Thesis in Marine spatial planning (M/F)

Deadline for applications: 20/04/2026 Who are we ? The Joint Research Unit (UMR) "Dynamics and Sustainability of Ecosystems: from Source to Ocean" (DECOD) brings together researchers, engineers, and technicians from Ifremer, INRAE, and Institut Agro Rennes-Angers, with laboratories located in Nantes, Lorient, Brest, and Rennes. DECOD's activities focus on analyzing ecological and evolutionary processes in aquatic environments and their interfaces, from headwaters to the ocean, assessing ecosystem status, and developing scenarios for their future evolution. The PhD project will be conducted within the Ecology and Modelling for Fisheries (EMH) laboratory of the HALGO unit, part of the DECOD Joint Research Unit. Members of the laboratory develop knowledge and methods supporting the ecosystem-based approach to fisheries, with a particular focus on integrated ecosystem assessment. In this context, the team contributes to defining the conditions for the sustainable exploitation of marine resources and their ecosystems. The PhD supervisory team brings together complementary expertise in spatial modelling, marine ecology, fisheries science, and maritime spatial planning. Internal collaborations within Ifremer span several research units, ensuring a stimulating and intellectually rich environment for the PhD candidate. This work builds on a well-established scientific foundation. Recent milestones include an internal workshop (PANCEC) informing the WGEAWESS for the development of integrated ecosystem assessment, the WKTRADE2 workshop on trade-offs between marine habitats and fisheries in European seas, research on the conservation of Vulnerable Marine Ecosystems (VMEs) in the Mediterranean (Millot, 2025), and the prioritization of Marine Protected Areas and offshore wind farms on the Grande Vasière (Boussarie et al., 2023). The results will be submitted to ICES working groups (e.g. WGMPCZM - marine spatial planning and conservation zones), providing an international dimension to the scientific outputs. At the national level, long-standing partnerships with the fishing sector represent a major asset: Producer Organisations (POs) from the Bay of Biscay, the National Committee for Marine Fisheries and Marine Farming (CNPMEM) and its local branchs, the French Biodiversity Agency (OFB), the Directorate of Water and Biodiversity, French Ministry for Ecological Transition (DEB), and the Directorate General for Maritime Affairs, Fisheries and Aquaculture (DGAMPA) are involved in co-construction workshops with stakeholders. The PhD candidate will join a dynamic research unit, DECOD, and will benefit from Ifremer's high-performance computing infrastructure, particularly Datarmor, for spatial analyses and algorithmic optimisation. Access to existing marine and fisheries databases (spatial layers, fleet data) is included in the working environment. What is the topic of the thesis? This PhD project takes place in a context of increasing pressures on marine spaces, driven both by the development of human activities (e.g. marine renewable energy, fisheries, transport, recreation) and by climate change. The need for energy transition and ambitious biodiversity conservation targets, such as the international "30x30" goal further intensifies these challenges, notably by accelerating the deployment of offshore wind farms, while imposing new constraints on existing uses, particularly fisheries. In this context, the PhD aims to develop integrated approaches to maritime spatial planning that can reconcile these sometimes-conflicting objectives. It will focus on designing decision-support tools capable of accounting for ecosystem complexity (taxonomic and functional biodiversity, ecosystem services, vulnerable habitats and species), interactions and conflicts among uses, as well as human, economic, and social dimensions (equity among stakeholders, acceptability of measures). Particular attention will be given to the management of uncertainties and to the integration of temporal dynamics, including feedbacks between management measures, ecosystem responses, and adaptations of human activities. The work will focus on the Bay of Biscay as a case study, a well-documented area, representative of current challenges, in order to develop forward-looking scenarios and operational spatial management strategies, co-constructed in close collaboration with stakeholders. What will your mission and activities be? Phase 1: Equitable spatial planning

• Collection, harmonisation, and integration of spatial data (ecological and human uses) from public and institutional databases.
• Enrichment of datasets through the integration of new conservation criteria (ecologically significant areas, sensitive habitats, existing protection networks).
• Collaboration with experts and stakeholders (workshops) to validate data and define objectives, constraints, weighting, and uncertainties.

Phase 2: Uncertainty analysis and transparency

• Assessment of the sensitivity of results to input data and parameters (quality, resolution, relative weights).
• Development of approaches to characterize and reduce biases (uncertainty analyses, robustness testing).
• Integration of multi-resolution data, with particular attention to coastal areas.

Phase 3: Spatial transition pathways and scenarios

• Development of forward-looking scenarios integrating climate change, ecosystem dynamics, and adaptation of human activities (notably fisheries).
• Implementation of participatory approaches to co-construct management pathways.
• Analysis of the effects of management measures and feedbacks between ecosystems and human uses, comparing static and adaptive spatial planning approaches.

Key Words : Marine spatial planning, scenarios, decision-support tools, marine protected areas, participatory approaches, robustness, equity, conservation-exploitation trade-off. How are your activities organised ? Computer-based work (data analysis, optimization, GIS, coding)

• Participation in meetings (scientific advisory boards, research committees, etc.)
• Writing of publications and reports
• Collaboration and exchanges with colleagues and stakeholders

The work will take place mainly in France, within the EMH laboratory in Nantes. Participation in working groups and at least one international conference will require the PhD candidate to travel during the three years of the doctoral program. What are your benefits?

• We have a teleworking agreement and our staff have 12 comp time days (after 6 months' seniority) and supra statutory leave.
• We allocate a significant budget to developing skills, through individual or collective training actions.
• We have a CSR policy inspired by the purposes of the institute (sustainable mobility allowance, etc.)

How to apply? Your application file must include in a pdf file :

• a curriculum vitae
• a covering letter
• a reference letter
• an academic transcript (Bachelor + Master 1 and first semester Master 2)

The deadline for applications is 20/04/2026. Nevertheless, we strongly urge you to let us know as soon as possible of your intention to apply, by contacting the subject supervisors:

In parallel, please submit your application to the doctoral school : 20/04/2026 Doctoral students' contracts will start as of October 5th, 2026, subject to the submission of administrative documents authorizing Ifremer to recruit the doctoral student (certificate of completion of the Master 2 or engineering degree + visa for foreign doctoral students outside the EU). What are the next steps? Please modify the steps as needed;

• Review of your application
• In-person or video conference interview
• Interview before a doctoral school committee, with representatives from the doctoral school and Ifremer
• Approval of your application by the doctoral school council

Who are you ? - Master in fishery sciences or numerical ecology, You have the following skills, knowledge and experience :

• Fisheries ecology
• Computational/ecological modelling
• Statistics
• Modelling
• Programming
• Interest in participatory science
• English (spoken and written)

You have the following qualities :

• Intellectual curiosity
• Rigor and organizational skills
• Ability to synthetize complex information
• Tenacity and perseverance
• Collaborative and interdisciplinary mindset
• Initiative-taking
• Open-minded and constructive