%0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Imzilen, Taha %A Lett, Christophe %A Chassot, Emmanuel %A Kaplan, David %T Spatial management can significantly reduce dFAD beachings in Indian and Atlantic Ocean tropical tuna purse seine fisheries %D 2021 %L fdi:010081109 %G ENG %J Biological Conservation %@ 0006-3207 %K Marine pollution ; Fishing debris ; Coral reefs ; Fish aggregating device (FAD) ; Ocean currents %K ATLANTIQUE ; OCEAN INDIEN %M ISI:000623545800002 %P 108939 [9 ] %R 10.1016/j.biocon.2020.108939 %U https://www.documentation.ird.fr/hor/fdi:010081109 %> https://www.documentation.ird.fr/intranet/publi/2021-05/010081109.pdf %V 254 %W Horizon (IRD) %X Debris from fisheries pose significant threats to coastal marine ecosystems worldwide. Tropical tuna purse seine fisheries contribute to this problem via the construction and deployment of thousands of human-made drifting fish aggregating devices (dFADs) annually, many of which end up beaching in coastal areas. Here, we analyzed approximately 40,000 dFAD trajectories in the Indian Ocean and 12,000 dFAD trajectories in the Atlantic Ocean deployed over the decade 2008-2017 to identify where and when beachings occur. We find that there is tremendous promise for reducing beaching events by prohibiting deployments in areas most likely to lead to a beaching. For example, our results indicate that 21% to 40% (depending on effort redistribution after closure) of beachings can be prevented if deployments are prohibited in areas in the south of 8 degrees S latitude, the Somali zone in winter, and the western Maldives in summer for the Indian Ocean, and in an elongated strip of areas adjacent to the western African coast for the Atlantic Ocean. In both oceans, the riskiest areas for beaching are not coincident with areas of high dFAD deployment activity, suggesting that these closures could be implemented with relatively minimal impact to fisheries. Furthermore, the existence of clear hotspots for beaching likelihood and the high rates of putative recovery of dFAD buoys by small-scale fishers in some areas suggests that early warning systems and dFAD recovery programs may be effective in areas that cannot be protected via closures if appropriate incentives can be provided to local partners for participating in these programs. %$ 038 ; 040 %0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Merigot, B. %A Gaertner, Jean-Claude %A Amour, A. B. %A Carbonara, P. %A Esteban, A. %A Garcia-Ruiz, C. %A Gristina, M. %A Imzilen, Taha %A Jadaud, A. %A Joksimovic, A. %A Kavadas, S. %A Kolitari, J. %A Maina, I. %A Maiorano, P. %A Manfredi, C. %A Micallef, R. %A Peristeraki, P. %A Relini, G. %A Sbrana, M. %A Spedicato, M. T. %A Thasitis, I. %A Vittori, S. %A Vrgoc, N. %T Stability of the relationships among demersal fish assemblages and environmental-trawling drivers at large spatio-temporal scales in the northern Mediterranean Sea %B Mediterranean demersal resources and ecosystems : 25 years of MEDITS trawl surveys %D 2019 %E Spedicato, M.T. %E Tserpes, G. %E Mérigot, B. %E Massuti, E. %L fdi:010077738 %G ENG %J Scientia Marina %@ 0214-8358 %K species composition ; stability ; demersal assemblages ; environment ; fishing pressure ; large scale ; co-inertia analysis ; STATICO-CoA %K MEDITERRANEE %M ISI:000504829900012 %N 1 %P 153-163 %R 10.3989/scimar.04954.30A %U https://www.documentation.ird.fr/hor/fdi:010077738 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers20-01/010077738.pdf %V 83 %W Horizon (IRD) %X Trawling pressure and environmental changes may affect the composition of fish assemblages. Our knowledge on large spatio-temporal patterns of demersal fish composition remains incomplete for the Mediterranean Sea. We investigated (1) the spatio-temporal stability of demersal assemblages, (2) the relationships between these assemblages and potential structuring factors (trawling pressure and environmental conditions) in order to assess the dynamic of the assemblage structure at the scale of the northern Mediterranean Sea. We analysed a dataset of 18062 hauls from 10 to 800 m depth performed annually during the last two decades across 17 Geographical Sub-Areas (GSAs) (MEDITS program). A multi-table analysis (STATICO-CoA) evidenced a strong inter-GSAs stability in the organization of assemblages, with specificities for some GSAs. The most stable structuring factors were linked to combined gradients of chlorophyll a, phytoplancton carbon biomass and temperature, inversely correlated with depth, salinity and nutrient gradients (axis 1 of the STATICO-CoA compromise, 93.74% of the total variability). A common pattern linking the distribution of species to these environmental gradients was evidenced for most of the 17 GSAs. Estimate of trawling pressure showed a minor role in the organization of the assemblages for the spatial scale and years investigated (axis 2. 