78 research outputs found
Validating the use of intrinsic markers in body feathers to identify inter-individual differences in non-breeding areas of northern fulmars
Acknowledgments We thank Claire Deacon, Gareth Norton and Andrea Raab for help with laboratory work at the University of Aberdeen, and Barry Thornton and Gillian Martin for running stable isotope analysis at the James Hutton Institute. Thanks to all involved in the collection and processing of dead fulmars through the North Sea plastic pollution project at IMARES, with special thanks to Jens-Kjeld Jensen, Bergur Olsen and Elisa Bravo Rebolledo for samples from the Faroe Islands and Susanne KĂźhn for those from Iceland. Thanks to Orkney Islands Council for access to Eynhallow and to all the fieldworkers involved in deployment and recovery of the GLS tags. All ringing work was carried out under permit from the BTO, and feather sampling was carried out under licence from the Home Office. We are grateful to James Fox of Migrate Technologies for recovering data from GLS loggers which would not download, and Richard Phillips and Janet Silk of BAS for advice on GLS analysis. We thank Deborah Dawson of the NERC Biomolecular Analysis Facility, University of Sheffield and Stuart Piertney of University of Aberdeen for molecular sexing of the fulmars. Lucy Quinn was supported by a NERC Studentship and additional funding to support fieldwork was gratefully received from Talisman Energy (UK) Ltd. We thank Yves Cherel and two anonymous reviewers for their constructive comments on the manuscript.Peer reviewedPublisher PD
Plastic ingestion by northern fulmars, Fulmarus glacialis, in Svalbard and Iceland, and relationships between plastic ingestion and contaminant uptake
Comment on âMarine plastic debris emits a keystone infochemical for olfactory foraging seabirdsâ by Savocaet al.
In their recent paper, Savoca and collaborators (2016) showed that plastic debris in the ocean may acquire a
dimethyl sulfide (DMS) signature from biofouling developing on their surface. According to them, DMS emission
may represent an olfactory trap for foraging seabirds, which explains patterns of plastic ingestion among procellariiform
seabirds. This hypothesis is appealing, but some of the data that Savoca et al. used to support their
claim are questionable, resulting in a misclassification of species, as well as other decisions regarding the variables
to include in their models. Furthermore, with their focus on a single lifestyle trait (nesting habit) of dubious
relevance for explaining plastic ingestion, Savoca et al. neglect the opportunity to explore other factors that
might provide better ecological insight. Finally, we are deeply concerned by the conservation policy recommendation
proposed by Savoca et al.âto increase antifouling properties of consumer plasticsâwhich constitutes a
substantial environmental risk and delivers the wrong message to decision-makers. The reduction of plastic consumption,
waste prevention, and proactive reuse through a circular economy should be at the heart of policy
recommendations for future mitigation efforts.info:eu-repo/semantics/publishedVersio
Ice Algae-Produced Carbon Is Critical for Overwintering of Antarctic Krill Euphausia superba
Antarctic krill Euphausia superba (âkrillâ) constitute a fundamental food source for Antarctic seabirds and mammals, and a globally important fisheries resource. The future resilience of krill to climate change depends critically on the winter survival of young krill. To survive periods of extremely low production by pelagic algae during winter, krill are assumed to rely partly on carbon produced by ice algae. The true dependency on ice algae-produced carbon, however, is so far unquantified. This confounds predictions on the future resilience of krill stocks to sea ice decline. Fatty acid (FA) analysis, bulk stable isotope analysis (BSIA), and compound-specific stable isotope analysis (CSIA) of diatom- and dinoflagellate-associated marker FAs were applied to quantify the dependency of overwintering larval, juvenile, and adult krill on ice algae-produced carbon (ÎąIce) during winter 2013 in the Weddell-Scotia Confluence Zone. Our results demonstrate that the majority of the carbon uptake of the overwintering larval and juvenile krill originated from ice algae (up to 88% of the carbon budget), and that the dependency on ice algal carbon decreased with ontogeny, reaching <56% of the carbon budget in adults. Spatio-temporal variability in the utilization of ice algal carbon was more pronounced in larvae and juvenile krill than in adults. Differences between ÎąIce estimates derived from short- vs. long-term FA-specific isotopic compositions suggested that ice algae-produced carbon gained importance as the winter progressed, and might become critical at the late winter-spring transition, before the phytoplankton bloom commences. Where the sea ice season shortens, reduced availability of ice algae might possibly not be compensated by surplus phytoplankton production during wintertime. Hence, sea ice decline could seriously endanger the winter survival of recruits, and subsequently overall biomass of krill
