Vessel noise impacts on sciaenid fishes of the northern Gulf of Mexico coast

Many fish species in the family Sciaenidae produce sounds during reproduction. Variability among sciaenid species in the season of peak spawning, sound frequency spectra, and hearing range and sensitivity may result in species-specific vessel noise impacts, as vessel traffic is more prevalent in the summer and may impart hearing loss differentially among frequencies. We have examined the potential of noise to disrupt communication for sciaenid fishes in the northern Gulf of Mexico with a multidisciplinary approach using passive acoustic monitoring (PAM) and laboratory experiments. PAM observations of fish choruses in association with vessel noise indicate that Red Drum (Sciaenops ocellatus), Spotted Seatrout (Cynoscion nebulosus), and Silver Perch (Bairdiella chrysoura) exhibit modest reduction in chorus intensity, consistent with a prediction of disturbance in the presence of vessel noise. Lab experiments with Atlantic Croaker (Micropogonias undulatus) indicate a reduction in hearing sensitivity following noise exposure. Hair cells of the sensory epithelium of the saccule in Atlantic Croaker ears proliferate with growth, but following noise exposure in the lab, hair cell proliferation rates do not increase. Together, these results indicate that acoustic communication in sciaenid fishes may be impacted by reducing signal-noise, lowering calling activity, and decreasing acoustic sensitivity of listening fish.