4.67%). %$ 040 ; 036 %0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Imzilen, Taha %A Chassot, Emmanuel %A Barde, Julien %A Demarcq, Hervé %A Maufroy, A. %A Roa-Pascuali, L. %A Ternon, J. F. %A Lett, Christophe %T Fish aggregating devices drift like oceanographic drifters in the near-surface currents of the Atlantic and Indian Oceans %D 2019 %L fdi:010075192 %G ENG %J Progress in Oceanography %@ 0079-6611 %K Drifter ; Fish aggregating device ; Fisheries ; Lagrangian transport ; Oceanography ; Surface currents %K ATLANTIQUE ; OCEAN INDIEN %M ISI:000457950800008 %P 108-127 %R 10.1016/j.pocean.2018.11.007 %U https://www.documentation.ird.fr/hor/fdi:010075192 %> https://www.documentation.ird.fr/intranet/publi/2019/02/010075192.pdf %V 171 %W Horizon (IRD) %X Knowledge of ocean surface dynamics is crucial for oceanographic and climate research. The satellite-tracked movements of hundreds of drifters deployed by research and voluntary observing vessels provide high-frequency and high-resolution information on near-surface currents around the globe. Consequently, they constitute a major component of the Global Ocean Observing System (GOOS). However, maintaining this array is costly and in some oceanic regions such as the tropics, spatio-temporal coverage is limited. Here, we demonstrate that the GPS-buoy equipped fish aggregating devices (FADs) used in tropical tuna fisheries to increase fishing success are also capable of providing comparable near-surface current information. We analyzed millions of position data collected between 2008 and 2014 from more than 15,000 FADs and 2,000 drifters, and combined this information with remotely-sensed near-surface current data to demonstrate that the surface velocity components of FADs and drifters are highly correlated in the Atlantic and Indian Oceans. While it was noted that the subsurface structures of FADs did slow them down relative to the drifters, particularly in the Atlantic Ocean, this bias was measurable and could be accounted for in future studies. Our findings show that the physical meteorological and oceanographic data collected by fishermen could provide an invaluable source of information to the GOOS. Furthermore, by forging closer collaborations with the fishing industry and ensuring their contributions to global ocean databases are properly acknowledged, there is significant scope to capture this data more effectively. %$ 040 ; 032 %0 Book Section %9 OS CH : Chapitres d'ouvrages scientifiques %A Nieblas, A.E. %A Barde, Julien %A Louys, J. %A Lucas, J. %A Assan, C. %A Imzilen, Taha %A Dalleau, C. %A Gerry, C. %A Chassot, Emmanuel %T Seychelles VMS/logbook comparison for tuna fisheries (FAO Area 51) %B Global atlas of AIS-based fishing activity : challenges and opportunities %C Rome %D 2019 %E Taconet, M. %E Kroodsma, D. %E Fernandes, J.A. %L fdi:010079230 %G ENG %I FAO %@ 978-92-5-131964-2 %K SEYCHELLES ; OCEAN INDIEN %P 79-108 %U https://www.documentation.ird.fr/hor/fdi:010079230 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers20-06/010079230.pdf %W Horizon (IRD) %X Seychelles high seas tuna fleets have a high AIS use with a transmission frequency considerably higher than that of VMS. However, AIS has far fewer transmissions than VMS and many more gaps in transmission longer than a few hours. The spatial coverage of the AIS data is good for Seychelles longline vessels, with acceptable coverage over the core fishing grounds. By contrast, AIS data are deficient for purse seiners and supply vessels with most data only present around ports due to the switch-off behavior linked to the piracy threat.Consistent with data coverage, AIS seems to be very useful in describing the spatiotemporal patterns of the longline fishery and for identifying fishing hotspots. The GFW neural net algorithm predicts well the fishing operations for longliners but predictions for purse seiners are not informative. Metrics for effort at the scale of 5° x 5° squares, such as those typically used by tuna regional fisheries management organizations (RFMOs) for longline fisheries, are well correlated between logbooks and GFW algorithms. Thus, GFW is able to accurately distinguish fishing from non-fishing activities for longliners. However, the frequent breaks in transmission, perhaps due to issues with AIS reception, lead to consistent underprediction by AIS and GFW algorithms of the "true" patterns shown using VMS and logbook data. The increased satellite coverage observed between 2016 and 2017 resulted in improved GFW algorithm performance in deriving estimations of longline fishing effort.The relationships between GFW predictions of longline fishing and effort could be useful in data-poor fisheries where poor collection and management systems may prevent the reporting of spatial effort to the RFMO. In such cases, the