Sea-ice habitat minimizes grazing impact and predation risk for larval Antarctic krill
Survival of larval Antarctic krill (Euphausia superba) during winter is largely dependent upon the presence of sea ice as it provides an important source of food and shelter. We hypothesized that sea ice provides additional benefits because it hosts fewer competitors and provides reduced predation risk for krill larvae than the water column. To test our hypothesis, zooplankton were sampled in the Weddell-Scotia Confluence Zone at the ice-water interface (0â2 m) and in the water column (0â500 m) during AugustâOctober 2013. Grazing by mesozooplankton, expressed as a percentage of the phytoplankton standing stock, was higher in the water column (1.97âÂąâ1.84%) than at the ice-water interface (0.08âÂąâ0.09%), due to a high abundance of pelagic copepods. Predation risk by carnivorous macrozooplankton, expressed as a percentage of the mesozooplankton standing stock, was significantly lower at the ice-water interface (0.83âÂąâ0.57%; main predators amphipods, siphonophores and ctenophores) than in the water column (4.72âÂąâ5.85%; main predators chaetognaths and medusae). These results emphasize the important role of sea ice as a suitable winter habitat for larval krill with fewer competitors and lower predation risk. These benefits should be taken into account when considering the response of Antarctic krill to projected declines in sea ice. Whether reduced sea-ice algal production may be compensated for by increased water column production remains unclear, but the shelter provided by sea ice would be significantly reduced or disappear, thus increasing the predation risk on krill larvae
Monitoring of a Southern Giant Petrel Macronectes giganteus population on the Frazier Islands, Wilkes Land, Antarctica
Abstract Since 1956, Southern Giant Petrels on the Frazier Islands, East Antarctica, have been counted with different census techniques, sometimes varying within seasons and among islands, which hindered analysis of the data. Protective measures for the islands from 1986 onwards have increased the need for reliable long-term census data, but reduced the ways to collect these data. Published and unpublished data were re-examined, and population trends were reconstructed based on two relatively standardised techniques: the number of active chicks (AC) and the number of apparently occupied nests (AON) around hatching. AC-values from Nelly Island from 1959 to 1998 indicate substantial periodic fluctuations, but no consistent long-term change. Since the late 1970s, AC-values on the other two islands and AON-values suggest that the breeding population may have grown by 35%. This recent growth, however, is within the extent of periodic fluctuations observed in Southern Giant Petrel population that is stable over the long term
Recommended best practices for plastic and litter ingestion studies in marine birds: Collection, processing, and reporting
doi: 10.1139/facets-2018-0043Marine plastic pollution is an environmental contaminant of significant concern. There is a lack of
consistency in sample collection and processing that continues to impede meta-analyses and largescale comparisons across time and space. This is true for most taxa, including seabirds, which are
the most studied megafauna group with regards to plastic ingestion research. Consequently, it is difficult to evaluate the impacts and extent of plastic contamination in seabirds fully and accurately,
and to make inferences about species for which we have little or no data. We provide a synthesized set of recommendations specific for seabirds and plastic ingestion studies that include best practices in relation to sample collection, processing, and reporting, as well as highlighting some
âcross-cuttingâ methods. We include guidance for how carcasses, regurgitations, and pellets should
be handled and treated to prevent cross-contamination, and a discussion of what size class of microplastics can be assessed in each sample type. Although we focus on marine bird samples, we also
include standardized techniques to remove sediment and biological material that are generalizable
to other taxa. Lastly, metrics and data presentation of ingested plastics are briefly reviewed in the
context of seabird studies.Copyright: Š 2019 Provencher et al. This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. The attached file is the published pdf
Marine Strategy Framework Directive - Task Group 10 Report Marine Litter
The Marine Strategy Framework Directive (2008/56/EC) (MSFD) requires that the European Commis-sion (by 15 July 2010) should lay down criteria and methodological standards to allow consistency in approach in evaluating the extent to which Good Environmental Status (GES) is being achieved. ICES and JRC were contracted to provide scientific support for the Commission in meeting this obligation.
