Chub mackerel

Chub Mackerel ( Scomber japonicus) are small, pelagic fish that form large schools based on size and will occasionally form schools with sardines. Chub Mackerel have a longer life (18 years) making them moderately vulnerable to high fishing pressures. The overall stock status in the FAO area 61 and 87 is uncertain with some areas being unknown, overfished and others stable. Stock status in the FAO area 71 cannot be evaluated due of lack of data (the only country with catches is the Philippines).

2. How was it caught or farmed?

Chub mackerel are caught in the pole and line fishery. In this type of fishing, rigid poles (2-3 meters) are attached to a feathered jig containing a barbless hook attached by a short piece of line.

No information is available about catch composition for chub mackerel fisheries in Japanese waters, but as hand operated line fisheries are selective catch methods, high bycatch of nontarget species or juveniles is unlikely. This fishing method has no negative impact on the benthic habitat or surrounding environment.

Chub mackerel are caught using stationary uncovered pound nets. Stationary uncovered pound nets consist usually of net walls anchored or fixed on stakes, reaching from the bottom to the surface. The nets are open at the surface and include various types of fish herding and retaining devices. They are mostly divided into chambers closed at the bottom by netting.

This gear poses a serious threat to marine mammals, especially to the local sub-population of common minke whale. For stationary pound nets, bycatch is unlikely, as unwanted fish can be released. The fishery is considered not causing negative ecosystem changes.

Chub mackerel are targeted or caught as bycatch within the purse seine fishery for jack mackerel. Purse-seine nets are set around a school of fish in the surface to mid-water. Once the school is surrounded the bottom of the net is closed by a footrope.

Current levels of bycatch are unknown as well as the impact on endangered, threatened, or vulnerable species. In addition, there is very little information available regarding the proportion or survival of discarded species. The fishery is not destructive to the habitat.

Chub Mackerel are targeted or caught as bycatch using mid-water trawls. Midwater trawl nets are very large with a minimum mesh size of 75mm when stretched to maximum size. Trawling takes place in the zone between the seabed and surface of the sea and the net is dragged through the water without touching the seabed.

Current levels of bycatch and juveniles for the whole fishery are unknown as well as the impact on endangered, threatened, or vulnerable species. In addition, there is very little information available regarding the proportion or survival of discarded species. There is no known damage to benthic habitats.

3. Where is it from?

Chub Mackerel is fished around the Japan EEZ FAO 61 and imported into South Africa. Chub mackerel in Japan is managed as two separate stocks: the Pacific stock and the Tsushima Current stock. The overall management is partly effective. Although there is no specific management in place for chub mackerel, the fishery is managed through a number of regulatory measures including a Total Allowable Catch (TAC) limit, Total Allowable Effort (TAE), specific mesh sizes, minimum landing sizes and seasonal closures. An Ecosystem based management is currently at the state of implementation.

Chub Mackerel is fished in the FAO region 61 FAO 61 by Japan, Russia, China and Korea and imported to South Africa. Management measures are indicated for fisheries in Japan and Russia. Chub mackerel are managed through a Total Allowable Catch (TAC) limit within the Japanese Exclusive Economic Zone (EEZ) and a multilateral management plan for the waters outside the EEZs is currently being developed. However the effectiveness of the management is currently unknown due to the lack of specific management.

Chub Mackerel is fished in the FAO region 87 FAO 61 and imported into South Africa. During the last years, Chile have upgraded the legal and institutional framework for fisheries, and also im-proved monitoring programmes. However, the effectiveness of management cannot be evaluated due to lack of information.

Chub Mackerel is fished in the FAO region 71 FAO 71 and important to South Africa. No management measures are reported and given the level of uncertainty regarding the stock status; the fishery is assessed as effectively unmanaged. No management measures are in place for this fishery.

Chub Mackerel is fished in the FAO region 87 FAO 61 and imported into South Africa. Some management measures are established, these include mesh size, minimum landing size, seasonal closures. During the last years, Chile have upgraded the legal and institutional framework for fisheries, and also improved monitoring programmes. However, the effectiveness of management cannot be evaluated due to lack of information.