Researcher In Ecology Modelisation H/F Ifremer

Deadline for applications : 10/02/2026

The Joint Research Unit (UMR) "Dynamics and Sustainability of Ecosystems: from the Source to the Ocean" (DECOD) brings together researchers, engineers and technicians from Ifremer, INRAe and the Institut Agro Rennes-Angers with laboratories in Nantes, Lorient, Brest and Rennes. DECOD's activities focus on the analysis of ecological and evolutionary processes at work in aquatic environments and their interfaces, from the source to the ocean, on the assessment of the state of ecosystems and on the construction of scenarios for these ecosystems.

The challenge of the Grand Ouest Fisheries Unit (HALGO), an Ifremer component of the DECOD joint research unit, is to develop knowledge and methods for the ecosystem approach to fisheries, and in particular for the integrated assessment of ecosystems. The unit contributes to the definition of the conditions for the sustainable exploitation of fisheries resources and ecosystems. The Fisheries Technologies and Biology (LTBH) laboratory contributes more particularly to the assessment and reduction of the environmental impacts of fishing gear.

Previous projects from our lab have enabled, on one hand, the development of a 3D simulation environment for fishing gear (FineLab) and on the other hand, to collect fine-scale data on fish behavior inside trawls (Projects : ESCAPE, Game of Trawls, MarineBeacon, etc.).

The position is placed within the Laboratory of Fisheries Technologies and Biology.

What will your mission BE?

The objective of this position is to develop an Individual-Based Modelling (IBM) framework to study fish-gear interactions. This work will go beyond traditional modelling approaches as it enables us to manipulate internal and external variables. IBM models are powerful because they can flexibly represent observed natural processes, such as swimming and escape behaviours. They can study the link between individual behaviours and the resulting collective dynamics. This quantitative approach could enable us to estimate the main parameters of gear selectivity, such as the L50 or the selection range, depending on the environment, the species present, and their specific behaviours, which has never been undertaken so far.

What will your activities BE?

Behaviour modelling will partly be informed by the results obtained in other ESCAPE project work packages in which several behavioural archetypes are currently being defined (https://www.francefilierepeche.fr/projets/escape-etude-echappement-poissons-engins-peche). The position's main challenge will be integrating this knowledge and data into an IBM model.

You will improve the existing Qt C++ code to implement behavioural rules and to optimise computing time. Metrics will be defined to compare modelling and experimental local results. The behavioural rule parameters will be optimised to minimise objective functions based on modelling and experimental overall results.

This work should be promoted through at least one A-level scientific publication.