Freshwater ecosystems are amongst the most threatened ecosystems on earth and the threats they face also extend to the migratory fish using them. This is likely due to a multitude of stressors and a sequential dependency of migratory fish on the typically narrow and linearly shaped river systems without spatial alternatives. Not only are they caught for consumption, blocked by barriers (such as weirs, dams, and locks), but they are also confronted with an altered underwater riverscape of artificial light at night and traffic noise from boats, nearby roads and the daily rhythm of human activities.

We know there are problems for fish during their migration, but we do not know to which extent they are determined by light and sound conditions, or to which extent smart solutions may exist to reduce problems at migratory bottlenecks. We also do not know how typical diurnal or nocturnal migrants respond to artificial light at bifurcations or river stretches, or how they react to the fluctuations of sound level and spectra during passages through cities or under bridges. At Leiden University, we study the underwater light- and soundscapes in Dutch river systems, and we test impact of field conditions in the laboratory, using the newly built MIGRADROME, a 7 meter long swim tunnel, in which we can manipulate light and sound conditions, as well as the speed and gradient of the water velocity.

We are looking for a talented and motivated PhD candidate that will explore the combined effects of light and noise pollution on migratory fish in outdoor and indoor conditions. This PhD-project is part of a large consortium funded by the EU-HORIZON-project AquaPLAN, and follows up on PhD-projects on the effects of light pollution on the biological clock of migratory fish (within the NWO-NWA-funded BIOCLOCK-project) and the effects of vessel noise on swimming behaviour of migratory fish (EU-HORIZON-project SATURN).

Key tasks

• Design and execute sampling efforts on environmental light and sound conditions in combination with presence and behaviour of local and migratory fish communities
• Conduct controlled exposure experiments in the MIGRADROME to test combined effects of multiple stressors on migratory tendencies of various fish species

Selection Criteria

• An MSc degree in behavioural biology, animal ecology, animal physiology, environmental sciences, conservation biology, or a related discipline (preferred experience with fish and aquatic systems)
• Passion for fieldwork in rural wetlands and urban river systems
• Affinity to perform a combination of field and laboratory work, with observational and experimental studies
• Strong quantitative skills (including statistical analyses in R)
• Team player and collaborative attitude
• Proficiency in spoken and written English
• Ability and affinity to disseminate scientific data through peer-reviewed publications and public outreach to a variety of audiences and relevant stakeholders

Terms of employment
We offer a 1-year position with the possibility of extension to 4 years based on performance and following the pay scale P in accordance with the Collective Labour Agreement for Dutch Universities. Salary ranges from € 2,770.- gross per month in the first year to € 3,539.- gross per month in the fourth year based on a full-time position. Leiden University offers an attractive benefits package with additional holiday (8%) and end-of-year bonuses (8.3 %), training and career development. Our individual choices model gives you some freedom to assemble your own set of terms and conditions. For international spouses we have set up a dual career programme. Candidates from outside the Netherlands may be eligible for a substantial tax break. Leiden University is strongly committed to diversity within its community and especially welcomes applications from members of underrepresented groups.

Universiteit Leiden

Faculty of Science, Leiden
The Faculty of Science is a world-class faculty where staff and students work together in a dynamic international environment. It is a faculty where personal and academic development are top priorities. Our people are committed to expand fundamental knowledge by curiosity and to look beyond the borders of their own discipline. Their aim is to benefit science, and to make a contribution to addressing the major societal challenges of the future. The research carried out at the Faculty of Science is very diverse, ranging from mathematics, information science, astronomy, physics, chemistry and bio-pharmaceutical sciences to biology and environmental sciences. The research activities are organized in eight institutes. These institutes offer eight bachelor's and twelve master's programs. The faculty has grown strongly in recent years and now has almost 2,800 staff and over 6,000 students. We are located at the heart of Leiden's Bio Science Park, one of Europe's biggest science parks, where university and business life come together. For more information, see www.universiteitleiden.nl/en/science and www.universiteitleiden.nl/en/working-at

Institute of Biology, Leiden University
The research within the Institute of Biology Leiden (IBL) aims to work on the science base of biodiversity and health, which is reflected in our leading principle 'Harnessing Biodiversity for Health'. We perform innovative curiosity-driven research to answer fundamental questions, and solutions-driven research to help solving major societal challenges. The latter include protecting biodiversity, creating sustainable biotechnology and agriculture, and improving conditions for good human health. We focus on four Research Themes: Bioactive Molecules, Host-Microbe Interactions, Development & Disease and Evolution & Biodiversity. IBL offers an exciting, internationally oriented, and inclusive place to work and study. For more information about IBL see: www.universiteitleiden.nl/en/science/biology.