In situ approach to characterize effects of pile-driving on black sea bass behavior, Centroprisits striata

Abstract

With the threat of climate change and global energy demands rapidly growing, offshore wind farms are quickly becoming a contender in renewable energy strategies in countries around the world, including the United States. In the US, numerous offshore wind turbines are in the planning process for coastal Mid-Atlantic waters, spurring investigation into potential effects of the high-intensity construction noise on local species. Black sea bass, Centropristis striata, is a commercially important mid-water fish that inhabits these same waters and are reported to experience behavioral changes in response to pile-driving, although only demonstrated in the lab. Verification and expansion on these results requires an in situ approach to minimize tank effects on sound propagation and animal behavior. This study, conducted in coastal waters of Woods Hole, MA, used video observation to characterize behavior of 40 caged black sea bass before and during 15-min bouts of actual impact and vibratory hammer pile driving, repeated 5 times per day. Pressure and particle motion were measured. We examined immediate reactions to the onset of noise, prolonged behavioral changes, and habituation. Initial results show increased hiding or sheltering behaviors, as well as bursts of escape-motivated movements in response to the noise. While preliminary, the results suggest that pile driving can induce a range of behavioral impacts on this important fisheries species, and some concern is warranted with respect to offshore wind development.