A STUDY ON THE INTERCEPTING MECHANISM of AN AIR-BUBBLE CURTAIN ON BLACK PORGY (SPARUS MACROCEPHALUS)
- 海洋环境－已发表论文 
于1987年3月—1988年1月在室内水池中观测黑鲷失去视觉后对气泡幕的反应，比较同种参数气泡幕对正常视觉黑鲷与失去视觉黑鲷的阻拦效果；采用大小适宜的红黑双层布将鱼的双眼裹住，使鱼失去视觉，探讨气泡幕对鱼类作用的机制。结果表明，黑鲷失去视觉后，活动受到很大限制，游泳行为发生变化，游速显著低于正常视觉时，气泡幕对其阻拦率由正常视觉时75.1%下降到45.2%，下降了39.8%。T-检验表明，两种视觉状态下的阻拦率存在极显著差异（P＜0.01）。黑鲷失去视觉后，并未对气泡幕产生显著的适应。实验表明，气泡幕除了对鱼类视觉产生作用外，还对听觉及其它感觉产生作用。Indoor experiments were Undrtakn to investigate into the intercepting effects of animmovable air-bubble curtain (IBC) on artificially blinded black porgy (Sparus macrocephalus)during March 1987 to January 1988.The IBC was constructed from a hard polyethylene pipe (17.5mm i.d.),fixed on the middle part of the bottom of an experimental tank, from which colunms ofbobbles escaped through a series of holes (0.5 mm i.d.) bored in the upper side of the pipe at5.0cm intervals.Compressed air with a pressare of 0.25kg / cm2 was suppied by a compressor(Modl: A1301, Japan.The experimental tank (3.5m long, 2.5m wide, and 0.8m deep), filled withseawater with more than 3.5m diaphanity, was surroundd with bleck cloth.The tank top wasilluminated with two 40W fluorescent lamps giving 80 1x on the central surface to fasilitatemonitoring fish behaviors.The experimental fisly with a 8.0-13.5 cm body-length, were obtainedfrom a local fish hatohery in Xiamen and maintrined in the laboratory for 1-2 days prior to testTwenty-five fish in good conditions were randomly selected and divided into five groups to be tested.The five fish with their eyes being blinded with a foded red-black cloth were put in theexperimental tank and allowed to acclimare the new envirorunnt for 24-48h prior to test.Eachexperiment was carried out by dividing into two testing sections, for an aeration experiment and acontrol experiment (without IBC).The obeervation period of each section was 1h.The controlexperiment was peiformed randomly before or after the aeration experiment Three replicatos weresuccessively carried out for eash of the fish groups.In all experiments, the behaviors of fish wereobeerved with a CC-1 500 television camera mounted over the tank, and the events were recothedon a video-tape.The time when the fish passed through the air-bubble curtain or the air pipe andthe number of passage were registered readily.The results show that when fish lose their visions,their achvities are restricted and they swim slower than those in a normal vision state.The IBC isstill an obstacle to the blinded fish.The obstructing rate of IBC to fish decrease from 75.1% (normal)to 45.2% (blinded).There is a significan difference in the obetructing rate (t-test P < 0.01)between the two vision states.In addition, the black porgy has no marked adapation to IBC whenthey lose their vision.The results suggest tha the air-bubble curtain has effects on the behaviors ofthe blask porgy through its vision, audition and other sensory systems.Perhaps these effects varyunder different conditions and with different fish species.