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Petra Quillfeldt, Henri Weimerskirch, Karine Delord, Yves Cherel. (2020). Niche switching and leapfrog foraging: movement ecology of sympatric petrels during the early breeding season (Vol. 8).
Abstract: The timing of events in the early part of the breeding season is crucially important for successful reproduction. Long-lived animals that migrate large distances independently of each other meet at the breeding sites to re-establish their pair bonds and coordinate their breeding duties with their partners.
Keywords: Breeding schedule Central-place forager Foraging ecology Tracking
Programme: 109
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Hassen Allegue, Denis Réale, Baptiste Picard, Christophe Guinet. (2023). Track and dive-based movement metrics do not predict the number of prey encountered by a marine predator (Vol. 11). Bachelor's thesis, , .
Abstract: Studying animal movement in the context of the optimal foraging theory has led to the development of simple movement metrics for inferring feeding activity. Yet, the predictive capacity of these metrics in natural environments has been given little attention, raising serious questions of the validity of these metrics. The aim of this study is to test whether simple continuous movement metrics predict feeding intensity in a marine predator, the southern elephant seal (SES; Mirounga leonine), and investigate potential factors influencing the predictive capacity of these metrics.
Keywords: Accelerometry Area-restricted search Diving behavior Foraging behavior Marine predator Prey encounter events
Programme: 109,1201
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Thierry Anne-Mathilde, Ropert-Coudert Yan, Raclot Thierry, . (2013). Elevated corticosterone levels decrease reproductive output of chick-rearing Adélie penguins but do not affect chick mass at fledging
. Conservation Physiology, 1(1).
Abstract: Study of physiological mechanisms can help us to understand how animals respond to changing environmental conditions. In particular, stress hormones (i.e. glucocorticoids, such as corticosterone) are described as mediating resource allocation, allowing animals to adjust their physiology and behaviour to predictable and unpredictable changes in the environment. In this study, we investigated the effects of an experimental increase in baseline corticosterone levels on the breeding effort and the reproductive output of chick-rearing male Adélie penguins (Pygoscelis adeliae). The number of chicks per nest, their body mass, and their size were monitored throughout the study. Direct observations allowed measurement of the time spent foraging at sea and caring for the young on the nest. At the end of the treatment, blood samples were collected for isotope analysis. Although all birds raised at least one chick, reproductive output was decreased by 42% in corticosterone-treated birds compared with control birds. The increase in corticosterone levels during the guard stage did not affect the mass of surviving chicks or the brood mass at fledging. Corticosterone-treated males spent on average 21% more time at the nest than control birds. However, the duration of foraging trips was similar between both groups. In addition, the similarity of isotopic signatures suggests that both groups foraged at similar locations and ingested the same prey species. The detailed on-land behaviour of birds should be examined in further studies to clarify the possible links between corticosterone levels, brooding time, and reproductive output. Understanding the relationships between glucocorticoids, fitness, and ultimately population dynamics is fundamental to enabling conservation physiology as a discipline to be successful in helping to manage species of conservation concern.
Keywords: Breeding effort, glucocorticoids, Pygoscelis adeliae, reproductive output, Seabird,
Programme: 1091
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Meyer X, MacIntosh AJJ, Kato A, Chiaradia A, Ropert-Coudert Y. (2015). Hydrodynamic handicaps and organizational complexity in the foraging behavior of two free-ranging penguin species. Animal Biotelemetry, 3, 25.
Abstract: Animal movement exhibits self-similarity across a range of both spatial and temporal scales reminiscent of statistical fractals. Stressors are known to induce changes in these statistical patterns of behavior, although the direction and interpretation of such changes are not always clear. We examined whether the imposition of known hydrodynamic disruptors, bio-logging devices and flipper bands, induces changes in the temporal organization (complexity) of foraging sequences in two penguin species, little penguins (Eudyptula minor) and Adélie penguins (Pygoscelis adeliae). Detrended fluctuation analysis showed that foraging sequences produced by little penguins carrying larger loggers were more complex, i.e., were more erratic tending toward greater stochasticity, than those carrying smaller loggers. However, logger size did not affect complexity in foraging sequences of Adélie penguins. Logger position was associated only weakly with altered complexity in little penguins, with individuals carrying loggers in the middle of their backs displaying slightly more complex dive sequences than those carrying loggers lower on their backs. Finally, despite their known negative effects on penguin fitness, flipper bands were not associated with dive sequence complexity in little penguins. Despite that externally attached devices can disrupt certain behavioral parameters in diving seabirds, we found mixed evidence in support of the hypothesis that such devices significantly disrupt the time-structured organizational properties of foraging sequences in the two penguin species investigated. However, smaller species carrying larger loggers, and perhaps those positioned higher on their backs, may experience an added element of noise in their behavioral sequences that may indicate a departure from foraging behavior observed under normal, unburdened conditions.
Programme: 1091
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Heerah Karine, Hindell Mark, Guinet Christophe, Charrassin Jean‑Benoît. (2015). From high-resolution to low-resolution dive datasets: a new index to quantify the foraging effort of marine predators. Animal Biotelemetry, 3, 42.
