Effects of offshore wind farms on marine wildlife

Marine management plans over the world express high expectations to the development of offshore wind energy. This would obviously contribute to renewable energy production, but potential conflicts with other usages of the marine landscape, as well as conservation interests, are evident. The present study synthesizes the current state of understanding on the effects of offshore wind farms on marine wildlife, in order to identify general versus local conclusions in published studies. The results were translated into a generalized impact assessment for coastal waters in Sweden, which covers a range of salinity conditions from marine to nearly fresh waters. Hence, the conclusions are potentially applicable to marine planning situations in various aquatic ecosystems. The assessment considered impact with respect to temporal and spatial extent of the pressure, effect within each ecosystem component, and level of certainty. Research on the environmental effects of offshore wind farms has gone through a rapid maturation and learning process, with the bulk of knowledge being developed within the past ten years. The studies showed a high level of consensus with respect to the construction phase, indicating that potential impacts on marine life should be carefully considered in marine spatial planning. Potential impacts during the operational phase were more locally variable, and could be either negative or positive depending on biological conditions as well as prevailing management goals. There was paucity in studies on cumulative impacts and long-term effects on the food web, as well as on combined effects with other human activities, such as the fisheries. These aspects remain key open issues for a sustainable marine spatial planning

Preface: the WinMon.BE 2013 conference: steps towards an efficient and effective offshore wind farm environmental impact assessment

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Offshore wind park monitoring programmes, lessons learned and recommendations for the future

Over a decade of monitoring offshore wind park environmental impact triggered a reflection on the overall objectives and how to best continue with the monitoring programmes. Essentially, basic monitoring has to be rationalised at the level of the likelihood of impact detection, the meaningfulness of impact size and representativeness of the findings. Targeted monitoring is crucial and should continue to be applied to disentangle processes behind observed impacts, for instance the overarching artificial reef effect caused by wind parks. The major challenge, however, remains to achieve a reliable assessment of the cumulative impacts. A continuous international consultation and collaboration with marine scientists, managers, government officials and industry will be needed to ensure an optimisation of the future monitoring programmes

Modelling impacts of offshore wind farms on trophic web: the Courseulles-sur-Mer case study

International audienceThe French government is planning the construction of three offshore wind farms in Normandy. These offshorewind farms will integrate into an ecosystem already subject to a growing number of anthropogenic disturbancessuch as transportation, fishing, sediment deposit, and sediment extraction. The possible effects of this cumulativestressors on ecosystem functioning are still unknown, but they could impact their resilience, making themsusceptible to changes from one stable state to another.Understanding the behaviour of these marine coastal complex systems is essential in order to anticipate potentialstate changes, and to implement conservation actions in a sustainable manner. Currently, there are noglobal and integrated studies on the effects of construction and exploitation of offshore wind farms. Moreover,approaches are generally focused on the conservation of some species or groups of species. Here, we developa holistic and integrated view of ecosystem impacts through the use of trophic webs modelling tools. Trophicmodels describe the interaction between biological compartments at different trophic levels and are based on thequantification of flow of energy and matter in ecosystems. They allow the application of numerical methods forthe characterization of emergent properties of the ecosystem, also called Ecological Network Analysis (ENA).These indices have been proposed as ecosystem health indicators as they have been demonstrated to be sensitiveto different impacts on marine ecosystems. We present here in detail the strategy for analysing the potentialenvironmental impacts of the construction of the Courseulles-sur-Mer offshore wind farm (Bay of Seine) such asthe reef effect through the use of the Ecopath with Ecosim software. Similar Ecopath simulations will be made inthe future on the Le Tréport offshore wind farm site.Results will contribute to a better knowledge of the impacts of the offshore wind farms on ecosystems.They also allow to define recommendations for environmental managers and industry in terms of monitoring theeffects of Marine Renewable Energy, not only locally, but also on other sites, national and European levels. Finally,this approach could contribute to a better social acceptability of Marine Renewable Energy projects allowing aholistic vision of all pressures on ecosystem

Benthic and fish aggregation inside an offshore wind farm: Which effects on the trophic web functioning?

International audienceThe French government is planning the construction of three offshore wind farms in Normandy. These offshore wind farms will integrate into an ecosystem already subject to a growing number of anthropogenic disturbances such as transportation, fishing, sediment deposit, and sediment extraction. The possible effects of this cumulative stressors on ecosystem functioning are still unknown, but they could impact their resilience, making them susceptible to changes from one stable state to another. Understanding the behaviour of these marine coastal complex systems is essential in order to anticipate potential state changes, and to implement conservation actions in a sustainable manner. Currently, there are no global and integrated studies on the effects of construction and exploitation of offshore wind farms. Moreover, approaches are generally focused on the conservation of some species or groups of species. Here, we develop a holistic and integrated view of ecosystem impacts through the use of trophic webs modelling tools. Trophic models describe the interaction between biological compartments at different trophic levels and are based on the quantification of flow of energy and matter in ecosystems. They allow the application of numerical methods for the characterization of emergent properties of the ecosystem, also called Ecological Network Analysis (ENA). These indices have been proposed as ecosystem health indicators as they have been demonstrated to be sensitive to different impacts on marine ecosystems. We present here in detail the strategy for analysing the potential environmental impacts of the construction of the Courseulles-sur-Mer offshore wind farm (Bay of Seine) such as the reef effect through the use of the Ecopath with Ecosim software. Results will contribute to a better knowledge of the impacts of the offshore wind farms on ecosystems. They also allow to define recommendations for environmental managers and industry in terms of monitoring the effects of Marine Renewable Energy, not only locally, but also on other sites, national and European levels. Finally, this approach could contribute to a better social acceptability of Marine Renewable Energy projects allowing a holistic vision of all pressures on ecosystem

