Advances in research on the effects of offshore wind farm on fish welfare

Wind power, as one of the important clean energy sources, has been highly valued by all countries in the world to reduce carbon emissions in the power industry and achieve the goal of carbon neutralization. With the continuous development and utilization of onshore wind power, space resources of onshore wind farms are becoming increasingly scarce. Human beings are beginning to bring the wind power industry into the broader ocean. The coastline of China is long and close to the power load area. In recent years, offshore wind farm construction has achieved rapid development. Offshore wind power will become one of the main directions of renewable energy development in China in the future. During the construction and operation of offshore wind power projects, noise and electromagnetic pollution may occur, which may have a certain negative impact on marine life. Research and evaluation of wind farms is the prerequisite to ensuring the sustainable development of wind farms. In this paper, the literature on the Influence Factors of fishes in offshore wind farms is sorted out and analyzed. It is summarized as follows: at present, there are fewer types of research on acoustic effects of offshore wind farms at home and abroad in field investigation, construction period, operation period, and outage period, and fewer studies on marine invertebrates, marine mammals, and benthos. Piling is the main construction stage, which produces high-intensity short-term impact noise to fish. Fish will startle and swim within a certain range, produce stress response, increase breathing frequency, and reduce the ability of bio-acoustic detection, thus increasing the risk of predation, but it has no significant impact on the natural mortality rate. Noise generated during the operation of offshore wind farms can disguise fish communication and direction signals and lead to stress response, but will not cause physiological damage or sustained avoidance response. As far as the influence of electromagnetic fields generated by offshore wind farms is concerned, excessive magnetic field intensity will delay the development of fish embryos, significantly affect their biochemical indicators, and even kill them. Some fishes, such as eels, are positioned by magnetic fields, which reduce the speed of fish swimming in offshore wind farms but do not significantly affect the overall migration behavior. Pile foundations of fixed offshore turbines have similar aggregation effects on fish as artificial reefs, so they will increase fish habitats and thus have a positive impact on species diversity. Long-term effects of noise and electromagnetic fields on fish health during offshore wind farm operations have not been determined. We suggest that in the future, we need to study the effects of sector noise on different species, different life cycle stages, and different perceptions of the sound structure of fish, as well as on the physiology and genetics of fish. Systematic research, combined with laboratory and field experiments, has proved the mechanism of its effects on fish and established relevant research standards and preventive measures.