CPUE and proportional recruit indices from Japanese krill fishery data in Subarea 48.1

Proportional recruit indices and CPUE in Subarea 48.1 (Antarctic Peninsula region) from 1980 through 1996 were calculated based on the log book data from Japanese commercial krill trawlers. Proportional recruits calculated from fisheries data showed similarity with those from scientific data (Siegel et al., 1997), and showed close relationship to sea ice indices. CPUE (catch/towing volume) in Livingston area showed a decreasing trend during the study period. Alternation of operational strategy in relation to the product quality and decrease of krill density in the areas were considered as the possible reasons. On the other hand, CPUE in Elephant area showed greater inter-annual variation without any trend.