Snapping Shrimp Sound Measured Under Laboratory Conditions

Abstract

The typical temporal waveforms and spectra of the sounds produced by the three species of snapping shrimp with different claw shapes and almost the same claw lengths were investigated under laboratory conditions. The sound spectra generated by one species of snapping shrimp were also investigated for various claw lengths. For the three species of snapping shrimp, their typical temporal waveforms were similar, but their sound spectra and pulse durations differed. This difference was related to the size of the single cavitation bubble, which was generated by the high-speed water jet emitted from the snapping shrimp claw. The range of difference in the times between the snapping shrimp claw closure and the collapse of the single cavitation bubble for the three species of snapping shrimp seemed to be determined by the difference in the claw shape. The collapse time, the equilibrium radius, and the maximal radius of the cavitation bubble for each species were estimated from the first peak frequency component in the snapping shrimp sound spectrum. For one species of snapping shrimp, the peak frequency components in the sound spectra were observed for various claw lengths and their superposition could be considered as the cause that the broad peak frequency components were variously observed in the averaged snapping shrimp sound spectra, which were measured in many shallow water areas.