Modelling impacts of offshore wind farms on trophic web: the Courseulles-sur-Mer case study

International audienceThe French government is planning the construction of three offshore wind farms in Normandy. These offshorewind farms will integrate into an ecosystem already subject to a growing number of anthropogenic disturbancessuch as transportation, fishing, sediment deposit, and sediment extraction. The possible effects of this cumulativestressors on ecosystem functioning are still unknown, but they could impact their resilience, making themsusceptible to changes from one stable state to another.Understanding the behaviour of these marine coastal complex systems is essential in order to anticipate potentialstate changes, and to implement conservation actions in a sustainable manner. Currently, there are noglobal and integrated studies on the effects of construction and exploitation of offshore wind farms. Moreover,approaches are generally focused on the conservation of some species or groups of species. Here, we developa holistic and integrated view of ecosystem impacts through the use of trophic webs modelling tools. Trophicmodels describe the interaction between biological compartments at different trophic levels and are based on thequantification of flow of energy and matter in ecosystems. They allow the application of numerical methods forthe characterization of emergent properties of the ecosystem, also called Ecological Network Analysis (ENA).These indices have been proposed as ecosystem health indicators as they have been demonstrated to be sensitiveto different impacts on marine ecosystems. We present here in detail the strategy for analysing the potentialenvironmental impacts of the construction of the Courseulles-sur-Mer offshore wind farm (Bay of Seine) such asthe reef effect through the use of the Ecopath with Ecosim software. Similar Ecopath simulations will be made inthe future on the Le Tréport offshore wind farm site.Results will contribute to a better knowledge of the impacts of the offshore wind farms on ecosystems.They also allow to define recommendations for environmental managers and industry in terms of monitoring theeffects of Marine Renewable Energy, not only locally, but also on other sites, national and European levels. Finally,this approach could contribute to a better social acceptability of Marine Renewable Energy projects allowing aholistic vision of all pressures on ecosystem

Benthic and fish aggregation inside an offshore wind farm: Which effects on the trophic web functioning?

International audienceThe French government is planning the construction of three offshore wind farms in Normandy. These offshore wind farms will integrate into an ecosystem already subject to a growing number of anthropogenic disturbances such as transportation, fishing, sediment deposit, and sediment extraction. The possible effects of this cumulative stressors on ecosystem functioning are still unknown, but they could impact their resilience, making them susceptible to changes from one stable state to another. Understanding the behaviour of these marine coastal complex systems is essential in order to anticipate potential state changes, and to implement conservation actions in a sustainable manner. Currently, there are no global and integrated studies on the effects of construction and exploitation of offshore wind farms. Moreover, approaches are generally focused on the conservation of some species or groups of species. Here, we develop a holistic and integrated view of ecosystem impacts through the use of trophic webs modelling tools. Trophic models describe the interaction between biological compartments at different trophic levels and are based on the quantification of flow of energy and matter in ecosystems. They allow the application of numerical methods for the characterization of emergent properties of the ecosystem, also called Ecological Network Analysis (ENA). These indices have been proposed as ecosystem health indicators as they have been demonstrated to be sensitive to different impacts on marine ecosystems. We present here in detail the strategy for analysing the potential environmental impacts of the construction of the Courseulles-sur-Mer offshore wind farm (Bay of Seine) such as the reef effect through the use of the Ecopath with Ecosim software. Results will contribute to a better knowledge of the impacts of the offshore wind farms on ecosystems. They also allow to define recommendations for environmental managers and industry in terms of monitoring the effects of Marine Renewable Energy, not only locally, but also on other sites, national and European levels. Finally, this approach could contribute to a better social acceptability of Marine Renewable Energy projects allowing a holistic vision of all pressures on ecosystem

Benthic and fish aggregation inside an offshore wind farm: Which effects on the trophic web functioning?

International audienceAs part of the energy transition, the French government is planning the construction of three offshore wind farms in Normandy (Bay of Seine and eastern part of the English Channel, northwestern France) in the next years. These offshore wind farms will be integrated into an ecosystem already facing multiple anthropogenic disturbances such as maritime transport, fisheries, oyster and mussel farming, and sediment dredging. Currently no integrated, ecosystem-based study on the effects of the construction and exploitation of offshore wind farms exists, where biological approaches generally focused on the conservation of some valuable species or groups of species. Complementary trophic web modelling tools were applied to the Bay of Seine ecosystem (to the 50 km 2 area covered by the wind farm) to analyse the potential impacts of benthos and fish aggregation caused by the introduction of additional hard substrates from the piles and the turbine scour protections. An Ecopath ecosystem model composed of 37 compartments, from phytoplankton to seabirds, was built to describe the situation " before " the construction of the wind farm. Then, an Ecosim projection over 30 years was performed after increasing the biomass of targeted benthic and fish compartments. Ecological Network Analysis (ENA) indices were calculated for the two periods, " before " and " after " , to compare network functioning and the overall structural properties of the food web. Our main results showed (1) that the total ecosystem activity, the overall system omnivory (proportion of generalist feeders), and the recycling increased after the construction of the wind farm; (2) that higher trophic levels such as piscivorous fish species, marine mammals, and seabirds responded positively to the aggregation of biomass on piles and turbine scour protections; and (3) a change in key-stone groups after the construction towards more structuring and dominant compartments. Nonetheless, these changes could be considered as limited impacts of the wind farm installation on this coastal trophic web structure and functioning