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

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.

ROYAL NIOZ 

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. 

THE PROJECT

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.

THE POSITION

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 
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 focusses on key physical, chemical and biological processes that determine the productivity and the ecological functioning of coastal areas. The coastal system is studied as a unity by considering the interrelations between the key compartments of the ecosystem (water, sediment, microalgae, macrozoobenthos, parasites, fish, marine mammals and birds).

THE CANDIDATE 

• You have an MSc in a relevant discipline, and experience with mathematical modelling, population dynamic analyses, and/or theoretical (ecological) methods

• Programming experience is an advantage, for example with Python, R, C++ or Matlab.

• As a scholar, you are well-organized, willing to learn and can adapt to developing insights

• You are highly self-motivated, and able to work both independently and as part of a team

• You have excellent written and oral communication skills (in English)

THE CONDITIONS 

• Employment of this full-time position at Royal NIOZ is by NWO-I, for a total duration of 4 years.  You start with an appointment for the duration of 1 year, that, after a positive evaluation in the 9th month (Go-No go), will be extended to the full period of 4 years.

• Salary compliant with scales for PhD candidate (OIOs) CAO-WVOI (Collective Labour Agreement for Dutch Research Institutes). 

• An appointment at NIOZ as a PhD candidate means working and learning simultaneously conform the NIOZ PhD policy.  

• 338 annualized holiday hours for a full-time 40-hour work week.

• Pension scheme via ABP, 8% holiday allowance and a year-end bonus of 8.33%. 

• 2nd class public transportation travel is reimbursed 100%.

• Employment benefits plan to exchange a portion of your salary for days off or vice versa, or can be used to purchase a bicycle with tax benefits.

• We offer relocation expenses for employees coming from abroad and support with finding accommodation.

NIOZ focuses on being a transparent institute with a healthy working climate and an inclusive culture, where people from diverse backgrounds and gender bring their talents and further develop these talents. We aim for inclusive decision-making processes and expect our leadership to show visible commitment, awareness of bias, and cultural intelligence.

MORE INFORMATION
The deadline for applications is 26 June 2026. Interviews are planned for Tuesday 7 July 2026 with a possible second round in August.

For additional information about this vacancy, please contact Dr. Anieke van Leeuwen. For additional information about the procedure, please send an e-mail to working@nioz.nl.