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1. Tri-axial accelerometry allows to determine parental food provisioning behaviour in a marine bird

Author

Monserrat Del Caño, Flavio Quintana, Giacomo Dell’Omo, and Agustina Gómez-Laich

Subjects
Accelerometry, Food provisioning, Imperial shag, Leucocarbo atriceps, Seabird, Support vector machine, Zoology, QL1-991
Abstract

The study of parental food provisioning is essential for understanding the breeding ecology of birds. We conducted the first study using accelerometry to detect food provisioning in birds, using Support Vector Machine (SVM) models to identify when adults feed chicks of three different age classes. Accelerometers were attached to the head of adult female Imperial Shags (Leucocarbo atriceps), and various attributes derived from the acceleration signals were used to train SVM models for each chick age class. Model performance improved with chick age class, with SVM models achieving high overall accuracy (>88%) and highest sensitivity in older chick categories (>91%). However, precision values, especially for younger chicks, remained relatively low (between 26% and 45%). The application of a time filter based on the minimum duration of the observed food provisioning behaviours for each chick age category, improved model performance by reducing false provisioning behaviours, particularly in the model for older chicks, which showed the highest precision (72.4%). This study highlights the effectiveness of accelerometry and machine learning in studying parental food provisioning in birds, providing a rapid and accurate data collection method to complement traditional techniques. The described methodology can be applied to any bird species that exhibits distinctive movements while feeding its offspring and has suitable characteristics for attaching an accelerometer to the body part that best captures this movement. Finally, it is hoped that the results of this study will contribute to future research on key questions in parental investment theory and reproductive strategies in birds.

Published
2024
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2. How often should dead-reckoned animal movement paths be corrected for drift?

Author

Richard M. Gunner, Mark D. Holton, David M. Scantlebury, Phil Hopkins, Emily L. C. Shepard, Adam J. Fell, Baptiste Garde, Flavio Quintana, Agustina Gómez-Laich, Ken Yoda, Takashi Yamamoto, Holly English, Sam Ferreira, Danny Govender, Pauli Viljoen, Angela Bruns, O. Louis van Schalkwyk, Nik C. Cole, Vikash Tatayah, Luca Börger, James Redcliffe, Stephen H. Bell, Nikki J. Marks, Nigel C. Bennett, Mariano H. Tonini, Hannah J. Williams, Carlos M. Duarte, Martin C. van Rooyen, Mads F. Bertelsen, Craig J. Tambling, and Rory P. Wilson

Subjects
Biologging, Dead-reckoning, Drift, Global Positioning System (GPS), Animal movement, Animal tracking, Ecology, QH540-549.5, Animal biochemistry, QP501-801
Abstract

Abstract Background Understanding what animals do in time and space is important for a range of ecological questions, however accurate estimates of how animals use space is challenging. Within the use of animal-attached tags, radio telemetry (including the Global Positioning System, ‘GPS’) is typically used to verify an animal’s location periodically. Straight lines are typically drawn between these ‘Verified Positions’ (‘VPs’) so the interpolation of space-use is limited by the temporal and spatial resolution of the system’s measurement. As such, parameters such as route-taken and distance travelled can be poorly represented when using VP systems alone. Dead-reckoning has been suggested as a technique to improve the accuracy and resolution of reconstructed movement paths, whilst maximising battery life of VP systems. This typically involves deriving travel vectors from motion sensor systems and periodically correcting path dimensions for drift with simultaneously deployed VP systems. How often paths should be corrected for drift, however, has remained unclear. Methods and results Here, we review the utility of dead-reckoning across four contrasting model species using different forms of locomotion (the African lion Panthera leo, the red-tailed tropicbird Phaethon rubricauda, the Magellanic penguin Spheniscus magellanicus, and the imperial cormorant Leucocarbo atriceps). Simulations were performed to examine the extent of dead-reckoning error, relative to VPs, as a function of Verified Position correction (VP correction) rate and the effect of this on estimates of distance moved. Dead-reckoning error was greatest for animals travelling within air and water. We demonstrate how sources of measurement error can arise within VP-corrected dead-reckoned tracks and propose advancements to this procedure to maximise dead-reckoning accuracy. Conclusions We review the utility of VP-corrected dead-reckoning according to movement type and consider a range of ecological questions that would benefit from dead-reckoning, primarily concerning animal–barrier interactions and foraging strategies.

Published
2021
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3. Dead-reckoning animal movements in R: a reappraisal using Gundog.Tracks

Author

Richard M. Gunner, Mark D. Holton, Mike D. Scantlebury, O. Louis van Schalkwyk, Holly M. English, Hannah J. Williams, Phil Hopkins, Flavio Quintana, Agustina Gómez-Laich, Luca Börger, James Redcliffe, Ken Yoda, Takashi Yamamoto, Sam Ferreira, Danny Govender, Pauli Viljoen, Angela Bruns, Stephen H. Bell, Nikki J. Marks, Nigel C. Bennett, Mariano H. Tonini, Carlos M. Duarte, Martin C. van Rooyen, Mads F. Bertelsen, Craig J. Tambling, and Rory P. Wilson

Subjects
Animal behaviour, Animal movement, Global Positioning System, R (programming language), Track integration, Tri-axial accelerometers, Ecology, QH540-549.5, Animal biochemistry, QP501-801
Abstract

