French Research Institute for Exploitation of the Sea
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Managing milky waters
No full textThe waters off the Peruvian coast are highly productive, but they are experiencing extreme phenomena that pose a direct threat not only to fishing, but also to aquaculture, particularly scallop farming, which employs some 200,000 people in the country
Shining a light on invisible biodiversity
No full textBased on technology that has been in use for over twenty years, the study of DNA fragments left behind by organisms in the environment is undergoing unprecedented development thanks to a revolution on two fronts - microelectronic and digita
The birds' share
No full textBetween sustainable fishing and overfishing, it is a matter of numbers. What is the acceptable catch limit to allow the renewal of fish stocks and the maintenance of the rest of the ecosystem, particularly seabird populations? That is the questio
Food security in Polynesia
No full textClimate change is making French Polynesia more vulnerable, affecting food security in particular. lt is therefore necessary to implement adaptation strategies
Rapport d’expertise sur les rapports intermédiaires à 1 an d’état initial de l’environnement des parcs éoliens flottants de Méditerranée (AO6 - Occitanie)
No full textCe rapport d’expertise présente les observations de l’Ifremer sur les rapports intermédiaires à 1 an d’état initial de l’environnement de la zone des parcs éoliens flottants de Méditerranée dite « La Narbonnaise » en Occitanie, sur les compartiments « qualité de l’eau », « qualité des sédiments », « habitats et peuplement benthiques » et « poissons et méga-invertébrés »
Use of capture based metagenomic to assess human enteric virus diversity in sewage and shellfish samples
No full textHuman sewage is the main source of contamination of environmental waters with human enteric viruses, that can contaminate food such as shellfish. Metagenomic represents a new way of analyzing viral diversity through an a priori massive parallel sequencing approach. However, the precise identification of enteric viruses in sewage or shellfish matrices, is still challenging due to the low viral load, large diversity of viral genera and the large amounts of matrix masking viral sequences. This work compared three commercial kits using capture-based enrichment during the library preparation, for the diversity of detected enteric viruses and for the identification of viral strains in sewage and shellfish samples, focusing on four families impacting human health. Triplicate libraries were prepared for each sample and each kit. All three kits allowed the characterization of a variety of viral genera. In sewage samples, a large number of long contigs was obtained allowing a precise identification of more than 35 strains. In shellfish samples, long contigs were rarer but allowed the identification of one human astrovirus and one norovirus strains. Of the tested kits, one displayed lower variation between replicates, allowed to sequence a higher diversity of viruses from the four families of interest and yielded a higher number of nearly-whole genomes
Identification de métabolites microalgaux avec effets cytotoxiques, inflammatoires ou anti-inflammatoires, via des modèles cellulaires de peau humaine
No full textMicroalgae present a dual nature: while certain species are toxic or harmful, posing risks to human health, the environment, and socio-economic activities, others are of interest for their ability to produce metabolites with promising industrial potential. The toxic dinoflagellates Ostreopsis cf. ovata and Vulcanodinium rugosum can cause skin irritation during blooms, whereas Dunaliella salina, Tetraselmis suecica, and Cylindrotheca fusiformis exhibit anti-inflammatory and antioxidant properties beneficial to skin care. This PhD project combined analytical chemistry and cellular bioassays to identify the metabolites responsible for the reported cutaneous effects. Extracts of O. cf. ovata displayed strong cytotoxicity correlated with the presence of ovatoxins (OVTXs), and the five purified analogues (OVTX-a to -e) showed similar toxicity profiles.Il existe une dualité dans l’étude des microalgues. Certaines espèces, toxiques ou nuisibles, représentent un risque majeur pour la santé humaine, l’environnement et les activités socio-économiques, tandis que d’autres, valorisables, produisent des métabolites à fort potentiel industriel. Les dinoflagellés toxiques Ostreopsis cf. ovata et Vulcanodinium rugosum peuvent provoquer des irritations cutanées lors de leurs efflorescences tandis que Dunaliella salina, Tetraselmis suecica et Cylindrotheca fusiformis présentent des propriétés anti-inflammatoires et antioxydantes pour la peau. En combinant des approches de chimie analytique et de bioessais cellulaires, ce projet de thèse a cherché à identifier les métabolites impliqués dans ces effets. Les extraits d’O. cf. ovata ont révélé une forte cytotoxicité, corrélée à la présence d’ovatoxines (OVTX), et les cinq analogues (OVTX-a à -e) purifiés ont montré une toxicité similaire. Pour V. rugosum, nous avons montré que la portimine A induit une forte cytotoxicité et inflammation sur les kératinocytes humains via l’activation de l’inflammasome NLRP1 par un stress ribotoxique, confirmant sa possible implication dans une épidémie de lésions cutanées de pêcheurs sénégalais. Enfin, un fractionnement bio-guidé des microalgues valorisables, associé à une déréplication par réseaux moléculaires, a permis d’identifier, chez C. fusiformis, des acides aminés Nacylés susceptibles de contribuer aux effets anti-inflammatoires observés. Ces travaux apportent de nouvelles données pour la caractérisation du risque cutané lié aux phycotoxines et ouvrent des perspectives sur le potentiel cosmétique des métabolites produits par C. fusiformi
Workshop on Participatory Modelling (WKParticipatoryModelling; outputs from 2024 meeting).
