albatross T. melanophris on subantarctic ommastrephids (69.3% and 65.7%, respectively), with black-browed albatross also preying upon neritic endemic octopuses (17.6%). Cephalopod prey of Kerguelen albatrosses highlight the abundance and importance of some squids in the functioning of the pelagic ecosystem of the southern Indian Ocean, such as ommastrephids, M. longimana, P. glacialis, Histioteuthis atlantica, H. eltaninae, and G. glacialis. Based on the diet of the light-mantled sooty albatross, P. glacialis appears common in high-Antarctic waters of the southern Indian Ocean, whereas the poorly known Psychroteuthis sp. B (Imber) is evidently present in Antarctic waters south of the Kerguelen Islands. | ||||
| Programme | 109 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0967-0637 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8532 | |||
| Permanent link to this record | |||||
| Author | Zhendong Zhang, Jessica C. E. Irving, Frederik J. Simons, Tariq Alkhalifah | ||||
| Title | Seismic evidence for a 1000 km mantle discontinuity under the Pacific | Type | Journal | ||
| Year |
2023 | Publication | Nature Communications | Abbreviated Journal | |
| Volume | 14 | Issue | 1 | Pages | 1714 |
| Keywords | Geophysics Seismology | ||||
| Abstract | Seismic discontinuities in the mantle are indicators of its thermo-chemical state and offer clues to its dynamics. Ray-based seismic methods, though limited by the approximations made, have mapped mantle transition zone discontinuities in detail, but have yet to offer definitive conclusions on the presence and nature of mid-mantle discontinuities. Here, we show how to use a wave-equation-based imaging method, reverse-time migration of precursors to surface-reflected seismic body waves, to uncover both mantle transition zone and mid-mantle discontinuities, and interpret their physical nature. We observe a thinned mantle transition zone southeast of Hawaii, and a reduction in impedance contrast around 410 km depth in the same area, suggesting a hotter-than-average mantle in the region. Here, we furthermore reveal a 4000–5000 km-wide reflector in new images of the mid mantle below the central Pacific, at 950–1050 km depth. This deep discontinuity exhibits strong topography and generates reflections with polarity opposite to those originating at the 660 km discontinuity, implying an impedance reversal near 1000 km. We link this mid-mantle discontinuity to the upper reaches of deflected mantle plumes upwelling in the region. Reverse-time migration full-waveform imaging is a powerful approach to imaging Earth’s interior, capable of broadening our understanding of its structure and dynamics and shrinking modeling uncertainties. | ||||
| Programme | 133 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8549 | |||
| Permanent link to this record | |||||