Abstract Background Fine-scale data on animal position are increasingly enabling us to understand the details of animal movement ecology and dead-reckoning, a technique integrating motion sensor-derived information on heading and speed, can be used to reconstruct fine-scale movement paths at sub-second resolution, irrespective of the environment. On its own however, the dead-reckoning process is prone to cumulative errors, so that position estimates quickly become uncoupled from true location. Periodic ground-truthing with aligned location data (e.g., from global positioning technology) can correct for this drift between Verified Positions (VPs). We present step-by-step instructions for implementing Verified Position Correction (VPC) dead-reckoning in R using the tilt-compensated compass method, accompanied by the mathematical protocols underlying the code and improvements and extensions of this technique to reduce the trade-off between VPC rate and dead-reckoning accuracy. These protocols are all built into a user-friendly, fully annotated VPC dead-reckoning R function; Gundog.Tracks, with multi-functionality to reconstruct animal movement paths across terrestrial, aquatic, and aerial systems, provided within the Additional file 4 as well as online (GitHub). Results The Gundog.Tracks function is demonstrated on three contrasting model species (the African lion Panthera leo, the Magellanic penguin Spheniscus magellanicus, and the Imperial cormorant Leucocarbo atriceps) moving on land, in water and in air. We show the effect of uncorrected errors in speed estimations, heading inaccuracies and infrequent VPC rate and demonstrate how these issues can be addressed. Conclusions The function provided will allow anyone familiar with R to dead-reckon animal tracks readily and accurately, as the key complex issues are dealt with by Gundog.Tracks. This will help the community to consider and implement a valuable, but often overlooked method of reconstructing high-resolution animal movement paths across diverse species and systems without requiring a bespoke application.

Published
2021
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4. Options for modulating intra-specific competition in colonial pinnipeds: the case of harbour seals (Phoca vitulina) in the Wadden Sea

Author

Rory P. Wilson, Nikolai Liebsch, Agustina Gómez-Laich, William P. Kay, Andrew Bone, Victoria J. Hobson, and Ursula Siebert

Subjects
Pinniped, Dive behaviour, Sexual segregation, Dive duration, Swim speed, Harbour seal, Medicine, Biology (General), QH301-705.5
Abstract

Colonial pinnipeds may be subject to substantial consumptive competition because they are large, slow-moving central place foragers. We examined possible mechanisms for reducing this competition by examining the diving behaviour of harbour seals (Phoca vitulina) after equipping 34 seals (11 females, 23 males) foraging from three locations; Rømø, Denmark and Lorenzenplate and Helgoland, Germany, in the Wadden Sea area with time-depth recorders. Analysis of 319,021 dives revealed little between-colony variation but appreciable inter-sex differences, with males diving deeper than females, but for shorter periods. Males also had higher vertical descent rates. This result suggests that males may have higher overall swim speeds, which would increase higher oxygen consumption, and may explain the shorter dive durations compared to females. Intersex variation in swim speed alone is predicted to lead to fundamental differences in the time use of three-dimensional space, which may help reduce consumptive competition in harbour seals and other colonial pinnipeds.

Published
2015
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5. Selfies of Imperial Cormorants (Phalacrocorax atriceps): What Is Happening Underwater?

Author

Agustina Gómez-Laich, Ken Yoda, Carlos Zavalaga, and Flavio Quintana

Subjects
Medicine, Science
Abstract

During the last few years, the development of animal-borne still cameras and video recorders has enabled researchers to observe what a wild animal sees in the field. In the present study, we deployed miniaturized video recorders to investigate the underwater foraging behavior of Imperial cormorants (Phalacrocorax atriceps). Video footage was obtained from 12 animals and 49 dives comprising a total of 8.1 h of foraging data. Video information revealed that Imperial cormorants are almost exclusively benthic feeders. While foraging along the seafloor, animals did not necessarily keep their body horizontal but inclined it downwards. The head of the instrumented animal was always visible in the videos and in the majority of the dives it was moved constantly forward and backward by extending and contracting the neck while travelling on the seafloor. Animals detected prey at very short distances, performed quick capture attempts and spent the majority of their time on the seafloor searching for prey. Cormorants foraged at three different sea bottom habitats and the way in which they searched for food differed between habitats. Dives were frequently performed under low luminosity levels suggesting that cormorants would locate prey with other sensory systems in addition to sight. Our video data support the idea that Imperial cormorants' efficient hunting involves the use of specialized foraging techniques to compensate for their poor underwater vision.

Published
2015
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6. Love thy neighbour: automatic animal behavioural classification of acceleration data using the K-nearest neighbour algorithm.

Author

Owen R Bidder, Hamish A Campbell, Agustina Gómez-Laich, Patricia Urgé, James Walker, Yuzhi Cai, Lianli Gao, Flavio Quintana, and Rory P Wilson

Subjects
Medicine, Science
Abstract

Researchers hoping to elucidate the behaviour of species that aren't readily observed are able to do so using biotelemetry methods. Accelerometers in particular are proving particularly effective and have been used on terrestrial, aquatic and volant species with success. In the past, behavioural modes were detected in accelerometer data through manual inspection, but with developments in technology, modern accelerometers now record at frequencies that make this impractical. In light of this, some researchers have suggested the use of various machine learning approaches as a means to classify accelerometer data automatically. We feel uptake of this approach by the scientific community is inhibited for two reasons; 1) Most machine learning algorithms require selection of summary statistics which obscure the decision mechanisms by which classifications are arrived, and 2) they are difficult to implement without appreciable computational skill. We present a method which allows researchers to classify accelerometer data into behavioural classes automatically using a primitive machine learning algorithm, k-nearest neighbour (KNN). Raw acceleration data may be used in KNN without selection of summary statistics, and it is easily implemented using the freeware program R. The method is evaluated by detecting 5 behavioural modes in 8 species, with examples of quadrupedal, bipedal and volant species. Accuracy and Precision were found to be comparable with other, more complex methods. In order to assist in the application of this method, the script required to run KNN analysis in R is provided. We envisage that the KNN method may be coupled with methods for investigating animal position, such as GPS telemetry or dead-reckoning, in order to implement an integrated approach to movement ecology research.

