罗非鱼声控投饵方法

鱼类的摄食活力可以用摄食过程发出的声音直接测量。本研究通过构建声学监测平台,应用带宽1 Hz-470 kHz,在40 kHz以下自由场电压灵敏度级-217 dB(基准值为1 V/μPa)的水声检测设备,采集罗非鱼摄食过程中产生的声信号,分析其摄食活力。研究表明,罗非鱼摄食时发出的声音在0-6 kHz可区分于背景噪声,其声功率与摄食活力呈正相关。声功率移动平均值反应鱼摄食活力趋势,可作为食欲反馈,结合生长模型和投喂模型可以组成投饵策略。

Acoustic control of feeding in Tilapia culture

The technique of measuring fish appetite is the key to accurate automatic feeding. As light attenuates quickly in the water, visual observation is not an effective method to measure the fish appetite in the turbid water body of fish farms. Recent studies have shown that the feeding activity of fish can be measured directly by monitoring sounds emitted by the fish during a feeding period. In our study, we used an acoustic monitoring platform that was composed of a programmable filter and a standard measuring hydrophone, with bandwidth from 1 Hz to 470 kHz and with free field voltage sensitivity of -217 dB （reference level 1 V/μPa） under 40 kHz. Tilapias in the laboratory pond were fed by hand, while the feeding sound of Tilapia was recorded for the analysis of its feeding activity. The feeding sound with the frequency ranging from 0 to 6 kHz could be distinguished from background noises. The appetite of Tilapias faded after a period of feeding, resulting in the decrease in feeding activity and the subsequent change in the acoustic power. The acoustic power had a significant positive correlation with the feeding activity. Therefore efficient feeding strategies can be established, based on the appetite feedback （ generated by the moving average of acoustic power） together with growth models and feeding models.