Note on potential indicators of the Japanese longline fishery targeting bluefin tuna in the Atlantic

This paper proposes a more active use of various fishery indicators showing the changes observed in the Japanese longline fishery targeting bluefin, a fishery that is of major importance in the studies of this stock. The paper first reviews various types of geographic indicators, based on ad hoc fishing maps and pie diagrams showing the main characteristics and changes in this fishery. The main indicators studied are measuring the efforts targeting bluefin using three methods, the corresponding CPUEs and the sizes of the area fished, yearly and monthly. The large anomalies observed during 2009 in this bluefin fishery should be further analyzed in 2010 based on the finalized catch and effort data set.