“…Anthropogenic underwater sound generated by ships, power generation, oil and gas production, fishing, aquaculture and other industries is a growing concern as it may have negative impacts on fish and other marine organisms (Popper and Hastings, 2009; Boyed et al , 2011; Normandeau Associates Inc., 2012; Hawkins et al , 2015). Airguns used for offshore ocean seismic exploration by the oil and gas industry generate acute, repetitive, intense sounds (Hawkins et al , 2014; Popper et al , 2014). The airgun’s omnidirectional sound impulse has its greatest energy at low frequencies (20–50 Hz; Nieukirk et al , 2004; Laws and Hedgeland, 2008).…”