Abstract
The author carried out an experiment to find out the response of rock trout, Hexagrammos otakii (Jordan et starks) to the color lights. The experimental tank (360L$\times$50W$\times$55H cm) was set up in a dark room. Six longitudinal sections with 60cm intervals are marked in the tank to observe the loction of the fish. Water depth in the tank was kept 50cm level. Light bulbs of 20W at the both ends of the tank projected the light horizontally into the tank. Two different colored filters were selected from four colors of red, blue, yellow, and white, and they were placed in front of the light bulbs to make different colors of light. Light intensity were controlled by use of auxiliary filters intercepted between the bulb and the filter. The fishes were acclimatized in the dark for 50 minutes before they were 3employed in the experiment. Upon turning on the light, the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was given as the gathering rate of the fish. The colors favourited by the fish was found in the order of white, yellow, red and blue in day time, and red, yellow, blue and white at night time. The gathering rate of fish on illumination period was small and comparatively fluctuated with stability. The difference of the gathering rates on two different colors of light was great.
색광에 대한 쥐노래미 Hexagrammos otakii의 행동을 조사하기 위하여, 2가지씩의 서로 다른 색광을 조합하여 수조의 양단에서 동시에 광자극을 가했을 때의 반응을 주간과 야간으로 구분 조사한 결과는 다음과 같다. 1. 수조내에서의 쥐노래미의 구간별분포곡선은 양단구조에 다소 많이 모여 대체로 U자형이 되었다. 2. 양색광원쪽에서의 평균분포차는 6.00%(0.50~20.80%)였고, 주간(4.68%)보다 야간(7.31%)에 더컸다. 3. 쥐노래미가 잘 모이는 색광은 주간에는 백색, 황색, 적색, 청색의 순이며 야간에는 적색, 황색, 청색, 백색의 순으로 나타났다. 4. 조명시간의 경과에 따른 집어율의 변화는 적었으며 비교적 안정하게 변동했다. 5. 두가지 색광에 대한 집어율의 차는 비교적 뚜렷하였다.