Acoustic behaviours of large crustaceans in NE Atlantic coastal habitats

Although many studies have investigated the benthic environment of temperate marine waters, little is known about the acoustic behaviour of the organisms in these habitats, particularly crustaceans. This study focused on the acoustic behaviour of large crustaceans in NE Atlantic coastal regions. A total of 11 crustacean species were recorded in tank-based experiments to identify sound-producing species and the behaviours associated with their sounds as well as to quantitatively characterise and compare the sounds. A total of 34 sounds were associated with behaviours such as moving, feeding, mandible rubbing, swimming, species-specific behaviour and other unidentified behaviours. The sounds included single pulse and pulse train signals that were distributed across a peak frequency spectrum of 3 to 45 kHz with received levels between 93 and 142 dB re 1 mu Pa (peak to peak). The results demonstrated that Brachyura had the most diverse sound types. Using a combination of several acoustic features, 24% of the recorded sounds appeared to have a high potential to be differentiated in field recordings: the feeding sound of Cancer pagurus, Carcinus maenas, Necora puber and Pachygrapsus marmoratus; the species-specific sound of C. pagurus and Galathea squamifera; and the pulse train sound associated with unidentified behaviours of Lophozozymus incisus and N. puber. These findings extend the existing crustacean acoustic library in marine ecosystems and contribute to our understanding of in situ acoustic recordings in temperate regions.