Validación de hidrófonos de bajo costo para la detección acústica de los delfines nariz de botella (Tursiops truncatus truncatus) en un ambiente controlado

In recent years, passive acoustics has emerged as an effective tool for detecting cetaceans, particularly in difficult-to-observe species. In addition to being a non-invasive technique, it allows for animal monitoring without disturbing them, regardless of visibility conditions. However, the high cost of the equipment associated with this technique presents a significant challenge for developing countries. The objective of this project was to compare acoustic signals of the bottlenose dolphin (Tursiops truncatus truncatus) recorded using a commercial self-contained hydrophone and a low-cost, handcrafted alternative. Recordings were conducted at the Aquarium Mar del Plata, Argentina, using both hydrophones simultaneously over a 50-min period. Recorded signals were characterized and tonal signals (whistles) detected by each device were counted. Robust parameters for each whistle were obtained using the Raven Pro software. Based on the analysis of coincident whistles, it was determined that the measured parameters did not show significant differences between the two instruments, demonstrating the effectiveness of low-cost hydrophones for acoustically monitoring bottlenose dolphins in controlled environments, with the potential for use in other settings such as open water.