Published
2014
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7. The role of wingbeat frequency and amplitude in flight power

Author

Krishnamoorthy Krishnan, Baptiste Garde, Ashley Bennison, Nik C. Cole, Emma-L. Cole, Jamie Darby, Kyle H. Elliott, Adam Fell, Agustina Gómez-Laich, Sophie de Grissac, Mark Jessopp, Emmanouil Lempidakis, Yuichi Mizutani, Aurélien Prudor, Michael Quetting, Flavio Quintana, Hermina Robotka, Alexandre Roulin, Peter G. Ryan, Kim Schalcher, Stefan Schoombie, Vikash Tatayah, Fred Tremblay, Henri Weimerskirch, Shannon Whelan, Martin Wikelski, Ken Yoda, Anders Hedenström, and Emily L. C. Shepard

Subjects
Biomaterials, Birds, ddc:570, Flight, Animal, Biomedical Engineering, Biophysics, Animals, Wings, Animal, Bioengineering, Biochemistry, Biotechnology, Biomechanical Phenomena
Abstract

Body-mounted accelerometers provide a new prospect for estimating power use in flying birds, as the signal varies with the two major kinematic determinants of aerodynamic power: wingbeat frequency and amplitude. Yet wingbeat frequency is sometimes used as a proxy for power output in isolation. There is, therefore, a need to understand which kinematic parameter birds vary and whether this is predicted by flight mode (e.g. accelerating, ascending/descending flight), speed or morphology. We investigate this using high-frequency acceleration data from (i) 14 species flying in the wild, (ii) two species flying in controlled conditions in a wind tunnel and (iii) a review of experimental and field studies. While wingbeat frequency and amplitude were positively correlated, R 2 values were generally low, supporting the idea that parameters can vary independently. Indeed, birds were more likely to modulate wingbeat amplitude for more energy-demanding flight modes, including climbing and take-off. Nonetheless, the striking variability, even within species and flight types, highlights the complexity of describing the kinematic relationships, which appear sensitive to both the biological and physical context. Notwithstanding this, acceleration metrics that incorporate both kinematic parameters should be more robust proxies for power than wingbeat frequency alone.

Published
2022

8. Long walk home: Magellanic penguins have strategies that lead them to areas where they can navigate most efficiently

Author

Flavio Quintana, Agustina Gómez-Laich, Richard M. Gunner, Fabián Gabelli, Giacomo Dell Omo, Carlos Duarte, Martín Brogger, and Rory P. Wilson

Subjects
General Immunology and Microbiology, Ecology, Bird Diseases, Animals, General Medicine, General Agricultural and Biological Sciences, Spheniscidae, General Biochemistry, Genetics and Molecular Biology, General Environmental Science
Abstract

Understanding how animals move in dense environments where vision is compromised is a major challenge. We used GPS and dead-reckoning to examine the movement of Magellanic penguins commuting through vegetation that precluded long-distance vision. Birds leaving the nest followed the shortest, quickest route to the sea (the ‘ideal path’, or ' I-path ') but return tracks depended where the birds left the water. Penguins arriving at the beach departure spot mirrored the departure. Most of those landing at a distance from the departure spot travelled slowly, obliquely to the coast at a more acute angle than a beeline trajectory to the nest. On crossing their I-path , these birds then followed this route quickly to their nests. This movement strategy saves birds distance, time and energy compared to a route along the beach and the into the colony on the I-track and saves time and energy compared to a beeline trajectory which necessitates slow travel in unfamiliar areas. This suggests that some animals adopt tactics that take them to an area where their navigational capacities are enhanced for efficient travel in challenging environments.

Published
2022

9. Optimizing the use of biologgers for movement ecology research

Author

Holly M. English, Juan M. Morales, Urška Demšar, Alice M. Trevail, Agustina Gómez-Laich, Rachael C Griffiths, Anouk Spelt, Rory P. Wilson, Thomas A. Clay, William P. Kay, Allert I. Bijleveld, Lucy A. Taylor, Christian Rutz, Luca Börger, Jonathan R. Potts, Katharine F Rogerson, Hannah J. Williams, Simon Benhamou, Sophie de Grissac, Novella Franconi, Department of Biosciences, Swansea University, University of Oxford [Oxford], Save the Elephants, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), 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 National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Royal Netherlands Institute for Sea Research (NIOZ), School of Environmental Sciences [Liverpool], University of Liverpool, University of St Andrews [Scotland], Instituto de Biología de Organismos Marinos [Chubut] (IBIOMAR), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Universidad Nacional del Comahue [Neuquén] (UNCOMA), Instituto Nacional de Investigaciones en Biodiversidad y Medioambiente [Bariloche] (INIBIOMA-CONICET), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Universidad Nacional del Comahue [Neuquén] (UNCOMA), School of Mathematics and Statistics [Sheffield] (SoMaS), University of Sheffield [Sheffield], School of Environmental and Life Sciences, University of East Anglia [Norwich] (UEA), Department of Aerospace Engineering [Bristol], University of Bristol [Bristol], University of Oxford, Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, 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), The Leverhulme Trust, University of St Andrews. School of Geography & Sustainable Development, University of St Andrews. Bell-Edwards Geographic Data Institute, University of St Andrews. Centre for Biological Diversity, University of St Andrews. Centre for Social Learning & Cognitive Evolution, and University of St Andrews. School of Biology

Subjects
0106 biological sciences, Matching (statistics), BIG DATA, Computer science, Biologging, QH301 Biology, Ecology (disciplines), Movement, GPS, Big data, NDAS, 010603 evolutionary biology, 01 natural sciences, Article, purl.org/becyt/ford/1 [https], Ciencias Biológicas, QH301, Data visualization, ACCELEROMETER, Multidisciplinary approach, MOVEMENT ECOLOGY, Multidimensional visualization, Animals, DATA VISUALIZATION, Set (psychology), purl.org/becyt/ford/1.6 [https], Ecology, Evolution, Behavior and Systematics, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Ecology, business.industry, 010604 marine biology & hydrobiology, INTEGRATED BIOLOGGING FRAMEWORK, Statistical model, Ecología, MULTIDISCIPLINARY COLLABORATION, 13. Climate action, Animal Science and Zoology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, business, CIENCIAS NATURALES Y EXACTAS, MULTISENSOR APPROACH
Abstract