availability of AIS or VMS data combined with information on the number of hooks deployed per operation may enable predictions of gridded effort, which would improve compliance with the Conservation and Management Measures. %$ 040 ; 036 ; 032 %0 Conference Proceedings %9 ACTI : Communications avec actes dans un congrès international %A Nieblas, A.E. %A Barde, Julien %A Bernard, S. %A Imzilen, Taha %A Kerzerho, V. %A Rouyer, S. %A Bonhommeau, S. %T Enrichment of trajectories with environmental data, and standardization of tagging data using NetCDF %C Victoria Mahé %D 2018 %L fdi:010075958 %G ENG %I CTOI %K ATLANTIQUE ; OCEAN INDIEN %N IOTC–2018–WPDCS14–25_Rev1 %P 12 multigr. %U https://www.documentation.ird.fr/hor/fdi:010075958 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers19-05/010075958.pdf %W Horizon (IRD) %X Geolocalisation and trajectory analysis can aid in understanding the ecological processes driving an organism. By associating satellite-derived environmental data with individual trajectories of electronically-tagged organisms, it could be possible to define environmental characteristics of the tagged species' functional habitats (i.e., reproduction, nutrition). These data can also help identify biotic envelopes or predict the effects of climate change on marine species distributions. The objective of the present work, undertaken as a collaboration between IFREMER and IRD, is to standardize electronic tag data files into network common data format (NetCDF) format, following the standards defined within the POPSTAR project for tag data (doi http://dx.doi.org/10.13155/34980), and enrich the positional data with satellite-derived surface environment data (e.g., sea surface temperature, salinity, sea level) and model-derived environment data at observed depths (e.g., temperature, salinity, currents). We accounted for positional uncertainty using 95%, 75%, and 50% uncertainty polygons around the estimated positions of individuals. We summarised environmental conditions within these uncertainty polygons using the mean, minimum, maximum, quantiles, and standard deviation of the selected enrichment parameter. We generated generic codes to enable the automatic enrichment of position data from points and polygons. Furthermore, we developed algorithms to convert the enriched data into NetCDF format for subsequent visualisation and analysis. %B Groupe de Travail sur la Collecte des Données et les Statistiques : GTCDS14 %8 2018/11/29 - 201812/02 %$ 036 ; 126 %0 Conference Proceedings %9 ACTI : Communications avec actes dans un congrès international %A Barde, Julien %A Nieblas, A.E. %A Blondel, E. %A Bodin, Nathalie %A Bonhommeau, S. %A Chassot, Emmanuel %A Imzilen, Taha %T Describing and accessing biological and tagging data %C Victoria Mahé %D 2018 %L fdi:010075959 %G ENG %I CTOI %K OCEAN INDIEN %N IOTC–2018–WPDCS14–25_Rev1 %P 12 multigr. %U https://www.documentation.ird.fr/hor/fdi:010075959 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers19-05/010075959.pdf %W Horizon (IRD) %B Groupe de Travail sur la Collecte des Données et les Statistiques : GTCDS14 %8 2018/11/29 - 2018/12/02 %$ 034 ; 122 %0 Conference Proceedings %9 ACTI : Communications avec actes dans un congrès international %A Imzilen, Taha %A Lett, Christophe %A Chassot, Emmanuel %A Barde, Julien %T Modeling trajectories of fish aggregating devices with satellite images : use cases related to fisheries %C Victoria Mahé %D 2016 %L fdi:010069095 %G ENG %I CTOI %K OCEAN INDIEN ; SEYCHELLES %N IOTC–2016–WPDCS12–29 %P 11 multigr. %U https://www.documentation.ird.fr/hor/fdi:010069095 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-01/010069095.pdf %W Horizon (IRD) %X This note presents some work related to analysis of FAD trajectories (observed and simulated) by using additional observations of Drifters and related simulations with a model (Ichthyop) driven by satellite products for sea surface currents (OSCAR). We have different goals in mind: comparisons of FADs and surface drifters trajectories (by comparing in situ observations and remote sensing data), predicting the areas where FAD could drift, prevent damages on coral reefs, check if some species are following FADs. However to deal with these use cases, the execution of thousands of simulations is a prerequisite. We propose to execute the runs of the model online with following benefits: all users can run the model remotely without having to configure anything and with additional machine resources, outputs of the model can be stored and shared online and are thus already available for the next steps (post processing). We present and discuss some of the possible use cases and preliminary results. %B Groupe de Travail sur la Collecte des Données et les Statistiques (GTCDS) = Working Party on Data Collection and Statistics (WPDCS) %8 2016/11/17 %$ 040 ; 126