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Auteur Dalleau, M.; Kramer-Schadt, S.; Gangat, Y.; Bourjea, J.; Lajoie, G.; Grimm, V. doi  openurl
  Titre Modeling the emergence of migratory corridors and foraging hot spots of the green sea turtle Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecol. Evol.  
  Volume Numéro Pages  
  Mots-Clés aldabra atoll; chelonia-mydas; connectivity; corridors; individual-based model; leatherback turtles; marine turtles; migration; movement; penghu archipelago; population-dynamics; remigration intervals; satellite-tracking; sea turtle; wan-an island  
  Résumé Environmental factors shape the spatial distribution and dynamics of populations. Understanding how these factors interact with movement behavior is critical for efficient conservation, in particular for migratory species. Adult female green sea turtles, Chelonia mydas, migrate between foraging and nesting sites that are generally separated by thousands of kilometers. As an emblematic endangered species, green turtles have been intensively studied, with a focus on nesting, migration, and foraging. Nevertheless, few attempts integrated these behaviors and their trade-offs by considering the spatial configurations of foraging and nesting grounds as well as environmental heterogeneity like oceanic currents and food distribution. We developed an individual-based model to investigate the impact of local environmental conditions on emerging migratory corridors and reproductive output and to thereby identify conservation priority sites. The model integrates movement, nesting, and foraging behavior. Despite being largely conceptual, the model captured realistic movement patterns which confirm field studies. The spatial distribution of migratory corridors and foraging hot spots was mostly constrained by features of the regional landscape, such as nesting site locations, distribution of feeding patches, and oceanic currents. These constraints also explained the mixing patterns in regional forager communities. By implementing alternative decision strategies of the turtles, we found that foraging site fidelity and nesting investment, two characteristics of green turtles' biology, are favorable strategies under unpredictable environmental conditions affecting their habitats. Based on our results, we propose specific guidelines for the regional conservation of green turtles as well as future research suggestions advancing spatial ecology of sea turtles. Being implemented in an easy to learn open-source software, our model can coevolve with the collection and analysis of new data on energy budget and movement into a generic tool for sea turtle research and conservation. Our modeling approach could also be useful for supporting the conservation of other migratory marine animals.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2045-7758 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000481747800001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2621  
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Auteur Kadar, J.; Ladds, M.; Mourier, J.; Day, J.; Brown, C. doi  openurl
  Titre Acoustic accelerometry reveals diel activity patterns in premigratory Port Jackson sharks Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecol. Evol.  
  Volume Numéro Pages  
  Mots-Clés accelerometer; activity budgets; activity pattern; behavior; diel cycle; habitat; heterodontus-portusjacksoni; lobsters; migratory restlessness; movement; Port Jackson shark; reef sharks; regression; root mean square acceleration; vertical migrations; wild  
  Résumé Distinguishing the factors that influence activity within a species advances understanding of their behavior and ecology. Continuous observation in the marine environment is not feasible but biotelemetry devices provide an opportunity for detailed analysis of movements and activity patterns. This study investigated the detail that calibration of accelerometers measuring root mean square (RMS) acceleration with video footage can add to understanding the activity patterns of male and female Port Jackson sharks (Heterodontus portusjacksoni) in a captive environment. Linear regression was used to relate RMS acceleration output to time-matched behavior captured on video to quantify diel activity patterns. To validate captive data, diel patterns from captive sharks were compared with diel movement data from free-ranging sharks using passive acoustic tracking. The RMS acceleration data showed captive sharks exhibited nocturnal diel patterns peaking during the late evening before midnight and decreasing before sunrise. Correlation analysis revealed that captive animals displayed similar activity patterns to free-ranging sharks. The timing of wild shark departures for migration in the late breeding season corresponded with elevated diel activity at night within the captive individuals, suggesting a form of migratory restlessness in captivity. By directly relating RMS acceleration output to activity level, we show that sex, time of day, and sex-specific seasonal behavior all influenced activity levels. This study contributes to a growing body of evidence that RMS acceleration data are a promising method to determine activity patterns of cryptic marine animals and can provide more detailed information when validated in captivity.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2045-7758 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000478172800001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2623  
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Auteur Siegwalt, F.; Benhamou, S.; Girondot, M.; Jeantet, L.; Martin, J.; Bonola, M.; Lelong, P.; Grand, C.; Chambault, P.; Benhalilou, A.; Murgale, C.; Maillet, T.; Andreani, L.; Campistron, G.; Jacaria, F.; Hielard, G.; Arque, A.; Etienne, D.; Gresser, J.; Regis, S.; Lecerf, N.; Frouin, C.; Lefebvre, F.; Aubert, N.; Vedie, F.; Barnerias, C.; Thieulle, L.; Guimera, C.; Bouaziz, M.; Pinson, A.; Flora, F.; George, F.; Eggenspieler, J.; Woignier, T.; Allenou, J.-P.; Louis-Jean, L.; Chanteur, B.; Beranger, C.; Crillon, J.; Brador, A.; Habold, C.; Le Maho, Y.; Robin, J.-P.; Chevallier, D. doi  openurl
  Titre High fidelity of sea turtles to their foraging grounds revealed by satellite tracking and capture-mark-recapture: New insights for the establishment of key marine conservation areas Type Article scientifique
  Année 2020 Publication Revue Abrégée Biol. Conserv.  