The paradigm-changing opportunities of biologging sensors for ecological research, especially movement ecology, are vast, but the crucial questions of how best to match the most appropriate sensors and sensor combinations to specific biological questions and how to analyse complex biologging data, are mostly ignored. Here, we fill this gap by reviewing how to optimize the use of biologging techniques to answer questions in movement ecology and synthesize this into an Integrated Biologging Framework (IBF). We highlight that multisensor approaches are a new frontier in biologging, while identifying current limitations and avenues for future development in sensor technology. We focus on the importance of efficient data exploration, and more advanced multidimensional visualization methods, combined with appropriate archiving and sharing approaches, to tackle the big data issues presented by biologging. We also discuss the challenges and opportunities in matching the peculiarities of specific sensor data to the statistical models used, highlighting at the same time the large advances which will be required in the latter to properly analyse biologging data. Taking advantage of the biologging revolution will require a large improvement in the theoretical and mathematical foundations of movement ecology, to include the rich set of high-frequency multivariate data, which greatly expand the fundamentally limited and coarse data that could be collected using location-only technology such as GPS. Equally important will be the establishment of multidisciplinary collaborations to catalyse the opportunities offered by current and future biologging technology. If this is achieved, clear potential exists for developing a vastly improved mechanistic understanding of animal movements and their roles in ecological processes and for building realistic predictive models. Fil: Williams, Hannah J.. Swansea University; Reino Unido Fil: Taylor, Lucy. University of Oxford; Reino Unido. Save The Elephants; Kenia Fil: Benhamou, Simon. Centre National de la Recherche Scientifique; Francia Fil: Bijleveld, Allert. Utrecht University; Países Bajos Fil: Clay, Thomas. University of Liverpool; Reino Unido Fil: de Grissac, Sophie. Swansea University; Reino Unido Fil: Demsar, Urska. University of St. Andrews; Reino Unido Fil: English, Holly M.. Swansea University; Reino Unido Fil: Franconi, Novella. Swansea University; Reino Unido Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Griffiths, Rachael. Swansea University; Reino Unido Fil: Kay, William P.. Swansea University; Reino Unido Fil: Morales, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Potts, Jonathan. University of Sheffield; Reino Unido Fil: Rogerson, Katharine F.. University of East Anglia; Reino Unido Fil: Rutz, Christian. University of St. Andrews; Reino Unido Fil: Spelt, Anouk. University of Bristol; Reino Unido Fil: Trevail, Alice. University of Liverpool; Reino Unido Fil: Wilson, Rory P.. Swansea University; Reino Unido Fil: Börger, Luca. Swansea University; Reino Unido

Published
2020

10. Estimates for energy expenditure in free‐living animals using acceleration proxies; a reappraisal

Author

Nathan R. Geraldi, Agustina Gómez-Laich, Hannah J. Williams, Frank Rosell, Nikki J. Marks, Richard Gunner, Flavio Quintana, Patricia Maria Graf, Carlos M. Duarte, Rebecca Scott, Mark D. Holton, Emily L. C. Shepard, Hermina Robotka, Michael S. Strano, Lloyd W. Hopkins, Andreas Fahlman, Rory P. Wilson, Christophe Eizaguirre, D. Michael Scantlebury, and Luca Börger

Subjects
0106 biological sciences, Computer science, Movement, Acceleration, WILD ANIMALS, 010603 evolutionary biology, 01 natural sciences, Proxy (climate), Article, purl.org/becyt/ford/1 [https], Ciencias Biológicas, MOVEMENT COSTS, Econometrics, Animals, Total energy, purl.org/becyt/ford/1.6 [https], Ecology, Evolution, Behavior and Systematics, Metabolic power, DOUBLY LABELLED WATER, 010604 marine biology & hydrobiology, DYNAMIC BODY ACCELERATION, Zoología, Ornitología, Entomología, Etología, ENERGY EXPENDITURE, Energy expenditure, Metabolic rate, Animal Science and Zoology, Energy Metabolism, CIENCIAS NATURALES Y EXACTAS
Abstract

