Title: Evaluation of the effects of the multi-annual plan on the stock
Authors: SCOTT ROBERTKEMPF A.ULRICH RESCAN C.HOLMES S.EERO MargitSCHON P.-J.
Publisher: International Council for the Exploration of the Sea
Publication Year: 2011
JRC Publication N°: JRC66748
URI: http://www.ices.dk/workinggroups/ViewWorkingGroup.aspx?ID=562
http://publications.jrc.ec.europa.eu/repository/handle/JRC66748
Type: Articles in books
Abstract: The plans objectives are defined in terms of fishing mortality reductions. In the case that there is an accepted assessment (North Sea cod), it is evaluated if the fishing mortality has reduced as intended since the implementation of the plan. Exploitation rates were inspected using the latest assessment, and compared to the fishing mortal-ity in 2004 (2005 start of the implementation of the old cod recovery plan; EU 2004)) and 2008 (2009 start of the implementation of the new cod management plan; EU 2008)) respectively. In cases where no reliable fishing mortality estimate is available from analytical assessments (Kattegat Cod, Cod West of Scotland, Irish Sea cod), only proxies such as biomass trends were used to judge whether biomass is above biomass trigger levels as specified in the regulation. In addition to the biomass proxies, changes in the productivity and recruitment success were evaluated for all four stocks. In a second step, the focus was on the implementation details causing the deviations from the plan. In order to elucidate the source of the deviations from the plan, several analyses were carried out for the four stocks: Estimation of the difference between the TAC advice according to the plan based on the historic assessments and forecasts and the actual TAC decided by the council. It was elucidated what the TAC decided by the council implies in terms of predicted F and SSB developments according to the short term forecasts used as basis for advice and final decisions. For this purpose we analysed ICES advice option tables. If the TAC was in between two options presented, a linear interpolation was used. Analysis on whether the catches were limited by the TAC (which in effect only limits landings) as expected. To this end it was analysed how the proportionality between the different sources in the catch (discards, landings, unaccounted removals) changed over time. Analysis on whether assumptions and results from the short term forecast on which the advice was based were consistent in retrospect or whether they have contributed to the deviations from the planned exploitation.
JRC Institute:Institute for the Protection and Security of the Citizen

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