Correction to Estimate of 2012 Recruitment due to Delayed Survey Start Date

At a meeting on the 30th May 2012 the Small Pelagic Scientific Working Group (SPSWG) agreed that the sailing date of the 2012 recruit survey should not be postponed beyond the 12th June (FISHERIES/2012/MAY/SWG-PEL/Aide Memoire 30th May). The reason was that all recruit surveys conducted since the inception of a management regime using OMPs 20 years ago, had commenced no later than the 10th of June. It was also necessary to inform DAFF management and the South African Navy of a cut-off date for sailing so as to prevent the start of the survey from being further postponed in the event that mechanical or operational problems arose. This deadline date was communicated to DAFF senior management on the 31st of May (DAFF internal submission). When it later became apparent that the SAS Africana would be able to sail only on the 14th June, however, the chair of the SPSWG advised DAFF senior management that such a further delay would be acceptable and preferential to a no-survey scenario, and further that a method to adjust the survey estimate for such further delay would be developed. This document recommends a small adjustment to the survey estimate of recruitment that is to be input to the OMP TAC formula, to take account of the additional uncertainty associated with the implicit extrapolation that using survey results affected by this delay involves.