Albacore tuna is an important species for all commercial, customary and recreational fishers. It is a highly migratory pelagic species found mainly on the western coasts of the North and South Islands of New Zealand, as well as in the South Pacific Ocean.
Mature fish spawn in tropical and sub-tropical waters, between about 10⁰S and 25⁰S, during the austral summer. Juveniles appear in surface fisheries in New Zealand at one year of age, from where they appear to gradually disperse to the north and migrate south during early summer and north during winter.
The species is not part of the NZ quota management system but it is closely monitored and managed by international and New Zealand fisheries authorities and management groups such as the Tuna Management Association specifically for troll caught albacore in New Zealand waters. The South Pacific albacore stock is the responsibility of the Western and Central Pacific Fisheries Commission (WCPFC) and Fisheries New Zealand.
The Tuna Management Association, which was formed in 2001, was instrumental in getting the NZ albacore troll fishery certified by the Marine Stewardship Council (MSC) in 2011, re-certified in 2016 and again in 2021 (Certification lasts five years and needs to be re-certified on that basis). MSC has a stringent certification and stock assessment process to maintain sustainable fisheries. Many of you would have seen the MSC symbol, the blue fish tick, on many fisheries products. New Zealand has eight major species/ fisheries with MSC certification.
The use of trolling is a low impact method of fishing and the most applicable for a species that is migratory and follows temperature thermoclines in the water column.
Roughly 90% of albacore tuna caught in New Zealand is caught using this method. A typical coastal albacore troll vessel is between 1520m in length and the fish is packed fresh into ice and delivered to coastal ports from the north to the south.
The commercial troll method uses 12-18 lines simultaneously from the vessel’s stern and from long outrigger poles mounted amidships. The spacing is controlled to ensure that entanglement does not occur but able to be set at the optimal depth. The lines are either braided polypropylene, Dacron or monofilament nylon and are hauled in by hand or by hydraulic haulers.
The movement of the barbless lures resemble the rapid movements of small fish in the surface water, which attracts tuna schools thinking they’re prey. There is very minimal interaction with protected species, given the fishing areas and use of un-baited lures.
Tuna is an important source of Omega-3 fats and selenium, and canned tuna is a lean protein. As with other commercially caught fish and shellfish species, they all form an important part of our protein diet.
Source: Sourcing Transparency Platform
