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Author |
Christophe Barbraud, Karine Delord, Charles A. Bost, Adrien Chaigne, Cédric Marteau, Henri Weimerskirch |
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Title |
Population trends of penguins in the French Southern Territories |
Type |
Journal |
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Year |
2020 |
Publication |
Polar Biology |
Abbreviated Journal |
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Volume |
43 |
Issue |
7 |
Pages |
835-850 |
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Keywords |
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Abstract |
Penguins are important top consumers in marine food webs and are one of the most threatened bird families, especially by climate change and food web alterations by marine fisheries. Yet, long-term population trends are lacking or are uncertain for many populations. Seven species of penguins breeding at the French Southern Territories in the southern Indian Ocean on the Crozet, Kerguelen, Saint-Paul–Amsterdam archipelagos and in Terre Adélie/Adelie Land, Antarctica are monitored regularly. This monitoring started in the early 1950s and most populations have been surveyed during the past four years, allowing assessments of population trends. King penguins increased at nearly all breeding sites within the Crozet and Kerguelen archipelagos. Emperor penguins have decreased at Terre Adélie/Adelie Land, with a partial recovery of the colony during the 2010s. Gentoo penguin populations at Crozet and Kerguelen are highly variable but stable. Adélie penguins have been increasing in Terre Adélie/Adelie Land. The trends in eastern rockhopper penguins vary between colonies and archipelagos. Northern rockhopper penguins have continuously decreased in numbers at Amsterdam Island, but appear to have increased at the nearby Saint-Paul Island. Macaroni penguins have first increased and then stabilized since the 2000s at Kerguelen and are stable at the Crozet Islands. Overall, most penguin populations breeding in the French Southern Territories increased or were stable over the past 30–60 years, with the exception of the northern rockhopper penguin, king and gentoo penguins on Crozet and the emperor penguin. The ecological reasons for these trends are poorly understood and require further investigation. |
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Programme |
109,394 |
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Bachelor's thesis |
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Edition |
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ISSN |
1432-2056 |
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Approved |
yes |
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Call Number |
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Serial |
7639 |
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Author |
Juliana A. Vianna, Flávia A. N. Fernandes, María José Frugone, Henrique V. Figueiró, Luis R. Pertierra, Daly Noll, Ke Bi, Cynthia Y. Wang-Claypool, Andrew Lowther, Patricia Parker, Celine Le Bohec, Francesco Bonadonna, Barbara Wienecke, Pierre Pistorius, Antje Steinfurth, Christopher P. Burridge, Gisele P. M. Dantas, Elie Poulin, W. Brian Simison, Jim Henderson, Eduardo Eizirik, Mariana F. Nery, Rauri C. K. Bowie |
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Title |
Genome-wide analyses reveal drivers of penguin diversification |
Type |
Journal |
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Year |
2020 |
Publication |
Proceedings of the National Academy of Sciences |
Abbreviated Journal |
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Volume |
117 |
Issue |
36 |
Pages |
22281-22292 |
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Keywords |
ancestral distribution ancestral niche Antarctica genome penguin |
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Abstract |
Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation. |
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Programme |
137,354 |
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Bachelor's thesis |
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ISSN |
0027-8424, 1091-6490 |
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yes |
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Call Number |
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Serial |
7780 |
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Author |
Agnès Lewden, Andreas Nord, Batshéva Bonnet, Florent Chauvet, André Ancel, Dominic J. McCafferty |
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Title |
Body surface rewarming in fully and partially hypothermic king penguins |
Type |
Journal |
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Year |
2020 |
Publication |
Journal of Comparative Physiology B |
Abbreviated Journal |
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Volume |
190 |
Issue |
5 |
Pages |
597-609 |
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Keywords |
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Abstract |