Abstract: In the last decade, thousands of satellite-relayed data loggers (SRDLs) have been deployed, providing large datasets on marine predator movement patterns at sea and their diving behaviour. However, the latter is in a highly summarised, low-resolution form, from which it is difficult to make the sorts of important behavioural inferences that are possible from higher-resolution datasets (such as detection of likely foraging events). The main objective of this study was to develop a simple, but accurate tool to detect and quantify within-dive foraging periods in low-resolution dives.
Programme: 109
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Scott A. Shaffer, Pierre Blévin, Christophe Barbraud, Olivier Chastel, Henri Weimerskirch. (2021). Comparative egg attendance patterns of incubating polar petrels (Vol. 9).
Abstract: The internal environment of eggs in most birds is regulated by transferring heat energy through contact incubation, maintaining nest microclimate, and frequent egg turning by the incubating parent on its nest. However, we lack information about egg attendance patterns in birds that breed in polar environments where variations in life history are expected to influence incubation behavior. Moreover, crevice/burrow nesting petrels in high-latitude regions are known for periodically leaving their egg unattended (hereafter ‘egg neglect’), but there is little reporting on the internal condition of unattended eggs. At Dumont d’Urville Station, Antarctica, we studied the incubation behavior of 24 snow (Pagodroma nivea) and 15 Cape (Daption capense) petrel pairs using egg loggers that recorded egg turning rates, orientation changes, and temperatures at 1 Hz for durations of 3–6 days.
Keywords: Biologging Cape petrel Egg neglect Egg temperatures Egg turning rates Snow petrel
Programme: 109
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P. L. Woodworth, J. R. Hunter, M. Marcos, P. Caldwell, M. Menéndez, I. Haigh. (2016). Towards a global higher-frequency sea level dataset (Vol. 3).
Abstract: This paper describes the assembly of an updated quasi-global dataset of higher-frequency sea level information obtained from tide gauges operated by many agencies around the world. We believe that the construction of such a dataset is fundamental to scientific research in sea level variability and also to practical aspects of coastal engineering. A first version of the dataset was used in approximately a dozen published studies, and this second version is about twice the size, containing longer and more geographically representative sea level records. The dataset has acquired a digital object identifier and may be obtained from several sources. The paper mentions some of the merits of and deficiencies with the present version and takes a forward look at how the dataset may be updated in the future.
Keywords: international data centres sea level data tide gauges
Programme: 688
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Ivan D. Haigh, Marta Marcos, Stefan A. Talke, Philip L. Woodworth, John R. Hunter, Ben S. Hague, Arne Arns, Elizabeth Bradshaw, Philip Thompson. (2022). GESLA Version 3: A major update to the global higher-frequency sea-level dataset (Vol. 10).
Abstract: This paper describes a major update to the quasi-global, higher-frequency sea-level dataset known as GESLA (Global Extreme Sea Level Analysis). Versions 1 (released 2009) and 2 (released 2016) of the dataset have been used in many published studies, across a wide range of oceanographic and coastal engineering-related investigations concerned with evaluating tides, storm surges, extreme sea levels, and other related processes. The third version of the dataset (released 2021), presented here, contains double the number of years of data, and nearly four times the number of records, compared to Version 2. The dataset consists of records obtained from multiple sources around the world. This paper describes the assembly of the dataset, its processing, and its format, and outlines potential future improvements.
Keywords: sea level records sea level rise storm surges storm tides tide gauge
Programme: 688
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Gaia Piccioni, Denise Dettmering, Wolfgang Bosch, Florian Seitz. (2019). TICON: TIdal CONstants based on GESLA sea-level records from globally located tide gauges (Vol. 6).
Abstract: The TICON (TIdal CONstants) dataset contains harmonic constants of 40 tidal constituents computed for 1,145 tide gauges distributed globally. The tidal estimations are based on publicly available sea level records of the second version of the Global Extreme Sea Level Analysis (GESLA) project and were derived through a least squares-based harmonic analysis on the single time series. A preliminary screening was performed on all records to exclude doubtful observations. Only the records containing more than 70% of valid measurements were processed, that correspond to 89.7% of the total 1,276 original public GESLA records. The results are stored in a text file, and include additional information on the position of the stations, the starting and ending years of the analysed record, the estimated error of the fit, a code that corresponds to the source of the record and additional information on the single time series. In ocean tide models, data from in situ stations are used for validation purposes, and TICON is a useful and easy-to-handle data set that allows the users to select the records according to different criteria most suitable for their purposes. The data are provided with DOI identification in the PANGAEA repository.
Keywords: GESLA tide gauge tides
Programme: 688
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Juan José Curto, Antoni Segarra, David Altadill, Aude Chambodut. (2023). Service of rapid magnetic variations, an update (Vol. 10).
Abstract: Rapid magnetic variations on Earth are intimately linked with solar activity and this is one of the main topics in Space Weather research. Modelling and forecasting these phenomena are vital in our technological society. The Service of Rapid Magnetic Variations provides lists of these remarkable magnetic events in a continuous way in what constitutes a long geophysical series that began in the late 19th century. Although the aim of this Service remains unchanged, methods have changed with time. Here, we describe the recent evolution of the Service, its database and the latest works carried out to improve the products delivered to the scientific society.
Keywords: event detection ISGI – International Service of Geomagnetic Indices rapid magnetic variations solar flare effects storm sudden commencements
Programme: 139
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