  Volume 250 Numéro Pages 108742  
  Mots-Clés chelonia-mydas; Developmental area; Green turtle; growth; habitat use; Habitat use; Home range; home-range; immature green turtles; juvenile; lost years; movement patterns; multistate models; Residency; Seagrass; survival  
  Résumé Movement ecology studies are essential to protect highly mobile threatened species such as the green turtle (Chelonia mydas), classified as an endangered species by the IUCN. In 2019, the South Atlantic subpopulation has been downlisted to 'Least Concern', but the maintenance of this status strongly relies on the pursuit of research and conservation, especially on immatures, which contribute to the demographic renewal of this subpopulation. Identifying marine areas used by immatures is therefore crucial to implement efficient measures for the conservation of sea turtles in the Caribbean. We analysed data of capture-mark-recapture of 107 (out of 299) immatures recaptured at least once in Martinique, and satellite tracked 24 immatures to investigate their site fidelity and habitat use. Our results revealed a strong fidelity to foraging grounds, with mean residence times higher than 2 years, and with a high degree of affinity for specific areas within the coastal marine vegetation strip. Home ranges (95% kernel contour) and core areas (50% kernel contour) varied from 0.17 to 235.13 km(2) (mean +/- SD = 30.73 +/- 54.34 km(2)) and from 0.03 to 22.66 km(2) (mean +/- SD = 2.95 +/- 5.06 km(2)), respectively. Our findings shed light on a critical developmental area for immature green turtles in the French West Indies, and should help to refine Regional Management Units and reinforce the cooperative network aiming at ensuring conservation of the species at international scale.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0006-3207 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000582432900003 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2886  
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Auteur Carpentier, A.S.; Berthe, C.; Ender, I.; Jaine, F.R.A.; Mourier, J.; Stevens, G.; De Rosemont, M.; Clua, E. doi  openurl
  Titre Preliminary insights into the population characteristics and distribution of reef (Mobula alfredi) and oceanic (M. birostris) manta rays in French Polynesia Type Article scientifique
  Année 2019 Publication Revue Abrégée Coral Reefs  
  Volume 38 Numéro 6 Pages 1197-1210  
  Mots-Clés aggregation; australia; bottle-nosed dolphins; california; Citizen science; conservation; Ecotourism management; habitat use; identification; marine park; movements; sharks; Site fidelity; Spatial connectivity; Sympatry  
  Résumé In French Polynesia, both currently recognized manta ray species, Mobula alfredi and M. birostris, are observed. Despite being an important cultural asset and generating significant economic benefits through manta ray watching tourism, published data on the ecology and threats to these species in the region are scarce. Based on an 18-year dataset of sighting records collected by citizen scientists and during two scientific expeditions, this study provides the first insights into the population characteristics and regional distribution of the two manta ray species in French Polynesia. A total of 1347 manta ray photographs (1337 for M. alfredi and 10 for M. birostris) were examined for the period January 2001-December 2017, with photo-identification techniques leading to the successful identification of 317 individual M. alfredi and 10 individual M. birostris throughout the Society, Tuamotu and Marquesas Islands. We provide the first confirmation of sympatric distribution of both species in the Society Islands. Our results highlight strong and long-term site fidelity of M. alfredi individuals to certain aggregation sites (> 9 years for 16 individuals) and reveal some degree of connectivity between populations, with 10 individuals recorded moving between islands located up to 50 km apart. Analysis of photographs of individuals bearing sub-lethal injuries (n = 68) suggests that M. alfredi are more likely to be injured at inhabited islands (Maupiti or Bora Bora; 75% of all injured individuals) than at uninhabited islands, with 75% of injuries related to boat propeller strikes and fishing gear entanglements. Our findings emphasize the need for further research to allow for a comprehensive evaluation of population structure, size and threats to manta rays in this region.  
