CPUEs and body length of Antarctic krill density during the 1997/98 season in Area 48

This paper summarizes the Japanese krill catch data during austral summer through winter of 1997/98 season in the Area 48. The fishing grounds were formed around the South Shetland Islands, west of the Antarctic Peninsula, and around the South Orkneys Islands from mid-December to mid-May. From late May till late June, the operation took place in the north of the South Shetland Islands and north east of South Georgia. Size composition differed among the areas. In the west of the Antarctic Peninsula, the modal size was approximately 50mm, with narrow size range. Around the South Shetland Islands and the South Orkneys Islands, the size range was from 30 to 50mm, and their modal size differed among the periods. In the north east of South Georgia, single mode (approx. 37-39mm) with narrow range was observed. Variations of CPUEs were dramatic for some vessels, but there was an increasing trend across time. The main reason for the variations of the CPUE among the vessels were thought to be due to the difference of the fishing ground.