Based on ICES (2000), Table 2.2.2.6, Catches of mackerel by Division and Sub-area in 1999, p. 56.
Age cohorts
Following the biological modelling of mackerel by ICES (2000), there are 13 year classes of mackerel  , with the four age-12 classes for each season including fish aged 12 and above. Fish numbers are tracked across seasons s within each year y, in line with constant natural mortality m, and seasonal across-cohort fishing mortality set by the j-th harvester, . The number fish in millions in cohort a in year y in season s is denoted  .
Share with your friends: |
