Report of the Study Group on Multispecies Assessment in the Baltic (SGMAB)

The Study Group on Multispecies Assessment in the Baltic (SGMAB) has now come to the end of its life span. SGMAB convened last time in November 2006 and was mainly tasked with: i) update and correct the multispecies database (i.e. catch in numbers, maturity ogives, mean weight at age) for the Eastern and Western Baltic to enable bi-annual key-runs for both areas; ii) develop, apply and validate enhanced multispecies models, e.g. the new Stochastic MultiSpecies model (SMS); iii) explore the effect of heterogeneous distribution of predator and prey on species interactions in the Central Baltic and investigate the need and possibilities to integrate this heterogeneity into multispecies models; and vi) implement and evaluate the suitable medium- to long-term projection methodology for simulation of stock and catch development under different fishery scenarios and management objectives.