Fundamental Study on the Recapturing Method for the Conditioned Fish School

从1986年开始，在18 × 8 × 1.3m的水池中，对声、视复合刺激法复捕条件鱼条石鲷（Oplegnathus fasciatus）和真鲷（Pagrus major）的可能性进行了为期三年的基础性研究。采用间歇性声音（以2秒间隔发射5秒的500 Hz声音）作为声刺激。可视屏幕是直径为1米的圆柱形，由八根钢筋和具有黑色和白色的彩色条纹的1米高的中心杆组成。将筛网悬挂在漂浮装置（3* 3 m）上，并通过电机以4 rpm的速度旋转。通过多次投饵试验，研究了鱼对视觉和听觉刺激的条件反射过程。在鱼类条件反射完成后，进行了几个实验，详细讨论了条件反射的消退与环境变化和非强化期持续时间的关系。在饲养试验的强化下，条件反射在4-5天内就已出现。在多次中断的再训练后，鹦鹉鲈鱼的条件反射保持能力上级。根据对鱼在水槽中行为的比较观察，认为漂浮装置和马达噪声影响了条件反射的声刺激和视觉刺激的性质。将鱼运输到不同的鱼缸后，真鲷表现出几乎相同的行为，而鲈鱼没有表现出类似的行为，从这些结果来看，使用复合刺激将更有效地夺回条件学校。

The fundamental study was conducted on the possibility of recapturing the conditioned fish of parrot bass Oplegnathus fasciatus and red sea bream Pagrus major by the acoustic and visual complex stimuli, in a tank (18*8*1.3m) for three years since 1986. The intermittent sound (500Hz sound of 5 seconds transmitting at 2 seconds interval) was employed as the acoustic stimulus. A visual screen was a cylinder type of 1 meter in diameter, consisted of eight steel bars and an center pole of 1 meter height having the colored stripe of black and white. The screen was suspended from the floating device (3*3m) and rotated by the motor at the speed of 4rpm. The process of the conditioned reflex of fish to the acoustic and visual stimuli were examined with the numbers of feeding trial. After the completion of the conditioned reflex of fish, several experiments were carried out for the detailed discussion on the extinction of the conditioned reflex in relation to the environmental change and the duration of the un-reinforcement period. With the reinforcement by the feeding trials, the conditioned reflex was require in 4-5 days. Parrot bass showed the superior ability in the retention of the conditioned reflex after several breaks of the re-training. According to the comparative observation of the fish behaviour in the tank, the floating device and the motor noise were considered to affect the nature of the acoustic and visual stimuli for the conditioned reflex. After the transportation of fish to the different tanks, red sea bream showed almost the similar behaviour, while parrot bass not showed it. Judging from these results, it will be more effective for recapturing the conditioned school that the complex stimuli are used.