Many marine organisms produce sound during key life history events. Identifying and tracking these sounds can reveal spatial and temporal patterns of species occurrence and behaviors. We describe the temporal patterns of striped cusk eel Ophidion marginatum calls across approximately 1 yr in Nantucket Sound, MA, USA, the location of a proposed offshore wind energy installation. Stereotyped calls typical of courtship and spawning were detected from April to October with clear diel, monthly, and seasonal patterns. Acoustic energy increased in the evenings and peaked during crepuscular periods, with the dusk call levels typically higher in energy and more rapid in onset than those from near-dawn periods. Increased call energy and substantial overlap of calls during certain periods suggest that many cusk eels were often calling simultaneously. Call energy (measured in energy flux density) peaked in July and patterns followed seasonal changes in sunrise and sunset. Sound levels were high (over 150 dB re 1 µPa 2 s) during the summer, indicating that this cusk eel population is a substantial contributor to the local soundscape. The stereotyped cusk eel signals and clear temporal energy patterns potentially provide a bioacoustic signal that can be used to monitor changes to the local environment and its soundscape.

Understanding the cues that drive larval fish settlement is critical for managing reef systems under stress. Reef sound is increasingly reported to influence fish recruitment, yet the physical and acoustic environment in which larval fish settle varies in space and time. Accordingly, testing potential settlement cues under different conditions is vital for understanding their ecological importance. We conducted 2 sets of field playback experiments in St. John, US Virgin Islands, one nearshore (10 m depth) and the second ‘offshore’ (25 m depth), to assess the effects of reef soundscape playback on settlement rates of multiple reef fish families. In each experiment, nightly currents were quantified and we replicated the diel soundscape cycle using high, low, and control (silent) amplitude recordings from nearby reefs. The first experiment revealed significant current-based, down-stream reduction in larval fish catches in subsurface light traps and a significant effect of increasing amplitude of reef playbacks on larval lizardfish (Synodontidae) catches. In the second, offshore experiment which had no current effect, increasing reef playback amplitude led to a significantly greater catch of parrotfish (Scaridae) larvae and decreased larval pelagic fish catch. Total reef fish larvae only showed attraction to reef playbacks at the most nearshore site. This work demonstrates that while sound can play a role in the settlement of certain reef fishes, responses are influenced by multiple factors, including larger-scale physical processes, underscoring the need to consider the scale of soundscape cues for reef fish settlement within an oceanographic context.