The Ministry for Primary Industries is consulting on increasing the Total Allowable Commercial Catch for southern bluefin tuna in the current fishing year and again in 2014–15.

The fishery and current allowances

Management of southern bluefin tuna (STN) throughout its range is the responsibility of the Commission for Conservation of Southern Bluefin Tuna (CCSBT) of which New Zealand is a founding member.  Japanese longliners were catching 1000s of tonnes of STN a year in New Zealand waters (1960s to 1980), mostly prior to the establishment of the Exclusive Economic Zone (EEZ). There was a small recreational fishery based out of Fiordland and STN are taken as a by-catch of the Pacific bluefin fishery out of Greymouth and Hokitika.  On introduction to the QMS a recreational allowance was set at 4 tonnes, customary allowance at 1 t and other sources of fishing related mortality at 2 t. The TACC was increased last year to 817. The reported catch worldwide was around 13,000 t for a long time. CCSBT agreed to reduce global catches by 20% in 2010 to 2012 (to 9,449t) but has increased this over the last 2 years.

The Fish

They can live to 30 years old and reach maximum size of about 190 cm and 140 kg by 20 years old. (The recreational all tackle world record is 158 kg from BOP).  Most STN are mature by 12 years of age. Southern bluefin tuna consist of a single stock primarily distributed between 30ºS and 45ºS, and spawn in the Indian Ocean south of Java around March.  1999 to 2002 seemed to be particularly bad spawning years with better numbers now showing in NZ from more resent spawning seasons. Spawning stock size estimated in the last stock assessment is about 5% virgin biomass, well below Maximum Sustainable Yield (MSY).

The Proposals

The initial CCSBT allocation for NZ was 1000 t, however 580 t of this was given up in the 1980s to assist with stock rebuilding on the understanding that NZ would have priority to have this returned when the stock increased. It was agreed that the nominal 1000 t NZ allocation would be restored in 2010.  The annual CCSBT meeting in October 2011 adopted a science-based management procedure that is designed to respond to the latest information on stock status and recommend appropriate global catch limits that will allow the southern bluefin tuna spawning stock to rebuild to 20% of its unfished level by 2035.

In October 2013 CCSBT agreed to confirm the global catch limit for 2014 at 12,449 tonnes and to set the TAC for 2015 to 2017 at 14,647 tonnes in accordance with recommendations from its scientific committee.

The Ministry for Primary Industries has put one proposal to the Minister (no options are offered other than rejecting the proposal) to increase in the Total Allowable Commercial Catch of southern bluefin tuna for the 2013–14 fishing year from the current level of 817 tonnes by 69 t additional in season Annual Catch Entitlement (ACE); and to set the 2014-15 TAC for STN 1 to 1,000 tonnes (the CCSBT allocation for New Zealand for that year), with effect from 1 October 2014.

  Issues to address in a submission

• It is the CCSBT that decides the global management measures required for STN and have agreed to management procedure based on commercial catch rates.
• However, this stock has been in a severely overfished state for many years.
• What are the principles that should be applied to overfished stocks.  NZ has a Harvest Strategy Standard that says if the stock is assessed below quarter BMSY or 10% virgin biomass then the fishery should be closed.
• The Standard makes exceptions where a national allocation has been determined as part of an international agreement.
• STN TACs are set under section 14 which states if the Minister decides that “the purpose of the Act would be better achieved” he may change a TAC as long as it will maintain the long term viability of the stock. (Not as in Section 13 which requires the stock to be restored to or above a level that can produce MSY).  Does the proposed change meet these criteria?
• Everyone accepts that this stock has been in a bad way for a long time but has improved recently.  There is no new stock assessment until next year.
• There is no proposal to increased recreational allowance.  Currently most of this allowance is uncaught and those fish remain in the water.
• There is very little overlap between the STN longline fishery and the summer sport fishery for marlin, or the winter fishery for Pacific bluefin.  Will expansion on the STN fishery lead to expansion in longlining on other species?
• The 17 day consultation period is very tight.  MPI may believe that submissions will repeat the views of previous years, as very little new information has been supplied in the IPP available here: http://www.mpi.govt.nz/Default.aspx?TabId=126&id=2076