The effects of high intensity impulsive sound on young European sea bass Dicentrarchus labrax, with special attention to pile driving
Debusschere, E.; Hostens, K.; Vandendriessche, S.; Botteldooren, D.; Vincx, M.; Degraer, S. (2016). The effects of high intensity impulsive sound on young European sea bass Dicentrarchus labrax, with special attention to pile driving, in: Degraer, S. et al. (Ed.) Environmental impacts of offshore wind farms in the Belgian part of the North Sea: Environmental impact monitoring reloaded. pp. 169-183 In: Degraer, S. et al. (Ed.) (2016). Environmental impacts of offshore wind farms in the Belgian part of the North Sea: Environmental impact monitoring reloaded. Royal Belgian Institute of Natural Sciences, OD Natural Environment, Marine Ecology and Management Section: Brussels. ISBN 978-90-8264-120-2. ix, 287 pp., more | |
Authors | | Top | - Debusschere, E., more
- Hostens, K., more
- Vandendriessche, S., more
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Abstract | Throughout the North Sea, a new anthropogenic sound source, pile driving, was recently introduced. It is the main method to install offshore wind farms (OWFs) and will regularly be used during the next couple of years. Pile driving generates strong impulsive noise that can affect the health and wellbeing of marine life. However, the exact impact, the underlying mechanisms and the ecological consequences of anthropogenic sound on marine life are not yet understood, especially for fish. This study investigated the impact of pile driving on young sea bass Dicentrarchus labrax. More specifically, the acute and delayed mortality, acute and chronic bphysiological stress responses and the impact of lower intensity impulsive sound on the fish behaviour were assessed through field and laboratory experiments. A field experiment at 45 m from the pile driving activity revealed no acute or delayed mortality but the fish showed strong acute secondary stress responses, a 50% decrease in oxygen consumption rate. This result could not be completely reproduced by two laboratory studies, indicating the importance of the frequency content in addition to the standard sound metrics for the physiological stress responses. Furthermore, juvenile fish reduced their swimming activity and ceased all aggressive attacks on conspecifics at the onset of the impulsive sound exposure, but showed behavioural recovery within 25 minutes. The results also showed that the initial response can change under repeated exposure. Based on these acute short term effects, the ecological consequences of pile driving sound on fish health are probably subtle. More research on multiple species and at population level are required as well as long-term data, especially on behavioural responses, in order to decide on the ecological relevance of pile driving on young fish. |
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