Penguins face a major thermal transition when returning to land in a hypothermic state after a foraging trip. Uninsulated appendages (flippers and feet) could provide flexible heat exchange during subsequent rewarming. Here, we tested the hypothesis that peripheral vasodilation could be delayed during this recovery stage. To this end, we designed an experiment to examine patterns of surface rewarming in fully hypothermic (the cloaca and peripheral regions (here; flippers, feet and the breast) < 37 °C) and partially hypothermic (cloaca at normothermia ≥ 37 °C, but periphery at hypothermia) king penguins (Aptenodytes patagonicus) when they rewarmed in the laboratory. Both groups rewarmed during the 21 min observation period, but the temperature changes were larger in fully than in partially hypothermic birds. Moreover, we observed a 5 min delay of peripheral temperature in fully compared to partially hypothermic birds, suggesting that this process was impacted by low internal temperature. To investigate whether our laboratory data were applicable to field conditions, we also recorded surface temperatures of free-ranging penguins after they came ashore to the colony. Initial surface temperatures were lower in these birds compared to in those that rewarmed in the laboratory, and changed less over a comparable period of time on land. This could be explained both by environmental conditions and possible handling-induced thermogenesis in the laboratory. Nevertheless, this study demonstrated that appendage vasodilation is flexibly used during rewarming and that recovery may be influenced by both internal temperature and environmental conditions when penguins transition from sea to land. |
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394 |
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ISSN |
1432-136X |
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Approved |
yes |
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Call Number |
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Serial |
7659 |
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Permanent link to this record |
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Author |
Rémi Bigonneau, Romain Bazire, Cédric Marteau, Christophe Barbraud, Joan Ferrer-Obiol, Karine Delord |
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Title |
First record of Black-winged Pratincole Glareola nordmanni for Amsterdam Island, Indian Ocean |
Type |
Journal |
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Year |
2020 |
Publication |
African Bird Club |
Abbreviated Journal |
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Volume |
27 |
Issue |
1 |
Pages |
94-95 |
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Keywords |
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Abstract |
Première mention de la Glaréole à ailes noires Glareola nordmanni pour l’Île Amsterdam, Océan Indien. Une Glaréole à ailes noires Glareola nordmanni de premier hiver à été observée sur l’Île Amsterdam, dans le sud de l’Océan indien, les 12–16 novembre 2013. Il s’agît de la première donnée de cette espèce paléarctique pour l’île. Les mentions antérieures les plus proches proviennent de l’île d’Alphonse, aux Seychelles, à environ 4.200 km de l’Île Amsterdam. |
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Programme |
109 |
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Thesis |
Bachelor's thesis |
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Approved |
yes |
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Call Number |
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Serial |
3031 |
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Permanent link to this record |
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Author |
Najat Bhiry, Dominique Marguerie, Tommy Weetaluktuk, Pierre M. Desrosiers, Dominique Todisco, Myosotis Desroches Bourgon, David Aoustin |
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Title |
Dorset and Thule Inuit occupations of Qikirtajuaq (Smith Island), Nunavik, Canada: a palaeoecological approach |
Type |
Journal |
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Year |
2020 |
Publication |
Boreas |
Abbreviated Journal |
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Volume |
50 |
Issue |
3 |
Pages |
826-843 |
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Keywords |
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Abstract |
Qikirtajuaq is a long island facing the Inuit village of Akulivik on the northeastern coast of Hudson Bay (Canada) that is rich in archaeological sites. Kangiakallak-1 (JeGn-2), one of the main sites on this island, is a large multicomponent site that includes Dorset and Thule Inuit winter houses. This study documents the dynamics of palaeoenvironmental conditions in the successive occupations of the Kangiakallak-1 settlement based on plant macrofossils, pollen and non-pollen palynomorph analyses and archaeological research. The data indicate that Dorset inhabitants constructed their dwelling at about 772 cal. a BP. The site was reused by the Thule Inuit a few decades later, starting at about 671 cal. a BP. Thus, Kangiakallak-1 is one of the few sites, at least in Nunavik (northern Québec, Canada), that were rapidly reoccupied by the Thule Inuit after the departure of the Dorset inhabitants, which indicates a possible overlap between the two cultures in the Akulivik region. The palaeoecological data show that both Dorset and Thule inhabitants left clear footprints at the local scale in the form of several nitrophilous species that became established in and near the houses and persisted over a long period. The deposition of domestic waste (including bone fragments, skin, burnt fat and charcoal fragments) inside the subterranean dwellings fertilized the soil and led to the growth of unique nitrophilous plants. These changes transformed the houses into exceptional floristic refuges. |
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Programme |
1080 |
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Series Issue |
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Edition |
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ISSN |
1502-3885 |
ISBN |
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Approved |
yes |
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Call Number |
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Serial |
8292 |
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Permanent link to this record |
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Author |
