There are two stocks for Japanese jack mackerel. The Pacific stock is said to be overfished while the Tsushima warm current stock seems to be in better condition, and stock appears to be appropriately used.
Details on whether retained catch contain juveniles or non-target species is lacking. Although discards may be moderate in Japan, discards relating to this fishery are deemed to be low. Purse seine is a selective fishing gear and all small pelagic are main target species for purse seiners. The mortality of slipped fish tends to be high. Significant ecosystem changes caused by this fishery are unlikely. Purse seine have no impact on the bottom habitat.
This fishery is run by Japan’s Ministry of Agriculture, Forestry and Fisheries (MAFF). Information on endangered, threatened, protected (ETP) impacts is limited due to the non-requirement for Japanese fishing vessels to monitor encounters with ETP species. The transparency of this fishery is moderate, with most of the information available online. Overall management is partly effective.