The results of performance of tagging programs of the Korean exploratory fishery for Dissostichus spp. in 88.1 in the 2010/11 season

The Korean flagged bottom longliners, “Jung Woo No. 2” and “Jung Woo No. 3”, have participated in the exploratory fishery from 1st Dec 2010 to 10th Jan 2011 for Dissostichus spp. The fisheries took place in subarea 88.1 BCJL. During their activities, the vessels gathered scientific information on Dissostichus spp. and by-catch such as their distribution, size, sex, weight, etc. This paper presented the results from the fisheries and comparison of statistics in each SSRU.

Total catch including by-catches in 88.1 BCJL were 35,436 fishes. Dissostichus Spp. was the highest catch, contributing 99.62% to the total catches in 78 hauls while by-catches were 133 fish. The CPUEs of Dissostichus Spp. in 88.1 J and L appeared dramatic higher rate than the CPUEs in 88.1 B and C. Mean CPUE (number / km) of Dissostichus Spp. for total of 78 sets, for instance, was 16.67911. This figure was higher than the figure of 5.676294 in 88.1 B and the figure of 2.719449 in 88.1 C. On the other hand, CPUE (number / km) in both 88.1 J and L were over 19. The highest CPUEs in each SSRU were the CPUE at a depth of 1,500 to 1,600M in 88.1B and C, a depth of 600 to 700 in 88.1J and L.

The composition of the by-catch species was WGR, ANT, GRV, PGR, and NOS in subarea 88.1. WGR was the highest catch among the by-catches. WGR, ANT were found in 88.1 BC and GRV was found in 88.1 B only. In 88.1 J, PGR and NOS were caught without any WGR, ANT and GRV.

The ratio of males to females in subarea 88.1 BC was 1:0.63 (males: 363, females: 228 fishes) and it was 1:1.20 (males: 579, females: 696 fishes) in subarea 88.1 JL. The ratio of males to females in 88.1 BC is higher than the ratio in 88.1 JL. Number of males was dominated in all range of depth from 1,400 m to 2,000 m of 88.1 BC. On the other hand, females were predominant in subarea 88.1 JL. Although females were mostly predominant in 88.1 JL, at depth from 600 m to 700m in 88.1L number of males was more than that of females(male 16 : female 14).

Size of sampled fish over 120 cm was highly concentrated in 88.1 BC. On the other hand, size of sampled fish up to 120 cm was densely populated in 88.1 JL. Size of Dissostichus Spp. caught in  88.1 B was most widely distributed compared to 88.1 C, J and L. It ranged from 59 cm to 187 cm. On the other hand, Size of Dissostichus Spp. in 88.1 C was concentrated in 138 cm to 174 cm.

On the basis of spreadsheet for calculating the tag overlap statistic supported by CCAMLR Secretary (COMM CIRC 10/123SC CIRC 10/69), “Jung Woo No. 2” and “Jung Woo No. 3” have achieved 92% and 87% of tag overlap in the 2010-2011 season. In addition, tagging rates of both vessels were 1.09 and 1.04.