PhD proposal - ADR models & Biogeography

✦ Context

PhD Thesis Project – PEPR BRIDGES, Mediterranean Institute of Oceanography (MIO)
Application submitted 2025 – Hosting: ECOMAD team (MIO, Aix-Marseille University)
Supervision: Dr. Vincent Rossi (CNRS-MIO), Pr. Valeriano Parravicini (EPHE/CRIOBE), Dr. Vincent Calcagno (INRAE-ISA)

I planned to design a mechanistic modelling PhD project that uses advection-diffusion-reaction (ADR) models to quantify how mid-to-high trophic level marine vertebrates (fish, turtles, seabirds) respond to key oceanic structures (thermal fronts, Lagrangian coherent structures, eddies, currents, bathymetry) in the South-West Indian Ocean (SWIO). The central question is: “How do marine organisms respond differently to oceanic structures in the SWIO, and what are the implications of these species-specific sensitivities for regional connectivity patterns and population persistence under current and future climate conditions?”

The thesis title is:
“From reef to open ocean: multi-vertebrate responses to oceanic structures in the SWIO and their connectivity implications under climate change – a mechanistic approach with ADR modelling”

✦ Tools & Skills

ADR / PDE modelling Biophysical connectivity Lagrangian analysis (FSLE) Ocean front detection CMIP6 / CROCO downscaling Satellite telemetry & acoustic tagging Spatio-temporal scales (1:50 km, monthly-seasonal) Spatial connectivity matrices FAIR open-source code release Multi-taxa comparative framework Climate velocity & scenario projections

✦ Key Contributions (Thesis Proposal)

• Novel integration of ocean front gradients as an **active advection term** in a lightweight ADR model (beyond correlative or complex end-to-end models)
• Multi-taxa framework spanning contrasting ecological strategies: reef vs. pelagic fish (Giant trevally, blacksaddled coral grouper), herbivorous/spongivorous turtles (green & hawksbill), and seabirds (sooty tern)
• High-resolution data fusion: WINDS-M currents (1/50°), NOMAD fronts/FSLE (1 km), Copernicus SST, GEBCO bathymetry, CMIP6/CESM-LENS + CROCO downscaling (SSP2-4.5 / SSP5-8.5, 2050 & 2100)
• Direct support to BRIDGES Challenges 1 (INNOVER), 2 (MODÉLISER) and 3 (ANTICIPER) through realistic socio-ecological modelling, climate redistribution simulations, and FAIR-compliant code release
• Four-phase 36-month timetable: data preprocessing & sensitivity tests (M1–M6), ADR model implementation (M6–M12), scenario simulations (M12–M24), comparative analyses & conservation implications (M24–M36)
• Expected outputs: spatial connectivity matrices, dynamic distribution maps, species sensitivity indices, and policy-ready vulnerability assessments for resilient MPA networks

✦ Outputs & Links

📄 Full research proposal (PDF) 🏛️ Hosting lab – Mediterranean Institute of Oceanography (MIO) 🌊 PEPR BRIDGES programme

Note: This PhD proposal was submitted in February 2026 for the BRIDGES “Grappes de thèse” PhD program. Full scientific description, methods, timetable, risks/mitigations and 24 bibliographical references are detailed in the attached application file.