Sound character of the coconut crab (Birgus latro) of Bacan Island

Abstract

Coconut crab (Birgus latro) is a unique land living crustacea, that has economical value in some countries. While the abundance of crab in nature is very rare. The crab is nowadays being a protected organism. The study aims to determine the characteristics of sound produced by the coconut crabs. The data collection was conducted in November-December 2018. The sound was recorded in the new moon, using a microphone, TOA and recorder. Data of the sound was analyzed using software Wavelab, Matlab, and Excel. The sound type obtained by the coconut crab was snap sound that is used for repelling an opponent to came, and stridulating sound used for communicating. Male coconut crab producing stridulating sound to attract the female. The results of this study indicate that the snap sound had high frequency sound with a range of 400-500 Hz, but it was a high intensity sound. While the stridulating sound has a relatively high frequency with a range of 300-400 Hz, but low in its intensity.