고등어 旋綱의 魚探記錄에 關하여 : Submarine Illumination and Distribution of Fish Shoal Aggregated by Attracting Lamp 集魚??誘集時 水中照度와 魚群分布 = On the Fish Finder Recordings of Mackerel Purse seine

다국어 초록 (Multilingual Abstract)

This study described on the submarine illumination and the fish finder recordings for the distribution of fish shoal when the mackerel of fishes of the main object in the purse seine of the Jeju was aggregated by attracting lamp, which was investigated from Apr, to Oct, 1975 in the mackerel fishing ground of Jeju near sea.
Arrangement of the attracting lamps and a method of submarine illumination's measurement indicated to Fig. 2.
1. Results of a submarine illumination's measurement was equal to Fig. 4A, B
2. In case of fish shoal was aggregated by submarine attracting lamp, distribution of a vertical direction was 10∼25m depth centering lamp and distribution of a horizontal direction was 20∼30m radius.
Submarine illumination of this time was 12-1 Lux at vertical direction and 1∼0.2 Lux at horizonted direction.
3. Distance of between the fish shoal and the lamp reduced about 4∼5m in the 30m boundary centering attracting lamp.
4. Alternation of age of the moon for a unit attracting catches show a peak in 6 day and 27 day of age of the moon.
5. Alternation of attracting time was 70% before 2.00 a.m and 28% after 2.00 a.m into 2.00 hour boundary.
6. Catches for the time required of aggregating was 44.2% in 1∼1.5 hour's time and 45.5% in 1.5∼2hour's time.