Advisory Councils: What are the impacts of marine wind energy?

The technological development that during the last decade has increased the profitability of especially offshore wind farms have rocketed the expansion of marine wind energy, and thus the marine activities that follow. With this in mind, the Pelagic Advisory Council, of which European Fishmeal is a member, the North Sea Advisory Council, and the North-Western Waters Advisory Council, ask for independent scientific advice on how marine wind energy affects commercial fish stocks.

The offshore wind energy industry has expanded rapidly during the last decade. In Denmark alone, the number of offshore wind turbines has grown from 314 in 2009 to 558 in 2019, an increase of 78%. Today there are 5,047 grid-connected offshore wind turbines across Europe with an average distance to shore of 59km and an average water depth of 33m, and with a total height of up to 260m.

The rapid and exponential expansion of offshore wind turbines means that the need for sound, reliable and independent research on the environmental impact has increased correspondingly.

Fisheries and offshore wind energy developments coexisting is vital for both food and energy production in the future. However, the understanding of interactions and impacts of these rapidly expanding offshore wind developments on fisheries remains limited.

” What the joint advisory councils call for is, that research and knowledge on the impacts of offshore wind farms on the marine environment keep up with the rapid development. Because if we do not know how this expansion affects the marine life and the ecosystem, we can end up doing irrevocable damage” says Søren Anker Pedersen, Chief Biologist at European Fishmeal.

The NWWAC, NSAC and PELAC have joined forces in a joint Focus Group on impacts from offshore wind farms, to formulate the specific research needs and advice deliverables for a non-recurrent request to from the International Council for the Exploration of the Sea (ICES).

All three AC’s would benefit from ICES advice on the following general research questions: The full advice from the advisory councils can be read here. 

• What is the impact of habitat change on larval, juvenile, and adult stages of fish and invertebrate species in a variety of ways of habitat changes associated with offshore wind energy facility construction and operation,( for example loss of hard bottom and sand wave habitats due to sedimentation and scouring, addition of high-relief habitat around turbines, redistribution/displacement of important spawning, nursery, and foraging habitats?
• What are the impacts of changes in sea surface and seafloor circulation patterns associated with the development of offshore wind energy facilities on patterns of larval drift and settlement, for example in cod, as well as the cumulative impacts of several wind parks situated closely together and of all marine activity in the geographical vicinity considered together?
• What are the impacts of changes on upwelling events and productivity cycles that drive fish production, turbidity and sedimentation processes that influence species assemblage structure and trophic interactions?
• What are the behavioural and physical effects related to construction activities of offshore wind energy developments, for example high impulse activities such as pile-driving and seismic exploration, on larval/adult life stages of commercially exploited fish and invertebrate species?
• What is the impact of electromagnetic energy leaking from offshore wind installation, including transmission cables on the seafloor, on elasmobranch species, which use electromagnetic fields to navigate and hunt for food?
• Is there an increased risk regarding the introduction of invasive species both during both development and construction phase of offshore wind energy developments?
• Does increased noise and vibration associated with the operation of windfarm developments and increased boat traffic result in increased larval mortality for commercially exploited fish and invertebrate species, displacement of or interruption to migration patterns and reproductive behaviours, alteration of species distributions, and injury or mortality of fish?
• To what extent have accumulations of offshore wind farm developments and other noise sources been taken into consideration in existing research, and within EIAs? When considering existing environmental impact assessments (EIAs) carried out prior to offshore wind farm developments, what parameters are not addressed that would be relevant to be included to determine the impact of the surveys on (the major) commercially exploited stocks within an ecosystem context for example via model-based approaches as identified by ICES WGODF?
• What are the adverse responses (life cycle, biological functions) of larval, juvenile, and adult stages of fish and invertebrate species to potential pollution from wind turbine developments (for example structures, paints, sacrificial anodes)? Are there any recommendations to avoid and reduce these potential impacts?
• What are the cumulate impacts relating to both the upscaling of existing wind farms and the colocation of several wind farms in the same geographical area on the environment and natural resources, and specifically on spawning grounds?
• What are the impacts on lobster and crab populations in shallower waters close inshore where cable laying, including associated seismic surveys related to offshore wind farms, takes place?