It is fundamentally important for many animal ecologists to quantify the costs of animal activities, although it is not straightforward to do so. The recording of triaxial acceleration by animal-attached devices has been proposed as a way forward for this, with the specific suggestion that dynamic body acceleration (DBA) be used as a proxy for movement-based power. Dynamic body acceleration has now been validated frequently, both in the laboratory and in the field, although the literature still shows that some aspects of DBA theory and practice are misunderstood. Here, we examine the theory behind DBA and employ modelling approaches to assess factors that affect the link between DBA and energy expenditure, from the deployment of the tag, through to the calibration of DBA with energy use in laboratory and field settings. Using data from a range of species and movement modes, we illustrate that vectorial and additive DBA metrics are proportional to each other. Either can be used as a proxy for energy and summed to estimate total energy expended over a given period, or divided by time to give a proxy for movement-related metabolic power. Nonetheless, we highlight how the ability of DBA to predict metabolic rate declines as the contribution of non-movement-related factors, such as heat production, increases. Overall, DBA seems to be a substantive proxy for movement-based power but consideration of other movement-related metrics, such as the static body acceleration and the rate of change of body pitch and roll, may enable researchers to refine movement-based metabolic costs, particularly in animals where movement is not characterized by marked changes in body acceleration. Fil: Wilson, Rory P.. Swansea University; Reino Unido Fil: Börger, Luca. Swansea University; Reino Unido Fil: Holton, Mark. Swansea University; Reino Unido Fil: Scantlebury, D. Michael. The Queens University of Belfast; Irlanda Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Rosell, Frank. University of South‐Eastern Norway; Noruega Fil: Graf, Patricia M.. Universitat Fur Bodenkultur Wien; Austria. University of Ljubljana; Eslovenia Fil: Williams, Hannah. Swansea University; Reino Unido Fil: Gunner, Richard. Swansea University; Reino Unido Fil: Hopkins, Lloyd. Swansea University; Reino Unido Fil: Marks, Nikki. The Queens University of Belfast; Irlanda Fil: Geraldi, Nathan R.. King Abdullah University of Science and Technology; Arabia Saudita Fil: Duarte, Carlos M.. King Abdullah University of Science and Technology; Arabia Saudita Fil: Scott, Rebecca. Geomar-Helmholtz Centre for Ocean Research Kiel; Alemania Fil: Strano, Michael S.. Massachusetts Institute of Technology; Estados Unidos Fil: Robotka, Hermina. Max Planck Institute für Ornithologie; Alemania Fil: Eizaguirre, Christophe. , Queen Mary University of London; Reino Unido Fil: Fahlman, Andreas. undación Oceanogràfic de la Comunidad Valenciana; España Fil: Shepard, Emily L. C.. Swansea University; Reino Unido. Max Planck Institute für Ornithologie; Alemania

Published
2020

11. The eldest sibling is the lousiest in an obligate brood reducer seabird

Author

Flavio Quintana, María Soledad Leonardi, Agustina Gómez Laich, and Walter S. Svagelj

Subjects
0106 biological sciences, SEABIRDS, TRANSMISSION, Otras Ciencias Biológicas, CHEWING LICE, Parasitism, 010603 evolutionary biology, 01 natural sciences, 010605 ornithology, Ciencias Biológicas, biology.animal, Sibling, HOST-PARASITE DYNAMIC, Ecology, Evolution, Behavior and Systematics, Nature and Landscape Conservation, biology, Obligate, Hatching, Ecology, Brood, Animal Science and Zoology, Conservation biology, Seabird, Ornithology, SHAG, CIENCIAS NATURALES Y EXACTAS
Abstract

Previous studies on vertical transmission of lice on terrestrial birds have shown that the intensity of parasitism can vary within broods in relation to the hatching order of chicks. In species where the hatching order has an important effect on chick survival, lice would benefit from living on the host with the highest survival prospects. In the present work, we test this hypothesis using as model lice from the Imperial Shag, an obligate brood reducer. Our specific aims were to investigate how infestation of Eidmanniella pellucida varies in relation to the age, the order of birth and the hatching date of chicks. We observed that chicks were infested by their parents during their first days of life, mainly by lice in nymphal stage. The first chick to hatch was the most infested. Infestation was also affected by hatching date, increasing as the season progressed, reaching a maximum at the peak of the breeding season and decreasing gradually after that. The age of the chick was unrelated to the intensity of infestation. Our results suggest that lice would prefer the chick that is more likely to survive and highlights the adaptive strategies of lice according to the ecology of their hosts. Fil: Leonardi, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Svagelj, Walter Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina

Published
2017

12. Jellyfish and other gelata as food for four penguin species – insights from predator-borne videos

Author

Akiko Kato, Timothée A. Poupart, Jean-Baptiste Thiebot, Thierry Raclot, Takuji Noda, Kentaro Ito, Akinori Takahashi, Philip J. Seddon, Hiromichi Mitamura, Grace J. Sutton, John P. Y. Arnould, Flavio Quintana, Juan E. Sala, Thomas Mattern, Agustina Gómez-Laich, Yan Ropert-Coudert, Ken Yoda, National Insitute of Polar Research [Japan], National Institute of Polar Research [Tokyo] (NiPR), School of Environmental and Life Sciences - SELS (Callaghan, Australia), University of Newcastle [Australia] (UoN), Instituto de Biología de Organismos Marinos [Chubut] (IBIOMAR), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Department of Polar Science, Graduate University for Advanced Sciences, Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Institut National de la Recherche Agronomique (INRA)-Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Department of Zoology, University of Otago [Dunedin, Nouvelle-Zélande], Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Ecological niche, Jellyfish, Ecology, 010604 marine biology & hydrobiology, Ecology (disciplines), Otras Ciencias Biológicas, Pelagic zone, Biology, 010603 evolutionary biology, 01 natural sciences, FORAGING BEHAVIOUR, Predation, JELLYFISH, Ciencias Biológicas, biology.animal, [SDE]Environmental Sciences, PENGUINS, VIEDEO CAMERAS, 14. Life underwater, Predator, Ecology, Evolution, Behavior and Systematics, CIENCIAS NATURALES Y EXACTAS, Trophic level
Abstract

