광에 대한 어류의 행동을 조사하기 위하여 까치복 Fugu xanthopterus에 광의 세기가 서로 다른 8가지 백색인공광원으로 광자극을 주어, 그에 대한 반응을 주간과 야간으로 구분 조사한 결과는 다음과 같다. 1. 광자극에 대한 수조내의 구간별분포는 광원쪽구간에 많이 모여 분포곡선은 대체로 L자형이 되었으나, 광의 세기에 따라 그 형태가 다소 차이가 있었으며 주야간의 차이는 뚜렷하지 않았다. 2. 수중조도가 높아짐에 따라 광원쪽에서 더 많이 모이는 경향을 나타냈으며 주간보다 야간에 다소 많이 모였다. 3. 집어율이 최대가 되는 수중조도(적정조도)는 298.56 lux(188.44~444.96 lux)로써 주야간에 같았으며, 최대집어율은 주간에 47.30%, 야간에 50.43%로써 야간에 더 높았다. 4. 조명시간이 경과함에 따라 집어율은 증가하거나 증가한 후 감소하는 경향을 보였으나, 계속 불안정하게 변동했으며 주야간의 차이는 뚜렷하지 않았다.

The purpose of this study is to find the light intensity which induced maximum gathering rate and to observe the variation of the gathering rate both in daytime and tat night by using Striped puffer, Fugu xanthopterus (Temminck et Schlegel). An experimental tank(360L×50W×55H cm) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Eight artificial light sources were prepared by combination of three light bulbs (10W, 60W, 100W) and eight filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 60 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 298.56 lux (188.44-444.96 lux) at daytime and 298.56 lux (188.44-444.96 lux) at night. The variation of the gathering rate of fish in illumination time was increasing trend fluctuately and did not show any distinctive difference between day and night.

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