Stocks mature at ages two through five and begin their return migration to the spawning grounds. Maturation rates are stock and age specific. The mature fish in each cohort are called the terminal run.

TermRun(s,a) = (OcnRun(s,a) - PreTermMort(s,a))MatRt(s,a) [4.2]

where

• TermRun(s,a) = terminal run for stock s, age a
• PreTermMort(s,a) = preterminal fishing mortalites for stock s, age a (over all fisheries)
• MatRt(s,a) = maturation rate for stock s, age a.