Chuxian Li, Jeroen E. Sonke, Gaël Le Roux, Natalia Piotrowska, Nathalie Van der Putten, Stephen J. Roberts, Tim Daley, Emma Rice, Roland Gehrels, Maxime Enrico, Dmitri Mauquoy, Thomas P. Roland, François De Vleeschouwer |
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Title |
Unequal Anthropogenic Enrichment of Mercury in Earth’s Northern and Southern Hemispheres |
Type |
Journal |
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Year |
2020 |
Publication |
ACS Earth and Space Chemistry |
Abbreviated Journal |
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Volume |
4 |
Issue |
11 |
Pages |
2073-2081 |
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Keywords |
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Abstract |
Remote Northern Hemisphere (NH) and Southern Hemisphere (SH) lake sediment and peat records of mercury (Hg) deposition have shown a ×3 to ×5 Hg enrichment since pre-industrial times (<1880 AD), leading to the perception that global atmospheric Hg enrichment is moderate and uniform across the hemispheres. Anthropogenic Hg emissions in the NH are, however, approximately 4 times higher than those in the SH. Here, we reconstruct atmospheric Hg deposition in four remote SH peatlands and review sediment and peat Hg records from both hemispheres. We observe a ×4 all-time enrichment in SH Hg deposition from pre-anthropogenic (<1450 AD) to the late 20th-century periods, which is lower than the large ×16 all-time enrichment in NH Hg deposition. We attribute this difference to lower anthropogenic Hg emissions in the SH, and higher natural atmospheric SH Hg concentrations, supported by ×2 higher natural background Hg accumulation in SH peat records. We suggest that the higher SH natural atmospheric Hg deposition reflects the SH land–ocean distribution, and is driven by important SH marine Hg emissions. Our findings indicate that atmospheric Hg background levels and anthropogenic enrichment in both hemispheres are different and should be taken into account in international Hg assessments and environmental policy. |
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Programme |
1065,1133 |
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Thesis |
Bachelor's thesis |
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yes |
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Call Number |
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Serial |
7791 |
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Permanent link to this record |
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Author |
Helle A. Pedersen, Nicolas Leroy, Dimitri Zigone, Martin Vallée, Adam T. Ringler, David C. Wilson |
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Title |
Using Component Ratios to Detect Metadata and Instrument Problems of Seismic Stations: Examples from 18 Yr of GEOSCOPE Data |
Type |
Journal |
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Year |
2020 |
Publication |
Seismological research letters |
Abbreviated Journal |
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Volume |
91 |
Issue |
1 |
Pages |
272-286 |
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Keywords |
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Abstract |
Replacement or deterioration of seismic instruments and the evolution of the installation conditions and sites can alter the seismic signal in very subtle ways; therefore, it is notoriously difficult to monitor the signal quality of permanent seismic stations. We present a simple way to characterize and monitor signal quality, using energy ratios between each pair of the three components, as a complement to existing methods. To calculate stable daily energy ratios over a large frequency range (0.01–5 Hz), we use the daily median energy ratio over all 5 min windows within the day. The method is applied to all GEOSCOPE stations, for continuous BH channel data collected since 2001. We show applications to identify past gain problems (stations ROCAM and CRZF), to provide feedback after field interventions at remote sites (Antarctic station DRV), and to shed light on complex instrument problems (stations ECH and KIP). Our results show that component energy ratios have excellent time resolution and that they are visually simple for identification of problems. They can be used both for ongoing continuous monitoring of the signal quality, or as a tool to identify past problems. The Python code to produce the results in this work and the Python code for daily monitoring used by GEOSCOPE are available (see Data and Resources). |
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Programme |
133 |
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yes |
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Call Number |
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Serial |
7672 |
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Permanent link to this record |
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Author |
Eva Fuglei, John-André Henden, Chris T. Callahan, Olivier Gilg, Jannik Hansen, Rolf A. Ims, Arkady P. Isaev, Johannes Lang, Carol L. McIntyre, Richard A. Merizon, Oleg Y. Mineev, Yuri N. Mineev, Dave Mossop, Olafur K. Nielsen, Erlend B. Nilsen, Åshild Ønvik Pedersen, Niels Martin Schmidt, Benoît Sittler, Maria Hørnell Willebrand, Kathy Martin |
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Title |
Circumpolar status of Arctic ptarmigan: Population dynamics and trends |
Type |
Journal |
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Year |
2020 |
Publication |
Ambio |
Abbreviated Journal |
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Volume |
49 |
Issue |
3 |
Pages |
749-761 |
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Keywords |
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Abstract |
Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3–6 years and long 9–12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs. |
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1036 |
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Edition |
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ISSN |
1654-7209 |
ISBN |
1654-7209 |
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yes |
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Call Number |
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Serial |
7630 |
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Permanent link to this record |
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Author |
Alice Carravieri, Paco Bustamante, Pierre Labadie, Hélène Budzinski, Olivier Chastel, Yves Cherel |
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Title |
Trace elements and persistent organic pollutants in chicks of 13 seabird species from Antarctica to the subtropics |
Type |
Journal |
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Year |
2020 |
Publication |
Environment International |
Abbreviated Journal |
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Volume |
134 |
Issue |
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Pages |
105225 |
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Keywords |
Albatrosses; Mercury; Penguins; Petrels; Selenium; Stable isotopes |
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Abstract |
Seabirds from remote regions are mainly exposed to environmental contaminants from non-point contamination of their food webs. Pre-fledging seabird chicks are fed by their parents with marine prey captured in the vicinity of breeding colonies. Contaminant concentrations in tissues of pre-fledging chicks can thus be mostly related to local dietary sources, and have the potential to unravel spatial patterns of environmental contamination in marine ecosystems. Here, mercury (Hg), 13 other trace elements, and 18 persistent organic pollutants (POPs) were quantified in blood of chicks across four breeding locations that encompass a large latitudinal range in the southern Indian Ocean (from Antarctica, through subantarctic areas, to the subtropics), over a single breeding season. Thirteen species of penguins, albatrosses and petrels were studied, including endangered and near-threatened species, such as Amsterdam albatrosses and emperor penguins. Blood Hg burdens varied widely between species, with a factor of ~50 between the lowest and highest concentrations (mean ± SD, 0.05 ± 0.01 and 2.66 ± 0.81 µg g−1 dry weight, in thin-billed prions and Amsterdam albatrosses, respectively). Species relying on Antarctic waters for feeding had low Hg exposure. Concentrations of POPs were low in chicks, with the exception of hexachlorobenzene. Contaminant concentrations were mainly explained by species differences, but feeding habitat (inferred from δ13C values) and chicks’ body mass also contributed to explain variation. Collectively, our findings call for further toxicological investigations in Amsterdam albatrosses and small petrel species, because they were exposed to high and diverse sources of contaminants, and in macaroni penguins, which specifically showed very high selenium concentrations. Capsule Seabird chicks from four distant sites in the southern Indian Ocean had contrasted blood metallic and organic contaminant patterns depending on species, feeding habitat and body mass. |
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Programme |
109 |
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Thesis |
Bachelor's thesis |
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ISSN |
0160-4120 |
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yes |
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Call Number |
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Serial |
7674 |
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Permanent link to this record |
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Author |
Mario Lebrato, Dieter Garbe-Schönberg, Marius N. Müller, Sonia Blanco-Ameijeiras, Richard A. Feely, Laura Lorenzoni, Juan-Carlos Molinero, Karen Bremer, Daniel O. B. Jones, Debora Iglesias-Rodriguez, Dana Greeley, Miles D. Lamare, Aurelien Paulmier, Michelle Graco, Joan Cartes, Joana Barcelos e Ramos, Ana de Lara, Ricardo Sanchez-Leal, Paz Jimenez, Flavio E. Paparazzo, Susan E. Hartman, Ulrike Westernströer, Marie Küter, Roberto Benavides, Armindo F. da Silva, Steven Bell, Chris Payne, Solveig Olafsdottir, Kelly Robinson, Liisa M. Jantunen, Alexander Korablev, Richard J. Webster, Elizabeth M. Jones, Olivier Gilg, Pascal Bailly du Bois, Jacek Beldowski, Carin Ashjian, Nejib D. Yahia, Benjamin Twining, Xue-Gang Chen, Li-Chun Tseng, Jiang-Shiou Hwang, Hans-Uwe Dahms, Andreas Oschlies |
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Title |
Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean |
Type |
Book Chapter |
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Year |
2020 |
Publication |
Proceedings of the National Academy of Sciences |
Abbreviated Journal |
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Volume |
117 |
Issue |
36 |
Pages |
22281-22292 |
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Keywords |
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Abstract |
Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth–ocean–atmosphere dynamic exchange of elements. The ratios’ dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios’ variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect. |
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Bachelor's thesis |
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0027-8424, 1091-6490 |
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yes |
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7781 |
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