Research On The Technology Of Sea Ranching-based Acoustic Taming Of Black Sea Bream (Sparus Macrocephalus)

Under the background that the sea ranching construction is postpone in a national widescale, it is a matter of importance to have effective control and management of those targetorganisms in sea ranching. One of the control management, acoustic taming, has effectivecontrolling function for the behavior of fishes in sea ranching. Start from the in site acoustictaming experiment and the related theory of the acoustic taming experiment. The in siteexperiment has two parts: The experiments are composed of tank and cage acoustic taming.As scientific evidence, the work of theoretical part is designing sound supervising system.Tagging experiments on domesticated Sparus macrocephalus and recapture with playingsound, draw conclusion from the experiments then design acoustic taming and recapturedevice profitable to sea ranching. From those researches we can draw the followingconclusion.(1) Tank-based acoustic taming experiment is using sine wave of300Hz and400Hzalternate sound combines with feeding. The results shows that the alternate sound to therevulsive effect of Sparus macrocephalus experience3time node, which are adaptationperiod、variation period and stabilization period; the response time of taming period from1thto4thdays are extremely significant higher than holding period(P<0.01), and there is nosignificant difference(P>0.05) on the aggregation ratios, we consider Sparusmacrocephalus is negative trend to sound; it appears positive feedback to sound stimulationsince the5thand6thdays, and the aggregation rates rise quickly; the activity of fish tended tobe stabilized from7thto10thdays, there is no significant difference(P>0.05) on the responsetime between taming period and holding period, and the10thday of taming period appearsthe minimum response time of the entire trial period. moreover, there is a great difference(P<0.01) of taming period on the aggregation ratios than holding period from the6thday,and the aggregation ratio reaches100%entirely from8thto10thdays; the intersection ofaverage aggregation ratio of Sparus macrocephalus is found, however, there is nosignificant difference (P>0.05) between before feeding and after satiation, in addition, wenotice that the more fishes hungry, the more exciting. We conclude that sine wave of300Hz and400Hz alternate sound has a distinct inductive effect on Sparus macrocephalus,acoustic taming can be used as a supplementary method for gathering fishes, but require acombination of feeding to make a greater effect.(2) Inhabits waters’ background sound of Sparus macrocephalus in utilized to theacoustic taming in a cage. The results base on the analysis of result and participantexperiment observation show excellent aggregation effect. Acoustic taming on juvenileSparus macrocephalus needs three stages:1) acclimatization;2) impulsion of demanding food (outside sign is the fish reaches certain length and weight);3) build condition reflexbetween sound and bait. Sparus macrocephalus can identify different sounds and maintainlongtime memory.(3) When playing sound, and Sparus macrocephalus were gathered, then lighting thered, yellow, blue, green led light separately, results show that no matter what kind of thelight color is used, the intensity of the light is decreased with the distance. In a fixeddistance, the intensity of the red light is the strongest, followed by yellow light and blue,while the intensity of blue light is the weakest. Sparus macrocephalus prefer to live in thedim light environment, so it is better to use light intensity less than1000lx when doing theexperiment. Too strong light intensity is not favorable to the effective gathering of the fishwhen doing acoustic taming.(4) Inhabits waters’ background sound without feeding can make Nibea albifloranearby sound source and doing winding exercise in group. Nibea albiflora in cage areaggregated by sound wave. Young fishes of Barracuda stay nearby the sound source whenplaying sound are in the need of forage but not sound attraction.(5) Put those marked Sparus macrocephalus in the discharge point and playing soundunderwater for5min, no Sparus macrocephalus swim to the observation area. The food isthrough into the water, but Sparus macrocephalus don’t swim up to the water surface to getfood, keeping put food and give sound for20min, Sparus macrocephalus still do not cometo the surface part of water.(6) Sound supervising system is designed according to the special requirement in theoceanic pasture opening environment. Hydrophone layout and data collection under thecondition of the variable nature fish sound pressure is particularly discussed. Over strengthsignal area and over distance signal area are defined which provide scientific reference todesign a reasonable sound supervising system. By adopting RHS-15hydrophone, the validsmall signal supervising method of variable fish sound pressure amplitude and frequency isobtained.(7) The design of acoustic taming and recapture system consists of two parts: acoustictaming device and recapture device. According to the fishes’ phonotaxis and phototaxis inthe sea ranching, and specific environment in the sea ranching. Combining sound, light,food and other key information of acoustic taming，the experiment aim to realize theautomatic device. And use modern techno lodge to realize remote location and control ofacoustic taming, recapture when it is necessary.