Examining productivity changes within the tropical WCPO purse seine fishery

The Western Central Pacific Ocean (WCPO) is one of the most productive tuna fisheries in the world and catches by weight of tuna are dominated by the purse seine fleet. The tropical WCPO purse seine fishery is primarily managed through effort limitations (limits on the number of fishing days per year). However, constant innovation leading to more efficient ways to find, catch and process fish, can result in an increase in productivity e.g. the amount of catch per fishing day . Increasing fleet productivity is a key feature of concern in effort/input controlled fisheries, as it can have detrimental effects to health of the stock if not properly accounted for.