Busy Fisheries August in Majuro / by Francisco Blaha

Majuro (Republic of the Marshal Islands) is not an international hub in most aspects, but if you care about tuna science in the pacific, it's the happening place, during the first 2 weeks of August. 

 Is hard to get lost in Majuro...

Is hard to get lost in Majuro...

From the 1 to the 5, the Pacific Islands Fisheries Forum Agency (FFA) has its Science Working Group, in prep for Western and Central Pacific Fisheries Commission (WCPFC) Scientific Committee 10. At the same time (from the 2-4) PNA (that is based there) has it’s meeting on Target Reference Points and Harvest Control, and then from the 6 to the 14, WCPFC SC 10th regular session there. 

All WCPFC member countries get together and discuss the tons of papers and scientific reports provided to them in function of the priorities and requirements agreed in prior sessions. 
It is a complex process and dense process, and while I’m not there (I’m on the training/implementation side) reading the documents presented always enriches my knowledge. 

From the many in this session, I really liked one of the most challenging and innovative presented, that has the authorship (among others) of two collages and friends whose brains and work ethic I really admire, Carola Kirchner and Richard Banks

Carola has been working on a Bioeconomic Model for tuna fisheries to assess potential economic outcomes under alternative management options; as globally, the value of including economic information in the management of fisheries is being increasingly recognised. 

For most fisheries, the long-term maximum economic yield (MEY) that can be achieved occurs at higher biomass levels than the long-term maximum sustainable yield (MSY), therefore providing a buffer against scientific uncertainties to help ensure ecological sustainability of the resource as well as providing higher economic returns.

Her paper proposes a model that will allow both an examination of management limits that maximize a specified economic outcome (e.g., fleet profitability), and a comparative analysis of economic outcomes by gear for any set of management options. Also, the model allows for the analysis of biological consequences of fishery conditions that achieve various economic outcomes.

 Downtown action...

Downtown action...

She uses the results of the  2014 MULTIFAN-CL stock assessments for bigeye, skipjack and yellowfin tunas and the 2012 assessment for south Pacific albacore as the basis of the biological and fishery dynamics. For the economic component, the net present value (NPV) of profits is calculated over a 20-year time horizon in order to provide a measure of the relative economic outcomes of different management options. 

In the projections, effort for four defined fisheries – tropical longline, southern longline, and associated (fish aggregation device - FADs and floating log sets) and unassociated (free-school sets) purse seine – was varied individually between +25% and -50% of 2012 levels. Future recruitment was assumed to follow the long-term spawner-recruitment relationship. 

Some examples of the types of patterns they found in these preliminary results include:

  • Catch revenue can be expected to fall under 2012 effort levels, with southern and tropical longline fleets becoming unprofitable. Profits are predicted to exist only in the purse seine fishery;
  • There is scope for increasing profits through reductions in effort. 
  • Increased stock sizes are expected to increase profits through increased catch per unit effort, but this conclusion is based on standard catch / abundance relationships and developing alternative models of the relationship between abundance and fishing success will be crucial to determining robustness of results; and
  • Positively, the abundance of all four species is predicted to increase under scenarios that maximize NPV of profits.

As the bioeconomic model is further developed, there are many applications and extensions that could be possible, e.g.:

  • Economic evaluation of the trade-offs between FAD and free school fishing approaches within the purse seine fishery;
  • The incorporation of additional economic strata so that the model reflects not just the fishing fleets but other economic units such as coastal states within whose EEZs fishing activity takes place and who gain economic benefits from the selling of access rights and/or on-shore processing and other related industries. 

I find this kind of work very progressive and hopeful, as decision are made in base of money, so proving that fishing “better” can provide more benefits that just fishing “more” is the way to go.

I hope that the delegates at the SC10 consider the inclusion of this work in the scientific research plan of the Committee, and to encourage industry collaboration to ensure the most accurate economic information is available for inclusion.