Home MEETINGS Preparatory Stock Assessment Workshop 2011 Preparatory Stock Assessment Workshop
Friday, 25 March 2011 10:12
preparatory tuna stock assessment-no text

2011 Preparatory Stock Assessment Workshop
SPC, Noumea, New Caledonia
4 – 8 April 2011

The Preparatory Stock Assessment Workshop is a meeting convened by SPC-OFP, usually in April each year, to help prepare for the annual stock assessments being conducted by SPC-OFP for the Western and Central Pacific Fisheries Commission (WCPFC).  The terms of reference for the meeting are:

  • To review the most recent completed assessments, in particular any concerns, suggestions and/or recommendations raised by the Scientific Committee, the Commission, research providers, individual CCMs, or any independent reviews;
  • To review preliminary work undertaken by the service provider (SPC-OFP) relating to the stock assessments, including any proposed:
    • Revisions to biological parameters
    • Revisions to historical data
    • Changes to structural assumptions in the model
    • Methodological issues, e.g. characterization of uncertainty
    • Standardized CPUE analysis
    • Incorporation of tagging data or other auxiliary data
  • To provide guidance to the SPC-OFP on:
    • The suitability of any proposed changes and any suggested additional work
    • A minimum set of model runs to be undertaken, in particular the range of key sensitivity analyses
    • Desired model diagnostics to be presented
    • Alternative modelling approaches that could be considered

The workshop is open to participation by scientific representatives all Commission CCMs and to other experts by invitation. CCMs will be expected to fund their own participation, although eligible CCMs may seek support from the Commission’s Special Requirements Fund or other sources, as appropriate.


Meeting Information

1 - Terms of Reference SPC for 2011 Pre-assessment Workshop  icon (54.16 kB)
2 - Preparatory Workshop for 2011 Tuna Stock Assessments Notice 2  icon (269.02 kB)
Connecting to the Wireless Network (WI-FI) IRD-HotSpot  icon (807.76 kB)
The meeting will be held in the Conference Room #2 on the IRD campus, next to SPC. Participants are advised to meet at SPC reception on Monday 4th at 0820. 2011_map-spc_ird_thumb

Information Papers

Report on Yellowfin tuna in the Western and Central Pacific Ocean  icon (199.49 kB)
Review Stock Assessment of Yellowfin Tuna in the Western and Central Pacific Ocean  icon (625.06 kB)
Report of the 2011 ISSF Stock Assessment Workshop  icon (1.24 MB)
Research outline for size data used in WCPO  icon (31 kB)
Research outline for CPUE data used in WCPO  icon (56.72 kB)
Draft Report WCPFC Limit Reference Points  icon (1.07 MB)
Size data reseach - Recent progress & options for 2011 assessments  icon (5.92 MB)
Sex, Growth, Vulnerability, and Death: alternative hypotheses for tuna sex ratio variation .icon.(56.72 kB)
Proposed approaches for 2011 stock assessments  icon (25.69 kB)

PowerPoint Presentations

Please note that these presentations are preliminary and are subject to change.

Update of Recent Developments in MULTIFAN-CL and Related Software for Stock Assessment  icon (802.8 kB)
Initial YFT Review Response  icon (81.83 kB)
Steepness ISSF  icon (706.11 kB)
A general approach for WCPFC stock assessments  icon (82.54 kB)
MULTIFAN-CL implementation of deterministic and stochastic projections  icon (262.38 kB)
Research outline for size data used in WCPO  icon (233.81 kB)
Research outline for CPUE data used in WCPO  icon (93.33 kB)
WCPO YFT CIE Review  icon (169 kB)
Update on Indonesian and Philippines Data  icon (694.3 kB)
Issues with the Bigeye Tuna Recruitment Trend and MSY-Based Stock Status Determination  icon (1.17 MB)
Purse-Seine Catch Estimates determined from Observer Grab Samples corrected for Size Selectivity  icon (484.5 kB)
A standardized CPUE analysis of the Japanese distant-water skipjack pole-and-line fishery in the western and central Pacific Ocean (WCPO), 1972-2009 (SA WP 8)  icon (1.4 MB)
CPUE analysis methods, progress and plans for 2011  icon (1.81 MB)
PL CPUE work plan of Japan  icon (928.25 kB)
Current approaches to modelling Purse seine CPUE in MFCL  icon (278.9 kB)
Preliminary standardized CPUE - Japan PL DW region 2 & 3  icon (443.2 kB)
Draft Report: Identification of candidate limit reference points for the key target species in the WCPFC  icon (75.09 kB)


Monday, 4th April
Morning (0830-1200)


Participants will be welcomed and the process for the meeting and documenting outcomes discussed


The current status, recent, and future developments will be discussed. This will include the website and current release details.

Catch estimates

  • Indonesia and the Philippines
  • Purse seine catches determined from observer grab samples corrected for size selectivity
Afternoon (1300-1630)

CIE review
SPC will present the recommendations from the 2009 yellowfin tuna assessment review (which will be distributed to participants in advance of the meeting) and their summarised response. More detailed responses will come through in the specific agenda items. A written response will come in the form of a SC7 paper.

Tuesday, 5th April - Wednesday, 6th April
All day (0830-1630)  

Stock assessment inputs

  • Longline CPUE
  • Size data
  • Pole and line CPUE
  • Purse seine CPUE
  • Tagging data
  • Biological inputs

Presentations in each of the above-listed work areas will focus on two aspects

  1. a strategic approach to address the issues in the form of a medium term
  2. research plan;an update on any progress to date.

These planning documents will lay out the different work areas and a suggested timeline.
We will be seeking some comment from the WS on these plans which will then be presented to SC7 for endorsement as documents to direct work in these areas (the Science Manager will need to determine how best to incorporate these into existing planning documents).
The work presented under (b) need not result in changes to the assumptionsfrom previous assessments

Thursday, 7th April
Morning (0830-1200)

Reference points and related issues

  • Report from ISSF steepness workshop
  • CSIRO consultancy on reference points (To be confirmed)
  • Use of temporal windows to estimate spawner recruitment relationships in MFCL

Resulting from these discussions could be suggestions for a range of assumptions to be considered in the assessments. It should be noted that the implementation of the SPC reference point work will be discussed in the context of projections.

Afternoon (1300-1630)

Proposed stock assessment approaches for 2011

During the meeting SPC will update last year’s assessment tables which outline key assumptions / data sources etc. SPC will be seeking input on the runs to be considered. SPC notes that it does not intend to undertake full grids of structural uncertainty analyses for these assessments –the extra time will be needed for the projections and reference point work.

A general approach for WCPFC stock assessments

SPC will present a proposed framework for ‘streamlined’ and full assessments with integrated peer review and the update of conservation and management measures. SPC will be seeking comments from the WS and a decision will then be made as to whether this be developed into a SC7 working paper.

Friday, 8th April
Morning (0830-1200)


  • MULTIFAN-CL implementation of deterministic and stochastic projections

We will first provide an overview of the projection methods used for the evaluation of management options and reference point analyses and then demonstrate the features of TUMAS.

Afternoon (1300-1630)

Review of meeting outcomes

A summary of the key meeting outcomes will be produced for initial discussion if time allows. The full draft report will be distributed within ten working days.

Copyright © 2023 Oceanic Fisheries Programme. All Rights Reserved.
Joomla! is Free Software released under the GNU/GPL License.
   SPC Homepage | About SPC | Copyright © SPC 2010