Vocal behavior of the endangered splendid toadfish and potential masking by anthropogenic noise

Abstract

Abstract Vessel‐related noise is a potential stressor for coral reef fauna. The Parque Nacional Arrecifes de Cozumel (PNAC) is a Mexican Marine Protected Area that is exposed to pervasive vessel traffic. PNAC is also the primary range of splendid toadfish (Sanopus splendidus, family Batrachoididae), an IUCN red‐listed soniferous fish for which vessel noise may represent a threat. We conducted a passive acoustic monitoring survey during summer of 2017 at Paraiso Reef in PNAC and obtained the first scientific recordings from splendid toadfish, enabling a vocal characterization of the species. We simultaneously collected data on sound levels of vessels passing near the reef. High noise levels of cruise ship and small motorboat traffic caused elevated anthropogenic sound pressure levels for up to 15 hr per day in the same bandwidth as toadfish vocalizations. A single cruise ship added up to 4 dB above nighttime ambient levels while small motorboat traffic added up to 7 dB. The overlap of toadfish vocalizations and vessel‐related noise highlights the susceptibility of splendid toadfish to acoustic masking and reduction in communication space throughout the day, warranting further study. Because acoustic communication is critical to toadfish reproductive success, noise from cruise ships and small motorboats may threaten splendid toadfish individuals or population viability.

Keywords

• acoustic masking
• coral reef
• passive acoustic monitoring
• soundscape
• toadfish