Shuya Nakatsuka

Session 6, Talk 5, 19/1/16 @ 1100 hrs

Discussions on the long-term management strategy of Pacific bluefin tuna have only recently started. The unique situation of Pacific bluefin tuna needs to be taken into account in the development of a harvest control rule (HCR) for Pacific bluefin tuna such that (i) Pacific bluefin tuna has been harvested mainly by targeting juveniles and as a result the stock has remained at a low level for a long time but has sustained. (ii) Pacific bluefin tuna is being caught by many different types of fishery and the size range of the catch by each fishery is generally limited. (iii) At least age 0-2 fish are always being caught before their status is evaluated through stock assessments, which makes it difficult to apply a conventional HCR based on assessment results to the fish of those ages. However, it also has a strength in having a lot of operational information, including recruitment indices. In this presentation, we propose an HCR to set a TAC for juvenile Pacific bluefin tuna that secures any given target spawning stock biomass based on recruitment estimates of the cohorts available to fisheries derived from recruitment information from the monitoring results in addition to the assessment results.

Contact: S. Nakatsuka, National Research Institute of Far Seas Fisheries, Japan Fisheries Research Agency, Japan, This email address is being protected from spambots. You need JavaScript enabled to view it.