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  ISSN 0722-4028 ISBN Médium  
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  Notes WOS:000496024100010 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2658  
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Auteur van Gils, J.A.; van der Geest, M.; De Meulenaer, B.; Gillis, H.; Piersma, T.; Folmer, E.O. url  doi
openurl 
  Titre Moving on with foraging theory: incorporating movement decisions into the functional response of a gregarious shorebird Type Article scientifique
  Année 2015 Publication Revue Abrégée Journal of Animal Ecology  
  Volume 84 Numéro Pages 554-564  
  Mots-Clés competition continuous-time Markov chain cryptic interference diet distribution habitat choice intake rate movement ecology predation toxic prey SPATIAL-DISTRIBUTION RED KNOTS MODELING INTERFERENCE CRYPTIC INTERFERENCE STOCHASTIC VERSION BEHAVIORAL ECOLOGY MULTISTATE MODELS BANC-DARGUIN GROUP-SIZE PREY Ecology Zoology  
  Résumé 1. Models relating intake rate to food abundance and competitor density (generalized functional response models) can predict forager distributions and movements between patches, but we lack understanding of how distributions and small-scale movements by the foragers themselves affect intake rates. Using a state-of-the-art approach based on continuous-time Markov chain dynamics, we add realism to classic functional response models by acknowledging that the chances to encounter food and competitors are influenced by movement decisions, and, vice versa, that movement decisions are influenced by these encounters. We used a multi-state modelling framework to construct a stochastic functional response model in which foragers alternate between three behavioural states: searching, handling and moving. Using behavioural observations on a molluscivore migrant shorebird (red knot, Calidris canutus canutus), at its main wintering area (Banc d'Arguin, Mauritania), we estimated transition rates between foraging states as a function of conspecific densities and densities of the two main bivalve prey. Intake rate decreased with conspecific density. This interference effect was not due to decreased searching efficiency, but resulted from time lost to avoidance movements. Red knots showed a strong functional response to one prey (Dosinia isocardia), but a weak response to the other prey (Loripes lucinalis). This corroborates predictions from a recently developed optimal diet model that accounts for the mildly toxic effects due to consuming Loripes. Using model averaging across the most plausible multi-state models, the fully parameterized functional response model was then used to predict intake rate for an independent data set on habitat choice by red knot. Comparison of the sites selected by red knots with random sampling sites showed that the birds fed at sites with higher than average Loripes and Dosinia densities, that is sites for which we predicted higher than average intake rates. We discuss the limitations of Holling's classic functional response model which ignores movement and the limitations of contemporary movement ecological theory that ignores consumer-resource interactions. With the rapid advancement of technologies to track movements of individual foragers at fine spatial scales, the time is ripe to integrate descriptive tracking studies with stochastic movement-based functional response models.  
  Adresse [van Gils, Jan A.; van der Geest, Matthijs; De Meulenaer, Brecht; Gillis, Hanneke; Piersma, Theunis; Folmer, Eelke O.] NIOZ Royal Netherlands Inst Sea Res, Dept Marine Ecol, NL-1790 AB Den Burg, Texel, Netherlands. [van der Geest, Matthijs; Piersma, Theunis] Univ Groningen, Anim Ecol Grp, Ctr Ecol & Evolutionary Studies CEES, Chair Global Flyway Ecol, NL-9700 CC Groningen, Netherlands. van Gils, JA (reprint author), NIOZ Royal Netherlands Inst Sea Res, Dept Marine Ecol, POB 59, NL-1790 AB Den Burg, Texel, Netherlands. Jan.van.Gils@nioz.nl  
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  Langue English Langue du Résumé Titre Original  
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  ISSN 0021-8790 ISBN Médium  
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  Notes ISI Document Delivery No.: CB9RB Times Cited: 0 Cited Reference Count: 61 van Gils, Jan A. van der Geest, Matthijs De Meulenaer, Brecht Gillis, Hanneke Piersma, Theunis Folmer, Eelke O. NWO WOTRO [W.01.65.221.00]; NWO [R 84-639]; NWO VIDI [864.09.002] We thank Parc National du Banc d'Arguin (PNBA) for their hospitality, the hosting of our presence and the permission to work in and from the Iwik scientific station. Lemhaba ould Yarba made the logistic arrangements. Joop van Eerbeek, Erik J. Jansen, Han Olff and El-Hacen Mohamed El-Hacen helped collecting and sorting benthos samples. Valuable comments on the manuscript were given by Allert Bijleveld, Jaap van der Meer, Ola Olsson, Thomas Oudman, Isabel M. Smallegange, an anonymous referee and by the 'literature club' of the Centre for Integrative Ecology during JAvG's sabbatical at Deakin University. Dick Visser polished the figures. This work is supported by an NWO WOTRO Integrated Programme grant (W.01.65.221.00) to TP, an NWO travel grant (R 84-639) to EOF, and an NWO VIDI grant (864.09.002) to JAvG. 0 WILEY-BLACKWELL HOBOKEN J ANIM ECOL Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ 1412 collection 1383  
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