Suchergebnisse

McCoy, K. D. et al. ; Recent observations on the western Antarctic Peninsula have suggested that changing climatic conditions may be increasing pressure on breeding seabirds due to higher exploitation rates by the tick Ixodes uriae. Using data from 8 microsatellite markers and ticks from 6 Pygoscelis spp. colonies, we employed a population genetics approach to specifically test the hypothesis that I. uriae is expanding south-westward along the peninsula from the Subantarctic region. Contrary to expectations, tick genetic diversity was high within all colonies, and no remaining signal of colonisation events was evident. Although significant geographic genetic structure occurred among ticks from different colonies, these ectoparasites tended to belong to 2 major genetic groups, one found principally in south-western locations (Palmer Station area) and the other in more north-eastern areas (South Shetland Islands). More central colonies showed a mixture of ticks from each genetic group, suggesting that this area represents a hybridisation zone of ticks from 2 distinct origins. A subsequent clustering analysis, including ticks from 2 Subantarctic locations, did not reveal the source population for the northern peninsula group. Overall, our data refute the hypothesis of a recent south-westward expansion of I. uriae along the peninsula and suggest that this tick has been present at more southern latitudes for an extended period of time. Further studies on the distribution and genetic characteristics of this ectoparasite around Antarctica are now required to better understand the colonisation process and predict how changing environmental conditions may affect its presence and diversity in seabird colonies. © Inter-Research 2012. ; Financial support was provided by the European Regional Development Fund, the Ministerio de Ciencia e Innovacion from the Spanish Government (Projects POL2006-06635, POL2006-05175, CGL2004-01348, CGL2007-60369, CGL2009-11278/BOS, CMT 2011-24427) and the Agence National de la Recherche, France (ANR-06-JCJC-0095-01). ; Peer Reviewed

Penguins dominate the Antarctic avifauna. As key animals in the Antarctic ecosystem, they are monitored to evaluate the ecological status of this pristine and remote region and specifically, they have been used as effective bioindicators suitable for long-term monitoring of metals in the Antarctic environment. However, studies about the role of this emblematic organism could play in the recycling of trace metals (TMs) in the Antarctic ecosystem are very limited. In this study we evaluate, using the peer review research articles already published and our own findings, the distribution of metals (i.e., Ca, Fe, Al, Na, Zn, Mg, Cu, K, Cd, Mn, Sr, Cr, Ni, Pb, Hg, V, Ba, Co, La, Ag, Rb, Hf, Sc, Au and Cs) and metalloids (As and Sb), measured in different biotic matrices, with emphasis on guano, of the Chinstrap (Pygoscelis antarcticus), Adelie (Pygoscelis adeliae) and Gentoo (Pygoscelis papua) penguins. Regarding bioactive metals, the high concentrations (mu g g(-1) dry weight) of Cu (2.0 +/- 1.4) x 10(2), Fe (4.1 +/- 2.9) x 10(2), Mn (30 +/- 34) and Zn (210 +/- 90) reported in the guano from all the penguin species studied including our data, are of the same order of magnitude as those reported for whale feces (mu g g(-1) dry weight): Cu (2.9 +/- 2.4) x 10(2), Fe (1.5 +/- 1.4) x 10(2), Mn (28 +/- 17) and Zn (6.2 +/- 4.3) x 10(2), and one order of magnitude higher than the metal contents in krill (mu g g(-1) dry weight) of Cu (10.2 +/- 5.5), Fe (24 +/- 29) and Zn (13.5 +/- 1.7). This suggest that penguin's excretion products could be an important source of these essential elements in the surface water, with an estimated annual release on a breeding season for Cu, Fe, Mn, Zn respectively of 28, 56, 4 and 29 tons, for the Chinstrap, Adelie and Gentoo penguins. The results provide evidence on the potential influence of penguins recycling TMs in the surface layer of the water column. ; This research has been funded by the Spanish Government projects PIMETAN (ref. RTI2018-098048-B-I00) and PINGUFOR (ref. CTM201564720-R). E. Sparaventi is supported by the Spanish FPI grant (Ref: PRE2019-089679) and A. Rodriguez-Romero is supported by the Spanish grant, Juan de la Cierva Incorporacion (Ref: IJC2018-037545-I). We thank I. Carribero and M.C. Agullo for their support with the instrumental and methodological analyses. This research is part of POLARCSIC research initiative. Permissions to work and collect guano samples in the study area were granted by the Spanish Polar Committee. We thank the hospitality of the Spanish Antarctic Stations "Gabriel de Castilla" and "Juan Carlos I" and the transportation by the RV Hesperides. We also thank the logistic support by the Marine Technological Unit of CSIC.

