Fish
The Wozep fish research focuses primarily on the acquisition of more knowledge about the strength and possible effects of electromagnetic fields around power cables. Various related projects are looking at the influence of noise (from both piling and operations) on fish behaviour.
Many different species of fish (approximately 145), including sharks and rays, are found in the Dutch section of the North Sea.
The construction and presence of wind farms can affect fish in different ways. For example, fish can be disturbed by the construction of the park (noise disturbance) or they can be attracted by the presence of hard substrate (in the form of the turbine and scour protection). Some species, such as sharks and rays, can be affected by the electromagnetic fields produced by the power cables. In addition, fishing is not allowed at present in wind farms, and this could have a positive effect on local fish stocks.
To minimise the impact on fish (and marine mammals) during the construction phase, a sound standard, a slow-start procedure and acoustic deterrents will be used to induce these species to leave the piling area and prevent effects at the population level.
After the construction phase, wind farms enter the operational phase during which they produce electricity (when the wind speed is high enough). Underwater cables, both inside the wind farms and between the wind farms and the mainland, are used to transport the electricity. Those cables produce electromagnetic fields that some organisms can sense. They include electro-sensitive fish (such as sharks and rays), as well as fish that are sensitive to the magnetic field (such as sturgeon, sea lamprey, plaice, sole, etc.). An electromagnetic field can have an impact on things like the behaviour, migration and reproduction of a species, as well as foraging. The extent of this impact is still not clear.
Ongoing research
A pilot (pdf, 8.7 MB) project was conducted in 2019 to look at the effects of electromagnetic fields [link to report] as a follow-up to an earlier desk study. A follow-up study - ElasmoPower - has been ungoing since 2020 looking at the impact of electromagnetic fields on, among other fish, sharks and rays. ElasmoPower is a research project of Wageningen University & Research, in collaboration with energy network manager TenneT, Naturalis, Witteveen + Bos, Rijkswaterstaat (Wozep) and The North Sea Foundation. The research is co-funded by the Netherlands Organisation for Scientific Research (NWO).
In addition, Wozep has joined the ‘Forage Fish’ project, which is conducting research into (among other things) the distribution of sand eels. Top predators such as seabirds and sea mammals are an important focus of Wozep research. Previous studies have shown that top predators depend on forage fish such as herring, sprat and sand eel. In turn, forage fish depend on plankton production. However, there are still knowledge gaps in our understanding of how these three factors interact. The Forage Fish project was set up to fill these knowledge gaps.
List with reports on completed studies
****https://www.nwo.nl/en/research-and-results/research-projects/i/09/35909.html