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Your search keyword '"Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI)"' showing total 3 results
Start Over Author "Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI)" Topic 0106 biological sciences
3 results on '"Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI)"'

1. A test of positive association for detecting heterogeneity in capture for capture-recapture data

Author

Thomas Bregnballe, Anita Jeyam, Roger Pradel, Rachel S. McCrea, Morten Frederiksen, Aarhus University [Aarhus], Department of Arctic Environment [Rockilde], Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), National Environmental Research Institute [Danmark] (NERI)-Aarhus University [Aarhus], Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud])

Subjects
0106 biological sciences, Statistics and Probability, Computer science, Goodness-of-fit, 010603 evolutionary biology, 01 natural sciences, Article, Mark and recapture, 010104 statistics & probability, Goodness of fit, Statistics, Econometrics, Thalasseus sandvicensis, QA276, Goodman–Kruskal’s gamma, 0101 mathematics, Cormack–Jolly–Seber model, Association (psychology), ComputingMilieux_MISCELLANEOUS, General Environmental Science, Applied Mathematics, Sampling (statistics), Diagnostic test, Agricultural and Biological Sciences (miscellaneous), Outcome (probability), Test (assessment), Statistics, Probability and Uncertainty, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, General Agricultural and Biological Sciences
Abstract

The Cormack–Jolly–Seber (CJS) model assumes that all marked animals have equal recapture probabilities at each sampling occasion, but heterogeneity in capture often occurs and should be taken into account to avoid biases in parameter estimates. Although diagnostic tests are generally used to detect trap-dependence or transience and assess the overall fit of the model, heterogeneity in capture is not routinely tested for. In order to detect and identify this phenomenon in a CJS framework, we propose a test of positive association between previous and future encounters using Goodman–Kruskal’s gamma. This test is based solely on the raw capture histories and makes no assumption on model structure. The development of the test is motivated by a dataset of Sandwich terns (Thalasseus sandvicensis), and we use the test to formally show that they exhibit heterogeneity in capture. We use simulation to assess the performance of the test in the detection of heterogeneity in capture, compared to existing and corrected diagnostic goodness-of-fit tests, Leslie’s test of equal catchability and Carothers’ extension of the Leslie test. The test of positive association is easy to use and produces good results, demonstrating high power to detect heterogeneity in capture. We recommend using this new test prior to model fitting as the outcome will guide the model-building process and help draw more accurate biological conclusions. Supplementary materials accompanying this paper appear online. Electronic Supplementary Material Supplementary materials for this article are available at 10.1007/s13253-017-0315-4.

Published
2018
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2. Temporal trend of mercury in polar bears (Ursus maritimus) from Svalbard using teeth as a biomonitoring tissue

Author

Christian Sonne, Øystein Wiig, Aurore Aubail, Rune Dietz, Frank Rigét, Florence Caurant, LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), National Environmental Research Institute (NERI), Department of Arctic Environment [Rockilde], Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI), Natural History Museum [Oslo], and University of Oslo (UiO)

Subjects
0106 biological sciences, Pollution, Male, Ursus maritimus, temporal trend, media_common.quotation_subject, chemistry.chemical_element, 010501 environmental sciences, Management, Monitoring, Policy and Law, 01 natural sciences, nitrogen, Svalbard, Dry weight, biology.animal, Biomonitoring, stable isotope, Animals, tooth, 0105 earth and related environmental sciences, media_common, polar bear, biology, Chemistry, Stable isotope ratio, 010604 marine biology & hydrobiology, carbon, Public Health, Environmental and Occupational Health, General Medicine, Mercury, Nitrogen, Hg, Mercury (element), 13. Climate action, Environmental chemistry, Polar, Environmental Pollutants, Female, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, Environmental Pollution, Ursidae, Environmental Monitoring
Abstract

International audience; We examined the use of mercury (Hg) and nitrogen and carbon stable isotopes in teeth of polar bear (Ursus maritimus) from Svalbard as biotracers of temporal changes in Hg pollution exposure between 1964 and 2003. Teeth were regarded as a good matrix of the Hg exposure, and in total 87 teeth of polar bears were analysed. Dental Hg levels ranged from 0.6 to 72.3 ng/g dry weight and increased with age the first 10 years of life. A decreasing time trend in Hg concentrations was observed over the recent four decades while no temporal changes were found in the stable isotope ratios of nitrogen (δ15N) and carbon (δ13C). This suggests that the decrease of Hg concentrations over time was more likely due to a lower environmental Hg exposure in this region rather than a shift in the feeding habits of Svalbard polar bears.

Published
2012
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3. Estimating prey capture rates of a planktivorous seabird, the little auk (Alle alle), using diet, diving behaviour, and energy consumption

Author

Ann M. A. Harding, Stéphane Blanc, Carsten Egevang, David Grémillet, Wojciech Walkusz, Flemming Merkel, Environmental Science Department, Alaska Pacific University, Greenland Institute for Natural Resources (GINR), Institute of Oceanology, Polska Akademia Nauk (PAN), Department of Arctic Environment [Rockilde], National Environmental Research Institute [Danmark] (NERI)-Aarhus University [Aarhus], Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Institute of Oceanology, Polish Academy of Sciences (IO-PAN), Polska Akademia Nauk = Polish Academy of Sciences (PAN), Aarhus University [Aarhus]-National Environmental Research Institute [Danmark] (NERI), Institut Pluridisciplinaire Hubert Curien (IPHC), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud])

Subjects
0106 biological sciences, Environmental change, Foraging, Greenland, Prey capture, 010603 evolutionary biology, 01 natural sciences, Zooplankton, Predation, biology.animal, Dovekie, 14. Life underwater, Underwater, biology, Ecology, 010604 marine biology & hydrobiology, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], biology.organism_classification, Time–depth-recorders, Calanus, Seabird, Doubly labelled water, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, General Agricultural and Biological Sciences, Foraging behaviour
Abstract

International audience; Abstract Interpreting the impact of environmental change on food webs requires a clear understanding of predator–prey interactions. Such knowledge is often lacking in the marine environment where the foraging behaviour and prey requirements of some of the major top-predators remains mysterious. For example, very little is known about the underwater foraging behaviour of the little auk, the most numerous seabird in the North Atlantic. In 2004, we used time–depth-recorders at two breeding colonies in East Greenland to examine the diving behaviour of this small, planktivorous seabird during the chick-rearing period. Due to technical difficulties data were only collected for four individuals, but recordings showed that birds dive up to 240 times a day to maximum depths of 27 m (average 10 m), with maximum dive durations of 90 s (average 52 s). In addition, we collected the chick meals from 35 individuals, which were dominated by Calanus copepods (95%), and also determined the field metabolic rates (FMR) of 14 individuals using the doubly labelled water technique, which averaged 609.9 kJ day-1. We integrated information on diving duration with chick diet and FMR to estimate the prey requirements and underwater capture rates of little auks using a Monte Carlo simulation. Chick-rearing little auks needed to catch about 59,800 copepods day-1, which is equivalent to about six copepods caught per second spent underwater. These astonishing results strongly suggest that little auks are, at least partly, filter-feeding, and underline the importance of highly productive, cool marine areas that harbour dense patches of large, energy-rich copepods.

Published
2009
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