Penguins dominate the Antarctic avifauna. As key animals in the Antarctic ecosystem, they are monitored to evaluate the ecological status of this pristine and remote region and specifically, they have been used as effective bioindicators suitable for long-term monitoring of metals in the Antarctic environment. However, studies about the role of this emblematic organism could play in the recycling of trace metals (TMs) in the Antarctic ecosystem are very limited. In this study we evaluate, using the peer review research articles already published and our own findings, the distribution of metals (i.e., Ca, Fe, Al, Na, Zn, Mg, Cu, K, Cd, Mn, Sr, Cr, Ni, Pb, Hg, V, Ba, Co, La, Ag, Rb, Hf, Sc, Au and Cs) and metalloids (As and Sb), measured in different biotic matrices, with emphasis on guano, of the Chinstrap (Pygoscelis antarcticus), Adélie (Pygoscelis adeliae) and Gentoo (Pygoscelis papua) penguins. Regarding bioactive metals, the high concentrations (μg g−1 dry weight) of Cu (2.0 ± 1.4) x 102, Fe (4.1 ± 2.9) x 102, Mn (30 ± 34) and Zn (210 ± 90) reported in the guano from all the penguin species studied including our data, are of the same order of magnitude as those reported for whale feces (μg g−1 dry weight): Cu (2.9 ± 2.4) x 102, Fe (1.5 ± 1.4) x 102, Mn (28 ± 17) and Zn (6.2 ± 4.3) x 102, and one order of magnitude higher than the metal contents in krill (μg g−1 dry weight) of Cu (10.2 ± 5.5), Fe (24 ± 29) and Zn (13.5 ± 1.7). This suggest that penguin's excretion products could be an important source of these essential elements in the surface water, with an estimated annual release on a breeding season for Cu, Fe, Mn, Zn respectively of 28, 56, 4 and 29 tons, for the Chinstrap, Adélie and Gentoo penguins. The results provide evidence on the potential influence of penguins recycling TMs in the surface layer of the water column. ; This research has been funded by the Spanish Government projects PIMETAN (ref. RTI2018-098048-B-I00) and PINGUFOR (ref. CTM2015-64720-R). E. Sparaventi is supported by the Spanish FPI grant (Ref: PRE2019-089679) and A. Rodríguez-Romero is supported by the Spanish grant, Juan de la Cierva Incorporación (Ref: IJC2018-037545-I). ; Peer reviewed

Penguins dominate the Antarctic avifauna. As key animals in the Antarctic ecosystem, they are monitored to evaluate the ecological status of this pristine and remote region and specifically, they have been used as effective bioindicators suitable for long-term monitoring of metals in the Antarctic environment. However, studies about the role of this emblematic organism could play in the recycling of trace metals (TMs) in the Antarctic ecosystem are very limited. In this study we evaluate, using the peer review research articles already published and our own findings, the distribution of metals (i.e., Ca, Fe, Al, Na, Zn, Mg, Cu, K, Cd, Mn, Sr, Cr, Ni, Pb, Hg, V, Ba, Co, La, Ag, Rb, Hf, Sc, Au and Cs) and metalloids (As and Sb), measured in different biotic matrices, with emphasis on guano, of the Chinstrap (Pygoscelis antarcticus), Ad´elie (Pygoscelis adeliae) and Gentoo (Pygoscelis papua) penguins. Regarding bioactive metals, the high concentrations (μg g− 1 dry weight) of Cu (2.0 ± 1.4) x 102 , Fe (4.1 ± 2.9) x 102 , Mn (30 ± 34) and Zn (210 ± 90) reported in the guano from all the penguin species studied including our data, are of the same order of magnitude as those reported for whale feces (μg g− 1 dry weight): Cu (2.9 ± 2.4) x 102 , Fe (1.5 ± 1.4) x 102 , Mn (28 ± 17) and Zn (6.2 ± 4.3) x 102 , and one order of magnitude higher than the metal contents in krill (μg g− 1 dry weight) of Cu (10.2 ± 5.5), Fe (24 ± 29) and Zn (13.5 ± 1.7). This suggest that penguin's excretion products could be an important source of these essential elements in the surface water, with an estimated annual release on a breeding season for Cu, Fe, Mn, Zn respectively of 28, 56, 4 and 29 tons, for the Chinstrap, Ad´elie and Gentoo penguins. The results provide evidence on the potential influence of penguins recycling TMs in the surface layer of the water column. ; Spanish Government project PIMETAN RTI2018-098048-B-I00 PINGUFOR CTM201564720-R Spanish Government PRE2019-089679 Spanish grant, Juan de la Cierva Incorporacion IJC2018-037545-I ; Versión publicada - versión final del editor

