Report of the Mackerel Working Group

At the 75th Statutory Meeting in Santander, it was decided (C.Res. 1987/2:3:3) that the Mackerel Working Group (Chairman: Mr S.A. Iversen) should meet at ICES Headquarters from 1-9 March 1988 to:

a) assess the status of and provide catch options for 1989 within safe biological limits for the mackerel stocks and management units in Sub-areas lI-VII and Divisions Vllla,b;

b) update the quantitative description of the distribution and relative abundance of juvenile mackerel by season and by as fine an area breakdown as possible, and re-evaluate possible management measures to limit the catches of juvenile mackerel;

c) consider appropriate management units in light of recent developments in the migratory pattern of mackerel;

d) provide quarterly catch-at-age and catch and stock mean weight-at-age data and information on the relative distribution at different ages by quarter for North Sea mackerel for 1987 as input for the multispecies VPA, and provide information on the likely level of Western stock mackerel which are seasonally present in the North Sea.

In a letter from the Chairman of ACFM (3 February 1988), the working Group was also asked to:

a) review the assessment for the Western stock of mackerel in the light of the latest scientific data on egg mortality, atresia, and spawning outside the standard egg survey area and the consequence of these factors upon estimates of the spawning stock biomass;

b) comment on whether the mackerel stock in Divisions Vlllc and IX should continue to be considered by the Working Group on Pelagic Stocks in Divisions VIllc and.IX and Horse Mackerel, or whether it should be handled by the Mackerel working Group.escription not yet available