|Southern poutassou, merlan bleu austral (France, Canada), merlu (Italy), blauer wittling (Germany), minamidara (Japan)|
Southern blue whiting ranks as a worst choice seafood. A better alternative is
Southern blue whiting is a deepwater cod species and is only found in waters around the
sub-Antarctic islands, where it schools near the seabed at depths of 450 to 650m. It is therefore targeted and caught as bycatch in bottom trawl fisheries operating in this region, particularly during its spawning season in August to early October.
Southern blue whiting is caught by midwater and bottom trawling. Concerns over this fishery include the unknown sustainability of current catch limits in two stocks and the lack of a management plan. Of particular concern is the capture of nationally critical New Zealand sea lions in this fishery around the Campbell Island. Other concerns include the impact of bottom trawling, the very high bycatch of New Zealand fur seals (the highest of any New Zealand fishery), especially around the Bounty Islands, and the deaths of seabirds, including grey petrel and Salvin’s albatross.
The southern blue whiting fishery is certified under the Marine Stewardship Council (an international body that assesses and awards sustainable fisheries certifications) from April 2012 for 5 years. Forest & Bird disagrees with this given the bycatch, benthic impacts and stock uncertainties.
The southern blue whiting fishery has an export value of about $18.7 million (2015), with the main markets in China (55%), South Africa, Russia and Ukraine. This fish is also used to make crabsticks or surimi with value of $4.43 million, with main exports to Japan (95%) and Thailand.
Regional differences in the sub-Antarctic, specifically Campbell Island-caught southern blue whiting compared to the remainder, were assessed. There was no difference in scores between regions and all southern blue whiting ranks as red, worst choice seafood which should be avoided.
|Score:||All regions – C|
|Population size:||Highly uncertain or unknown for the Pukaki and Auckland Island stocks, depleted for the other two areas.|
|Annual catch limit:||Increased to 53,208 tonnes from 2014.|
|Recorded catch:||Reported landings of 31,887 tonnes in 2014-15.|
|Stock trends:||Campbell Island: “At a TAC of 40,000 t, the biomass of the Campbell stock is expected to decrease slightly over the next 1–2 years.” The Bounty Platform stock is declining: “The biomass of the Bounty stock is expected to decrease over the next 3 years at the current catch level as the 2002 and 2007 year classes are fished down.” Trends of the Pukaki Rise stock and Auckland Islands stock are unknown.|
|MSY Status:||Of the four stocks, Bounty Platform and Campbell Island stocks are declining. The biomass of the Pukaki Rise stock and the Auckland Islands stock is unknown.|
|The Ministry of Primary Industries assessment plenary report includes:|| Campbell Islands stock: “B2014 was estimated to be at or above 50% B0 and is Very Likely to be at or above the target.” “Overfishing is Very Unlikely to be occurring.” “Uncertainty about the size of future age classes affects the reliability of stock projections”.
Bounty Platform stock: “B2013 was estimated to be between 40% Bo and 50% Bo. About as Likely As Not to be at or above the target” “Overfishing is Unlikely to be occurring”.
Pukaki stock: “Current status unknown. Believed to be only lightly exploited between 1993 and 2002. No current reliable indices of abundance (wide area surveys were discontinued in 2000)”.
Auckland Islands stock: Current status is unknown: “No reliable indices of abundance.” (MPI, 2016, p 1343-1350).
|Score:||All regions – D|
|Distribution:||Restricted to sub-Antarctic waters. This species is abundant south of New Zealand on the Campbell Plateau, Pukaki Rise and Bounty Platform at depths of 300-650m.|
|Maximum age (years):||25|
|Age at sexual maturity:||2-4|
|Reproductive output:||Medium to low|
|Ability to recover:||Low to moderate (greatly variable annual recruitment)|
|Score:||All regions – E|
|Fishing method(s):||Southern blue whiting is caught by a mixture of bottom trawling and midwater trawling. Over half of the midwater trawls are fished on or near the bottom.|
|Habitat damage:||Bottom trawling destroys sea floor species assemblages and fragile seamount habitats. It decimates black coral, lace corals, colourful sponge fields, long-lived bryozoans and many other invertebrate species. Bottom trawl impacts include habitat modification, loss of biodiversity, loss of benthic productivity, modification of important breeding and juvenile fish habitat.|
|Habitat of particular significance:|
|Bycatch:||Non-threatened bycatch include other fish such as ling, hake, and hoki and shark species.|
|Ecological effects:||Trawling impacts on bottom-dwelling species and associated communities. Removal of young southern blue whiting, which are an important food for globally threatened yellow-eyed penguin and forms the bulk of the food of globally threatened black-browed albatross (Diomedea melanophrys impavida) during the chick-rearing period (Cherel et al, 1999) could have wider ecological impacts.|
|Bycatch:||The principal protected species incidental captures are of New Zealand sea lions (a critically endangered species), New Zealand fur seals and seabirds. The southern blue whiting fishery captures an estimated 74 New Zealand fur seals, especially around the Bounty Islands (5-year average). Seabird captures are dominated by grey petrels and Salvin’s albatross (which is a threatened species). New Zealand sea lion captures in the Campbell Islands fishery has been estimated to be as high as 24, with an average of 12 annually based on the last 5 years.|
|Management component:||Single species. Management boundaries fit with stock boundaries.|
|Quota Management Species:||Yes, since 1999 (1 November).|
|Management plan:||Deepwater management plan completed but no operational plan and the plan lacks key environmental standards.|
|Stock assessment:||Quantitative stock assessments for all areas except Auckland Islands: Campbell Islands (2011), Bounty Platform (2011), Pukaki Rise (2002). Industry surveys have resulted in variable acoustic results.|
|Research:||Current research focused on Bounty Islands and Campbell Islands stocks. No research on Auckland Islands and Pukaki Rise stocks.|
|Observer coverage:||49% on average over the different fisheries, with 68.5% in the Campbell Island fishery over the last 5 years.|