PhD modelling impact of changes in North Sea benthic habitats key fish species

PhD candidate for modelling the impact of changes in North Sea benthic habitats on key fish species

NIOZ Royal Netherlands Institute for Sea Research is the National Oceanographic Institution of the Netherlands.

The Department of Coastal Systems (COS – location Texel) of NIOZ is looking for a highly motivated and proactive PhD candidate to carry out analyses with fish population models and to build connections to lower trophic level models.

NWO‑NIOZ Royal Netherlands Institute for Sea Research is the Dutch national oceanographic institute and principally performs academically excellent multidisciplinary, fundamental, and frontier‑applied marine research addressing important scientific and societal questions pertinent to the functioning of the ocean and seas. NIOZ includes the National Marine research Facilities (NMF) department that operates a fleet of research vessels and the national pool of large seagoing equipment, and supports excellence in multidisciplinary marine research, education, and policy development.

As part of the Energy Transition, further expansion of offshore renewable energy is expected in the North Sea in the next decades. This will likely affect the marine ecosystem and fisheries, but how and to what extent is an open question. To address this, Rijkswaterstaat initiated the MONS project. In addition to an extensive observational program, the project will bring together a suite of existing models, ranging from spatially explicit lower trophic level models through fish population models to fisheries management models.

These will be connected to work together for investigating effects of large‑scale renewable energy installations and climate change on the marine ecosystem and fisheries of the North Sea. In this project, NIOZ works together with Wageningen Marine Research (WMR) and Deltares to address these major issues.

With the expansion of offshore wind farms (OWF) in the North Sea substantial areas of hard substrate are added to the ecosystem, which may present opportunities and challenges for marine organisms, but it is unclear whether such effects would be mostly positive or negative. Introduced hard substrates may attract fish species by providing food or shelter (e.g. gadoids) but also deter species that prefer a sandy bottom.

At the same time, productivity of the benthic (invertebrate) community may be affected (increased) through introduction of hard substrate that functions as settlement habitat. These unknowns and the quantitative impact of these processes are addressed by this PhD project that aims to elucidate the immediate and long‑term impact of introduced hard substrate on the demersal food web structure and dynamics.

In this project you will focus on connecting the dynamics of upper and lower trophic levels, specifically exploring the populations of Atlantic cod (Gadus morhua) and plaice (Pleuronectes platessa) in relation to changes in their major prey species. You will use existing population models for fish and contribute to developing and applying these in a larger food web context. A key innovation will be creating mechanistic and seamless links between models of fish population dynamics and lower trophic level models that are often constructed at different dimensions and that use different units.

Your project is part of a larger MONS programme and there will be many occasions and opportunities for close collaboration with other project members within MONS as well as other NIOZ researchers working on related projects. You are expected to produce a PhD thesis and publish your research results in peer‑reviewed scientific journals, and to present your work at international conferences and MONS meetings.

You will be integrated within an active group of students and PhD candidates, as well as researchers within the COS department. The position aims to start on 1 September 2026.

The Department of COS studies integral coastal ecosystems and their populations of fish, birds, and other marine animals in the North and Wadden Seas as well as on a global scale. The department focuses on key physical, chemical and biological…