A total of 10 reports have been prepared relating to the descriptors of GES listed in Annex I of the Directive. Eight reports have been prepared by groups of independent experts coordinated by JRC and ICES in response to this contract. In addition, reports for two descriptors (Contaminants in fish and other seafood and Marine Litter) were written by expert groups coordinated by DG SANCO and IFREMER respectively.
A Task Group was established for each of the qualitative Descriptors. Each Task Group consisted of selected experts providing experience related to the four marine regions (the Baltic Sea, the North-east Atlantic, the Mediterranean Sea and the Black Sea) and an appropriate scope of relevant scien-tific expertise. Observers from the Regional Seas Conventions were also invited to each Task Group to help ensure the inclusion of relevant work by those Conventions. This is the report of Task Group 10 Marine litter.JRC.DDG.H.5-Rural, water and ecosystem resource
The Association of Antarctic Krill Euphausia superba with the Under-Ice Habitat
The association of Antarctic krill Euphausia superba with the under-ice habitat was investigated in the Lazarev Sea (Southern Ocean) during austral summer, autumn and winter. Data were obtained using novel Surface and Under Ice Trawls (SUIT), which sampled the 0â2 m surface layer both under sea ice and in open water. Average surface layer densities ranged between 0.8 individuals mâ2 in summer and autumn, and 2.7 individuals mâ2 in winter. In summer, under-ice densities of Antarctic krill were significantly higher than in open waters. In autumn, the opposite pattern was observed. Under winter sea ice, densities were often low, but repeatedly far exceeded summer and autumn maxima. Statistical models showed that during summer high densities of Antarctic krill in the 0â2 m layer were associated with high ice coverage and shallow mixed layer depths, among other factors. In autumn and winter, density was related to hydrographical parameters. Average under-ice densities from the 0â2 m layer were higher than corresponding values from the 0â200 m layer collected with Rectangular Midwater Trawls (RMT) in summer. In winter, under-ice densities far surpassed maximum 0â200 m densities on several occasions. This indicates that the importance of the ice-water interface layer may be under-estimated by the pelagic nets and sonars commonly used to estimate the population size of Antarctic krill for management purposes, due to their limited ability to sample this habitat. Our results provide evidence for an almost year-round association of Antarctic krill with the under-ice habitat, hundreds of kilometres into the ice-covered area of the Lazarev Sea. Local concentrations of postlarval Antarctic krill under winter sea ice suggest that sea ice biota are important for their winter survival. These findings emphasise the susceptibility of an ecological key species to changing sea ice habitats, suggesting potential ramifications on Antarctic ecosystems induced by climate change
Guidance on Monitoring of Marine Litter in European Seas
This publication is a Reference Report by the Joint Research Centre of the European Commission.The MSFD Technical Subgroup on Marine Litter was tasked to deliver guidance so that European Member States could
initiate programmes for monitoring of Descriptor 10 of the MSFD. The present document provides the recommendations
and information needed to commence the monitoring required for marine litter, including methodological protocols and
categories of items to be used for the assessment of litter on the Beach, Water Column, Seafloor and Biota, including a
special section on Microparticles
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