Acoustical Behavior of the Freshwater Goby Odontobutis obscura

Abstract

The calls of the fresh water goby Odontobutis obscura consisted of a train of about eight pulse sounds, with each lasting for about 9 msec and followed by a silent period of 30–40 msec. Each pulse sound was made of a frequency component of less than 1 kHz. They emitted vigorous calls during the reproductive season, May to July, while the calls were seldom heard in other seasons. No remarkable diurnal variation in the frequency of sound emitting was observed. The calls which are mainly used for threatening invaders, are made by the rubbing of the upper and lower pharyngeal teeth, and amplified by the swim-bladder. The power and the frequency range of a call are limited by the size of swim-bladder, namely the fish size. © 1984, The Japanese Society of Fisheries Science. All rights reserved.