WCPFC MANAGEMENT OBJECTIVES WORKSHOP Manila, Republic of the Philippines 28-29 November 2012 CHARACTERISTICS OF HISTORICAL POPULATION DYNAMICS OF TEMPERATE TUNAS IN THE NORTH PACIFIC AND IMPLEMENTATION FOR MANAGEMENT

We examined long-term time-series of stock status of temperate tunas in the north Pacific: Pacific bluefin and albacore tunas, and characterized temporal changes of the both stock sizes by comparing with tropical tunas in the western and central Pacific. Generally, the temperate tunas historically experienced considerable fluctuations in stock status over a long period of time, while tropical tunas with shorter exploitation histories showed consistent decreases in stock sizes and increases in catches. Based on these features, we discussed appropriate management strategies such as identification of candidate limit reference points (LRPs) for each tuna stock in the western and central Pacific, and suggested that LRPs based on historical stock sizes might be applicable for temperate tunas in the north Pacific.