Acoustic behaviour is increasingly recognized as a key component of animal interactions, yet it remains poorly explored in freshwater invertebrates. The red swamp crayfish (Procambarus clarkii) is a globally invasive species whose behavioural plasticity, aggressive social dynamics, and high tolerance to pollution and habitat degradation drive its ecological success. While P. clarkii is known to produce sounds, the specific behavioural contexts and ecological relevance of these acoustic signals remain unclear.

The "Sound Cray Project" investigates underwater sound production in P. clarkii across both controlled and natural conditions to link acoustic activity with social behaviour and detectability. To establish an acoustic baseline, crayfish were monitored in the laboratory using AudioMoth loggers (Open Acoustic Devices) across various social and environmental contexts, including pairs and groups, both with and without access to burrows. Recordings were captured at a sampling frequency of 96 kHz for 5 minutes every 30 minutes over a three-day period per experimental group. Following the isolation of sound emissions from the data, primary temporal, spectral, amplitude, and energy parameters were characterized. The results revealed that sound emissions differ significantly depending on the behavioural context.

To validate these findings in the wild, the same AudioMoth loggers were deployed in the natural environments of the Avigliana Lakes Nature Park (Italy). Field recordings were performed continuously at 96 kHz for four days, specifically targeting the hours from dusk to dawn. P. clarkii acoustic emissions were successfully detected in these natural contexts, suggesting that bioacoustics could serve as a promising, innovative tool for monitoring this invasive species.

By bridging laboratory and field bioacoustics, this research evaluates whether sound production can serve as a behavioural indicator to predict ecological patterns. Beyond advancing fundamental knowledge of invertebrate communication, this work explores scalable, non-invasive strategies to improve the management of freshwater biological invasions.