No full textThe Workshop on Participatory Modelling (WKParticipatoryModelling) was convened to advance the integration of participatory approaches into ICES science and advice. Its terms of reference included reviewing past participatory modelling experiences, identifying where its application could improve ICES processes, and developing a structured framework for future implementation. The workshop addressed three questions: (1) How has participatory modelling been used inside and outside ICES, and what lessons can be drawn? (2) In which areas could ICES benefit from participatory modelling? (3) How to build a robust participatory modelling framework compatible with ICES workflows? The workshop found that while participatory modelling improves the credibility, relevance, and acceptance of scientific outputs, its application within ICES is inconsistent. Some successes were achieved in integrated ecosystem assessment (IEA) groups and more specifically in the Workshop on an Ecosystem Based Approach to Fishery Management for the Irish Sea (WKIRISH) expert group. However, major challenges remain, including a lack of structured methods, limited training, and difficulties in balancing empirical science with experiential stakeholder knowledge. The group identified high-priority areas for participatory modelling, including mixed-fisheries management, integrated ecosystem assessments, marine spatial planning, biodiversity conservation, and climate impact assessments. Participatory modelling is especially relevant when stakes are high, uncertainties are high, multiple views or interests are conflicting, and when models represent the behaviour of human groups. A draft framework was developed to guide participatory modelling in ICES. It emphasizes clear justification for participation, rigorous stakeholder selection, co-development of models, robust facilitation, transparent communication, and systematic monitoring and evaluation. The framework is modular to allow adaptation across different projects and sectors. A practical method to guide, assess, and report participatory engagement is also provided as annex to the report. Future work priorities include testing and developing the framework in selected case studies, training ICES scientists and stakeholders in participatory techniques, showcasing participatory modelling at ICES Annual Science Conference, and embedding participatory modelling practices into standard ICES advisory processes. The long-term goal is to institutionalize participatory modelling to enhance trust, transparency, and the real-world applicability of ICES science and advice
Resilient coral in New Caledonia
No full textWith climate change comes acidification and warming of the oceans, and if this increases, the consequences for coral reefs could be dramatic
How marine heatwaves are reshaping phytoplankton in the Northeast Pacific
No full textIn 2015 and 2019, the Northeast Pacific has undergone significant heatwave events that strongly disrupted marine ecosystems functioning and services. Here we use the data collected by the Continuous Plankton Recorder (CPR) survey to investigate the changes in summer phytoplankton abundance and morphology and show an increase in prolate (i.e., elongated) taxa during heatwave events, in response to warmer temperatures and declining nitrate. We also investigate the impacts of the morphological shifts on the carbon cycle and show that warmer periods were dominated by prolate cells with high carbon content, whereas cooler periods were dominated by oblate (i.e., flattened) cells with low carbon content. By altering community composition and the overall cells sinking velocity, these morphological shifts likely impacted the carbon cycle, as they were correlated with changes in surface chlorophyll a and particulate organic carbon concentrations