Short-term changes in the underwater soundscape of Mosquito Lagoon after Hurricane Ian

Abstract

During late September 2022, Hurricane Ian passed over the east coast of Florida and Mosquito Lagoon. This 4740-acre body of water is part of a larger estuary system sandwiched between the mainland and narrow barrier islands. Two-thirds of the lagoon is located within Canaveral National Seashore, which helps maintain a balance between protecting its rich biodiversity and allowing access for recreational boating. As part of a previously planned study, we deployed two HydroMoths in Mosquito Lagoon to capture the underwater soundscape for two months from September 24 to November 19. Our sampling protocol recorded 5 min of continuous sound at the top and bottom of every hour, with the idea that we could begin to explore diurnal and lunar cycles. When Hurricane Ian's path took it directly over our recorders, we were given an unplanned opportunity to document how the underwater soundscape would respond. The most striking change came from the oyster toadfish (Opsanus tau). Calls from males of this species are a prominent part of the underwater soundscape in Mosquito Lagoon during their breeding season. In the days immediately following Hurricane Ian, they lowered the fundamental frequency of their calls leading to an audible change in pitch.