Jellyfish and other pelagic gelatinous organisms (“gelata”) are increasingly perceived as an important component of marine food webs but remain poorly understood. Their importance as prey in the oceans is extremely difficult to quantify due in part to methodological challenges in verifying predation on gelatinous structures. Miniaturized animal-borne video data loggers now enable feeding events to be monitored from a predator's perspective. We gathered a substantial video dataset (over 350 hours of exploitable footage) from 106 individuals spanning four species of non-gelatinous-specialist predators (penguins), across regions of the southern oceans (areas south of 30°S). We documented nearly 200 cases of targeted attacks on carnivorous gelata by all four species, at all seven studied localities. Our findings emphasize that gelatinous organisms actually represent a widespread but currently under-represented trophic link across the southern oceans, even for endothermic predators, which have high energetic demands. The use of modern technological tools, such as animal-borne video data loggers, will help to correctly identify the ecological niche of gelata. Fil: Thiebot, Jean-Baptiste. National Institute of Polar Research; Japón Fil: Arnould, John PY. Deakin University; Australia Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Ito, Kentaro. SOKENDAI Graduate University for Advanced Studies; Japón Fil: Kato, Akiko. Université de La Rochelle; Francia Fil: Mattern, Thomas. University of Otago; Nueva Zelanda Fil: Mitamura, Hiromichi. Kyoto University; Japón Fil: Noda, Takuji. Kyoto University; Japón Fil: Poupart, Timothée. Deakin University; Australia Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Raclot, Thierry. Université de Strasbourg; Francia Fil: Ropert-Coudert, Yan. Université de La Rochelle; Francia Fil: Sala, Juan Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Seddon, Philip J.. University of Otago; Nueva Zelanda Fil: Sutton, Grace J.. Deakin University; Australia Fil: Yoda, Ken. Nagoya University; Japón Fil: Takahashi, Akinori. SOKENDAI Graduate University for Advanced Studies; Japón

Published
2017

13. Options for modulating intra-specific competition in colonial pinnipeds: the case of harbour seals (Phoca vitulina) in the Wadden Sea

Author

Agustina Gómez-Laich, Victoria J. Hobson, Ursula Siebert, William P. Kay, Andrew Bone, Rory P. Wilson, and Nikolai Liebsch

Subjects
DIVE BEHAVIOUR, media_common.quotation_subject, Foraging, lcsh:Medicine, Marine Biology, Phoca, General Biochemistry, Genetics and Molecular Biology, Competition (biology), SEXUAL SEGREGATION, Ciencias Biológicas, purl.org/becyt/ford/1 [https], QH301, Harbour seal, 14. Life underwater, Pinniped, DIVE DURATION, Sexual segregation, purl.org/becyt/ford/1.6 [https], media_common, computer.programming_language, Ecology, biology, General Neuroscience, Statistics, lcsh:R, Dive duration, General Medicine, Ecología, biology.organism_classification, 3. Good health, Fishery, Dive behaviour, PINNIPED, Harbour, Swim speed, General Agricultural and Biological Sciences, computer, human activities, CIENCIAS NATURALES Y EXACTAS
Abstract

Colonial pinnipeds may be subject to substantial consumptive competition because they are large, slow-moving central place foragers. We examined possible mechanisms for reducing this competition by examining the diving behaviour of harbour seals (Phoca vitulina) after equipping 34 seals (11 females, 23 males) foraging from three locations; Rømø, Denmark and Lorenzenplate and Helgoland, Germany, in the Wadden Sea area with time-depth recorders. Analysis of 319,021 dives revealed little between-colony variation but appreciable inter-sex differences, with males diving deeper than females, but for shorter periods. Males also had higher vertical descent rates. This result suggests that males may have higher overall swim speeds, which would increase higher oxygen consumption, and may explain the shorter dive durations compared to females. Intersex variation in swim speed alone is predicted to lead to fundamental differences in the time use of three-dimensional space, which may help reduce consumptive competition in harbour seals and other colonial pinnipeds. Fil: Wilson, Rory P.. Swansea University; Reino Unido. GEOMAR Helmholtz Centre for Ocean Research; Alemania Fil: Liebsch, Nikloai. Customized Animal Tracking Solutions; Australia Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Kay, William P.. Swansea University; Reino Unido Fil: Bone, Andrew. Swansea University; Reino Unido Fil: Hobson, Victoria J.. Swansea University; Reino Unido Fil: Siebert, Ursula. University of Veterinary Medicine Hannover. Institute for Terrestrial and Aquatic Wildlife Research; Argentina

Published
2015

14. The need for speed: testing acceleration for estimating animal travel rates in terrestrial dead-reckoning systems

Author

Marion Soresina, Emily L. C. Shepard, Owen R. Bidder, Agustina Gómez-Laich, Rory P. Wilson, Lewis G. Halsey, and Flavio Quintana

Subjects
Acceleration, Motor Activity, Biology, Accelerometer, DEAD-RECKONING, Ciencias Biológicas, Telemetry, Data logger, Dead reckoning, Animals, Humans, Proxy (statistics), Ecology, business.industry, OVERALL DYNAMIC, BODY ACCELERATION, Terrestrial locomotion, Bioquímica y Biología Molecular, Geodesy, Calibration, TRACK TORTUOSITY, Geographic Information Systems, Global Positioning System, Regression Analysis, Animal Science and Zoology, business, TELEMETRY, CIENCIAS NATURALES Y EXACTAS, TERRESTRIAL LOCOMOTION
Abstract

Numerous methods are currently available to track animal movements. However, only one of these, dead-reckoning, has the capacity to provide continuous data for animal movements over fine scales. Dead-reckoning has been applied almost exclusively in the study of marine species, in part due to the difficulty of accurately measuring the speed of terrestrial species. In the present study we evaluate the use of accelerometers and a metric known as overall dynamic body acceleration (ODBA) as a proxy for the measurement of speed for use in dead-reckoning. Data were collated from previous studies, for 10 species locomoting on a treadmill and their ODBA measured by an attached data logger. All species except one showed a highly significant linear relationship between speed and ODBA; however, there was appreciable inter- and intra-specific variance in this relationship. ODBA was then used to estimate speed in a simple trial run of a dead-reckoning track. Estimating distance travelled using speed derived from prior calibration for ODBA resulted in appreciable errors. We describe a method by which these errors can be minimised, by periodic ground-truthing (e.g., by GPS or VHF telemetry) of the dead-reckoned track and adjusting the relationship between speed and ODBA until actual known positions and dead-reckoned positions accord. Fil: Bidder, Owen R.. Swansea University; Reino Unido Fil: Soresina, Marion. Swansea University; Reino Unido Fil: Shepard, Emily L. C.. Swansea University; Reino Unido Fil: Halsey, Lewis G.. Roehampton University; Reino Unido Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina. Wildlife Conservation Society; Estados Unidos Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Wilson, Rory P. Swansea University; Reino Unido