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pathogen has spread rapidly across the world, causing high numbers of deaths and significant social and economic impacts. SARS-CoV-2 is a novel coronavirus with a suggested zoonotic origin with the potential for cross-species transmission among animals. Antarctica can be considered the only continent free of SARS-CoV-2. Therefore, concerns have been expressed regarding the potential human introduction of this virus to the continent through the activities of research or tourism to minimise the effects on human health, and the potential for virus transmission to Antarctic wildlife. We assess the reverse-zoonotic transmission risk to Antarctic wildlife by considering the available information on host susceptibility, dynamics of the infection in humans, and contact interactions between humans and Antarctic wildlife. The environmental conditions in Antarctica seem to be favourable for the virus stability. Indoor spaces such as those at research stations, research vessels or tourist cruise ships could allow for more transmission among humans and depending on their movements between different locations the virus could be spread across the continent. Among Antarctic wildlife previous in silico analyses suggested that cetaceans are at greater risk of infection whereas seals and birds appear to be at a low infection risk. However, caution needed until further research is carried out and consequently, the precautionary principle should be applied. Field researchers handling animals are identified as the human group posing the highest risk of transmission to animals while tourists and other personnel pose a significant risk only when in close proximity (< 5 m) to Antarctic fauna. We highlight measures to reduce the risk as well as identify of knowledge gaps related to this issue. ; This work is an outcome of the Working Group of Wildlife Health Monitoring of the SCAR Expert Group of Birds and Marine Mammals. AB is supported by the Spanish Research Agency project (CTM2015-64720). AG is supported by the Defence Advanced Research Projects Agency (DARPA PREEMPT Cooperative Agreement No. D18AC00031). The content of the information does not necessarily reflect the position or the policy of the US government, and no official endorsement should be inferred. AV is supported by National Science Foundation (USA) Polar program (award # 1947040). CRM is supported by Australia's Integrated Marine Observing System. IMOS is enabled by the National Collaborative Research Infrastructure Strategy (NCRIS). It is operated by a consortium of institutions as an unincorporated joint venture, with the University of Tasmania as Lead Agent. JID is supported by Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Universidad Nacional de La Plata UNLP (N#859). VM is supported by National Science Foundation (USA) Polar program (PLR 1543459). TB is supported by CNRS, French Polar Institute Project ECOPATH (IPEV 1151), ZATA and OSU OREME. DGA is supported by INACH T-23-19 project. ; Peer reviewed

The polar regions provide valuable insights into the functioning of the Earth's regulating systems. Conducting field research in such harsh and remote environments requires strong international cooperation, extended planning horizons, sizable budgets and long-term investment. Consequently, polar research is particularly vulnerable to societal and economic pressures during periods of austerity. The global financial crisis of 2008, and the ensuing decade of economic slowdown, have already adversely affected polar research, and the current COVID-19 pandemic has added further pressure. In this article we present the outcomes of a community survey that aimed to assess the main barriers and success factors identified by academic researchers at all career stages in response to these global crises. The survey results indicate that the primary barriers faced by polar early and mid-career researchers (EMCRs) act at institutional level, while mitigating factors are developed at individual and group levels. Later career scientists report pressure toward taking early retirement as a means of institutions saving money, reducing both academic leadership and the often unrecognized but vital mentor roles that many play. Gender and social inequalities are also perceived as important barriers. Reorganization of institutional operations and more effective strategies for long-term capacity building and retaining of talent, along with reduction in non-research duties shouldered by EMCRs, would make important contributions toward ensuring continued vitality and innovation in the polar research community. ; BF received funding from the post-doctoral fellowships programme Beatriu de Pinós funded by the Secretary of Universities and Research (Government of Catalonia) and by the Horizon 2020 Programme of Research and Innovation of the European Union under the Marie Skłodowska-Curie grant agreement No. 801370 (Incorporation grant 2019 BP 00183) and the Juan de la Cierva Programme funded by the Ministry of Science and Innovation (Incorporation grant IJCI-2017-31478). PC and HJG were supported by NERC core funding to the BAS "Biodiversity, Evolution and Adaptation" Team. ; Peer reviewed

Over evolutionary time, pathogen challenge shapes the immunepheno type of the host to better respond to an incipient threat. The extent and direction of this selection pressure depend on the local pathogen composition, which is in turn determined by biotic and abiotic features of the environment. However, little is known about adaptation to local pathogen threats in wild animals. The Gentoo penguin (Pygoscelis papua) is a species complex that lends itself to the study of immune adaptation because of its circumpolar distribution over a large latitudinal range, with little or no admixture between ''different clades. Inthis study, we examine the diversity in a key family of innate immune genes-theToll-like receptors (TLRs)-across the range of the Gentoo penguin. The three TLRs that we investigated present varying levels of diversity, with TLR4 and TLR5 greatly exceeding the diversity of TLR7. We present evidence of positive selection in TLR4 and TLR5, which points to pathogen-driven adaptation to the local pathogen milieu. Finally, we demonstrate that two positively selected cosegregating sites in TLR5 are sufficient to alter the responsiveness of the receptor to its bacterial ligand, flagellin. Taken together, these results suggest that Gentoo penguins have experienced distinct pathogen-driven selection pressures in different environments, which may be important given the role of the Gentoo penguin as a sentinel species in some of the world's most rapidly changing environments. ; Oxford Clarendon Fund scholarship Biotechnology and Biological Sciences Research Council (BBSRC) BB/M011224/1 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) PIA ACT172065 Spanish Government CGL2007-60369 CTM2015-64720 Institut Polaire Francais Paul-Emile Victor (IPEV: Program 137) Institut Polaire Francais Paul-Emile Victor (IPEV: Program 354) Laboratoire International Associe 647 "BioSensib" (CSM/CNRS-University of Strasbourg) ALS