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 IMPLICATIONS FOR MANAGEMENT

We examined long-term time series of stock status for the temperate tunas Pacific bluefin and albacore in the north Pacific, and characterized temporal changes in the stock status of both species through comparison with tropical tunas in the Western and Central Pacific. The temperate tunas appear to have historically experienced considerable fluctuation in stock status over a long period of time, whereas the stock status of tropical tunas with shorter exploitation histories are characterized by consistent decreases in stock sizes and increases in catches. Based on these features, we discuss appropriate management strategies such as the identification of candidate limit reference points (LRPs) for each tuna stock in the Western and Central Pacific, and suggest that LRPs based on historical stock sizes are worthy of consideration for temperate tunas in the North Pacific.