Published
2012

15. Buoyed up and slowed down: Speed limits for diving birds in shallow water

Author

Rory P. Wilson, Flavio Quintana, Emily L. C. Shepard, and Agustina Gómez Laich

Subjects
Buoyancy, OVERALL DYNAMIC BODY ACCELERATION, Ecology, Otras Ciencias Biológicas, Aquatic Science, Biology, engineering.material, ODBA, Oceanography, SWIM SPEED, Predation, purl.org/becyt/ford/1 [https], Ciencias Biológicas, Waves and shallow water, Phalacrocorax atriceps, Diving bird, ACCELEROMETRY, DIVING BIRD, engineering, purl.org/becyt/ford/1.6 [https], Ecology, Evolution, Behavior and Systematics, CIENCIAS NATURALES Y EXACTAS
Abstract

In air-breathing animals, the time and energy costs of each dive are primarily determined by depth-related upthrust, swim speed and temperature. While studies have previously investigated how animals should optimise their behaviour in relation to either upthrust or speed they have rarely been examined in tandem. We took overall dynamic body acceleration (ODBA) as a proxy for the mechanical power used during the bottom phases of dives of imperial shags Phalacrocorax atriceps, as these birds forage benthically, in order to define: (1) the minimum power required for swimming at depth and (2) how the use of power above this threshold varied with dive depth. Results showed that ODBA declined with increasing dive depth in a manner correlated with the reduction in upthrust, and that the use of power above that required for prey searching increased with increasing dive depth. This may constitute a response to depth-related patterns in prey availability. We present a model to investigate an alternative hypothesis that the ability of birds to produce burst speeds is also inversely related to the power required to counter buoyancy. Under the model assumptions, achievable burst speeds vary up to 0.7 m s–1 across dive depths from 5 to 60 m. Ultimately, prey preferences cannot be separated from prey fields, but we suggest that this model may provide insight into the ability of air-breathing divers to pursue various prey types according to dive depth. Fil: Shepard, Emily L. C.. Swansea University; Reino Unido Fil: Wilson, Rory P.. Swansea University; Reino Unido Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Wildlife Conservation Society; Estados Unidos

Published
2010

16. Foraging behaviour and diet of American Oystercatchers in a Patagonian intertidal area affected by nutrient loading

Author

Marco Favero, Mariano Javier Albano, Tomas Atilio Luppi, Daniel Augusto Cardoni, Germán Oscar García, Oscar Iribarne, Agustina Gómez Laich, and Juan Pablo Isacch

Subjects
0106 biological sciences, Foraging, Intertidal zone, Macroalgal bloom, Biology, 010603 evolutionary biology, 01 natural sciences, Algal bloom, 010605 ornithology, Predation, Ciencias Biológicas, Oystercatcher, Ecology, Evolution, Behavior and Systematics, Nature and Landscape Conservation, Biomass (ecology), Ecology, Ecología, biology.organism_classification, Diet, Fishery, Animal Science and Zoology, Eutrophication, Bay, CIENCIAS NATURALES Y EXACTAS, Foraging behaviour
Abstract

Eutrophication increases the biomass of opportunistic green macroalgae that covers intertidal zones, and macroalgal blooms may affect the intertidal invertebrate community and predation of invertebrates by shorebirds. In San Antonio Bay, Argentina, eutrophication from the discharge of wastewater from a coastal town produces periodic macroalgal blooms. Our aim was to assess if macroalgal blooms affect the foraging behaviour and diet of the American Oystercatcher (Haematopus palliatus). A macroalgal transplant experiment was performed in order to evaluate how epifaunal species respond to a macroalgal canopy. The availability of prey for Oystercatchers, and their foraging behaviour and diet, were analysed in two paired channels with different nutrient loadings. Oystercatchers generally ate the most profitable prey and avoided prey with a profitability value lower than the mean rate of energy intake. During the macroalgal blooms, Oystercatchers avoided two prey species with high profitability values, shifting their foraging strategy and feeding onto a suboptimal prey but with a high encounter rate. Our results suggest that nutrient loadings and the macroalgal blooms that they generate have effects on the diet and foraging behaviour of Oystercatchers, which results in an increase of the average rate of energy intake of Oystercatchers foraging along the channel subject to a macroalgal bloom. Fil: García, Germán Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Isacch, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Albano, Mariano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Favero, Marco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Cardoni, Daniel Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Luppi, Tomas Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Iribarne, Oscar Osvaldo. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Published
2010

17. Pushed for time or saving on fuel: Fine-scale energy budgets shed light on currencies in a diving bird

Author

Rory P. Wilson, Emily L. C. Shepard, Dan W. Forman, Flavio Quintana, and Agustina Gómez Laich

Subjects
Time Factors, CENTRAL PLACE FORAGING, Foraging, Net energy, Energy metabolism, Biology, Breeding, ACCELERATION, General Biochemistry, Genetics and Molecular Biology, Birds, Ciencias Biológicas, Research articles, Statistics, Animals, Energy maximization, General Environmental Science, General Immunology and Microbiology, Ecology, General Medicine, Instantaneous energy, Ecología, ENERGY EXPENDITURE, Phalacrocorax atriceps, Diving bird, Energy expenditure, Flight, Animal, Predatory Behavior, CURRENCY, Seasons, FORAGING STRATEGY, TIME-ENERGY BUDGET, General Agricultural and Biological Sciences, Energy Metabolism, CIENCIAS NATURALES Y EXACTAS
Abstract

