Friday, March 25, 2011

Marine Stewardship Council - Acceptable time frames for rebuilding depleted fish stocks

In the fall of 2010 MSC consulted with partners and stakeholders on acceptable rebuilding timeframes for certification of depleted stocks.  MSC defines a depleted stock as one which has a biomass below BMSY (the biomass that gives maximum sustainable yield) or equivalent target level, but is still above a precautionary limit level. Fisheries on stocks which are depleted can become MSC certified, however certification of such fisheries requires that there be a rebuilding plan in place which leads to the recovery of the stock within a specified timeframe.

The MSC Fisheries Assessment Methodology addresses rebuilding under Performance Indicator PI 1.1.3.  Currently, a conditional pass score of SG60 merely requires “reasonable expectation of success” with regard to rebuilding to the target biomass of BMSY within a specified timeframe.  

An unconditional pass of SG80 requires evidence that rebuilding strategies “are rebuilding stocks, or it is highly likely based on simulation modelling or previous performance that they will be able to rebuild the stock within a specified timeframe”.

A perfect score of SG100 requires that “strategies are demonstrated to be rebuilding stocks continuously and there is strong evidence that rebuilding will be complete within the shortest practicable timeframe”.

It is good that MSC is considering revising its methodology with regard to depleted stocks; however the consultation document only addresses a clearer definition of the timeframes for rebuilding to be associated with each of the three scores.

MSC certification of fisheries on depleted stocks as “sustainable” is highly controversial.  See for example the ongoing saga of the conditional certification of the fishery on the collapsed offshore South African hake stock. 

It can be argued that the current SG100 requirement should be the minimum required in order for a fishery to be considered for a conditional pass score (SG60) and that an unconditional pass score (SG80 or 100) should only be given to a fishery on stock that has already rebuilt and is fluctuating around BMSY or above under a fishing mortality of FMSY or lower (the fishing mortality rate consistent with maintaining the stock at BMSY or above).

A fishery on a depleted stock should never be considered sustainable.   


  1. Surely if a stock is already rebuilt PI1.1.3 would not be considered.

  2. Fascinating story,The certification of such fisheries requires that there be a rebuilding plan in place Cool!