Effort scenarios consist in sequences e(t0), . . . , e(T ) from current time t0 to temporal horizon T typically 2030, ..., 2050. Important normative scenarios for fisheries management are scenarios that aims at maximizing the intertemporal utility U(h(t)) of catches h(t) or profits π(t) derived from fishing. In the stochastic context, they consist in maximizing the expected present value of fishery returns as follows:
where E refers to the expected value of returns with respect to uncertainties and ρ stands for the discount factor. The first optimal strategy turns out to be related to the MSY (maximum strategy yield) strategy while the second optimal strategy relates to the MEY (maximum economic yield) strategy.Other ecosystem services can be taken into account by refining the utility function U which can also depend on states x(t) of the ecosystem.