Animals may forage using different currencies depending on whether time minimization or energy maximization is more pertinent at the time. Assessment of net energy acquisition requires detailed information on instantaneous activity-specific power use, which varies according to animal performance, being influenced, for example, by speed and prey loading, and which has not been measured before in wild animals. We used a new proxy for instantaneous energy expenditure (overall dynamic body acceleration), to quantify foraging effort in a model species, the imperial shag Phalacrocorax atriceps, during diving. Power costs varied nonlinearly with depth exploited owing to depth-related buoyancy. Consequently, solutions for maximizing the gross rate of gain and energetic efficiency differed for dives to any given depth. Dive effort in free-ranging imperial shags measured during the breeding season was consistent with a strategy to maximize the gross rate of energy gain. We suggest that the divergence of time and energy costs with dive depth has implications for the measurement of dive efficiency across diverse diving taxa. Fil: Shepard, Emily L. C.. Swansea University; Reino Unido Fil: Wilson, Rory P.. Swansea University; Reino Unido Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina. Wildlife Conservation Society; Estados Unidos Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Forman, Dan W.. Swansea University; Reino Unido

Published
2009

18. Spatio-temporal variation in mortality rates of White-chinned Petrels Procellaria aequinoctialis interacting with longliners in the south-west Atlantic

Author

Agustina Gómez Laich and Marco Favero

Subjects
Ecology, biology, Petrel, Forestry, Ecología, biology.organism_classification, LONGLINERS, White-chinned petrel, WHITE CHINNED PETREL, Ciencias Biológicas, Procellaria aequinoctialis, Geography, PROCELLARIA AEQUINOCTIALIS, Animal Science and Zoology, INCIDENTAL CAPTURE, CIENCIAS NATURALES Y EXACTAS, Nature and Landscape Conservation
Abstract

The White-chinned Petrel Procellaria aequinoctialis is the second most commonly captured species by Argentinean longliners. The severe declines that this species has experienced in some of its populations (e.g. South Georgia Islands) have been principally attributed to incidental mortality associated with longliners. In this study we analyse the spatio-temporal variability in the mortality rates of White-chinned Petrels on the Patagonian Shelf and the effects that environmental and operational variability have on such mortality. The average capture rate (¡ 1 SD) for the period 1999–2003 was 0.014 ¡ 0.090 White-chinned Petrels for every 1,000 hooks deployed. Higher capture rates were observed when short longlines were deployed. Capture rates were not affected by the wind speed or by the time to the full moon. The distribution of the captures differed throughout the year. During autumn–winter most captures took place in the north of the Patagonian Shelf, whereas during spring–summer incidental captures occurred principally to the south between 45uS and 50uS. El Petrel Barba Blanca Procellaria aequinoctialis constituye la segunda especie ma´s frecuentemente capturada por la flota palangrera Argentina. Los importantes decrecimientos poblacionales observados en algunas poblaciones de esta especie (e.g. Islas Georgias del Sur) han sido principalmente atribuidos a la mortalidad incidental asociada a embarcaciones palangreras. En este trabajo se analizo´ la variacio´n espacio- temporal en las tasas de captura incidental del Petrel Barba Blanca a lo largo de la Plataforma Continental Argentina y se estudio´ el efecto que diferentes variables ambientales y operacionales tienen sobre la mortalidad incidental de esta especie. La tasa de captura promedio (¡ d.s) durante el periodo 1999–2003 fue de 0.014 ¡ 0.090 Petreles Barba Blanca cada 1.000 anzuelos. Mayores tasas de captura fueron registradas al utilizar palangres cortos. No se observo´ un efecto de la intensidad del viento ni de la distancia a la luna llena sobre las tasas de captura. La distribucio´n de las capturas difirio´ a lo largo del an˜ o. Durante el oton˜ o-invierno la mayorı´a de las capturas estuvieron localizadas al norte de la Plataforma Continental Argentina, mientras que durante los meses de primavera-verano las capturas estuvieron localizadas principalmente entre los 45uS y 50uS. Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina Fil: Favero, Marco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina

Published
2007

19. Foraging behaviour and diet of American Oystercatchers in a Patagonian intertidal area affected by nutrient loading.

Author

Germán Oscar García, Juan Pablo Isacch, Agustina Gómez Laich, Mariano Albano, Marco Favero, Daniel Augusto Cardoni, Tomás Luppi, and Oscar Iribarne

Subjects
BIRD behavior, FORAGING behavior, AMERICAN oystercatcher, NUTRIENT cycles, DIET, BIOMASS, ALGAL blooms, INTERTIDAL zonation
Abstract

Eutrophication increases the biomass of opportunistic green macroalgae that covers intertidal zones, and macroalgal blooms may affect the intertidal invertebrate community and predation of invertebrates by shorebirds. In San Antonio Bay, Argentina, eutrophication from the discharge of wastewater from a coastal town produces periodic macroalgal blooms. Our aim was to assess if macroalgal blooms affect the foraging behaviour and diet of the American Oystercatcher (Haematopus palliatus). A macroalgal transplant experiment was performed in order to evaluate how epifaunal species respond to a macroalgal canopy. The availability of prey for Oystercatchers, and their foraging behaviour and diet, were analysed in two paired channels with different nutrient loadings. Oystercatchers generally ate the most profitable prey and avoided prey with a profitability value lower than the mean rate of energy intake. During the macroalgal blooms, Oystercatchers avoided two prey species with high profitability values, shifting their foraging strategy and feeding onto a suboptimal prey but with a high encounter rate. Our results suggest that nutrient loadings and the macroalgal blooms that they generate have effects on the diet and foraging behaviour of Oystercatchers, which results in an increase of the average rate of energy intake of Oystercatchers foraging along the channel subject to a macroalgal bloom. [ABSTRACT FROM AUTHOR]

Published
2010

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