PhD : Effects of climate change on the productivity of sardine in the English Channel (M/F)

Ifremer undertakes research missions, offers expert advice and acts as a funding agency.
Ifremer performs targeted applied research to address the questions posed by society (climate change effects, marine biodiversity, pollution prevention, seafood quality etc.). Results include scientific knowledge, technological innovations, and systems for ocean observation and exploration. Partnerships may be public, private or a combination of the two.
Ifremer works in a network with the French scientific community, also collaborating with international partner organizations, in the frame of several national and international projects, including contractual activities.
The Channel & North Sea Fisheries Research Unit (Unité Halieutique Manche Mer du Nord, HMMN) is investigating the dynamics of marine fisheries, ecosystems and biodiversity, subject to the pressure of fisheries and other human activities in a global change context, as well as evaluating management strategies to mitigate the impact of these pressures.
Summary
Small pelagic fish are a valuable source of nutriments, particularly omega 3 fatty acids, which are essential for human health. These fish also play a pivotal role within marine ecosystems, representing an important food source to larger predators and at the same time mitigating the dynamics of lower trophic levels.
Sardine is a species of commercial interest for coastal vessels fishing in the English Channel, particularly since the re-opening of the fishery in the Bay of Seine. This interest is likely to grow in the future as a result of the expected (climate-driven) northwards latitudinal shift of sardine habitats. However, the biology and ecology of English Channel sardine are still poorly understood, and this PhD thesis project will bring new information on the mechanisms driving both recruitment and spawners’ condition, which will input evaluation and projection models. This PhD thesis aims at understanding past dynamics and anticipating the future trajectories of English Channel productivity, in a global change context. The project has three overarching objectives : (1) To gain knowledge on the connectivity and survival of early life stages ; (2) To decypher the environmental and population dynamics mechanisms influencing spawners’ condition ; (3) To project productivity trajectories under global change.
You will shed light on the spatio-temporal dynamics of English Channel spawners, eggs and larvae, which are currently poorly understood. To that purpose, you will account for the productivity of pelagic habitats, from spawning migrations to early-life stages, as well as the pressure exerted by predators and intrinsic factors. You will also perform a meta-analysis of fatty acids and prey composition data available from the English Channel, the Bay of Biscay and the Mediterranean Sea basins in relation to environmental factors. This analysis will feed in an integrative approach aiming at better understanding sardine productivity across all French metropolitan marine basins. The model that will be developed (e.g., SEAPODYM, DEB-IBM, or others, depending on available data) will be applied to simulate the effects on future productivity trajectories of fisheries management strategies under global change.
Key words
Sardine, English Channel, connectivity, spatio-temporal dynamics, ichthyoplankton, recruitment, spawning migrations, essential fatty acids, trophic ecology, modelling
Specific working conditions
– Full time
– Travelling in France and abroad
– Sea cruises
– Phd is a real opportunity to work on Ifremer’s scientific and technological priority themes. It entitle the holder to a gross monthly salary of 2300 euros gross for a period of 3 years, which cannot be combined with other scholarships.

Profil recherché
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Master’s degree in quantitative ecology or marine ecology. The candidate will have a numerical profile, strong expertise in statistics and modelling, and the ability to program (e.g., R, SAS, MATLAB, Python).

Informations utiles
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– Localisation Boulogne-sur-Mer – 62, France – zone de déplacement : internationale
– Contrat CDD – 3 ans
– Salaire 2300,00 EUR par mois
– Niveau de qualification Ingénieur/Cadre/Bac +5
– Expérience – 1 an
– Modalités de travail Temps complet
– Fonction Bureau d’Etudes/R&D/BTP archi/conception, Ingénierie – Chimie/Pharmacie/Bio.
– Secteur Secteur Energie/Environnement, Service public autres
– Télétravail Occasionnel
How to apply for this position
Your application file must include:
– a curriculum vitae
– a covering letter
– a reference letter
– an academic transcript (Bachelor + Master 1 and first semester Master 2)
Your application must be compiled into 2 PDF files, up to 3 MB for each file.
The deadline for applications is April 17th 2025. Nevertheless, we strongly urge you to let us know as soon as possible of your intention to apply, by contacting the subject supervisor: Paul MARCHAL
Doctoral students’ contracts will start as of October 6th, 2025, 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).

Qui sommes nous ?
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