1. Size Matters, even with F = Fmsy
Rainer Froese
Brussels, WWF Office, 6th March 2013

3. Maximum Cohort Biomass
Fish reach maximum growth rate at about 2/3 of maximum length
Mortality and growth have coevolevd such that cohort biomass peaks at that size
Here, fish have spawned several times, and a given catch has the least impact on biomass
Froese, R., A. Stern-Pirlot, H. Winker and D. Gascuel Size Matters: How Single-Species
Management Can Contribute To Ecosystem-based Fisheries Management. Fisheries
Research 92: , doi: /j.fishres PDF

4. Different Scenarios for Baltic Cod

5. Bottom Line
For true recover and healthy stocks sensu MSFD, F = Fmsy is not enough
Size at first capture has to be gradually increase towards Lopt ~ 2/3 max length
This will minimize impact of a given catch (kill fewer fish)
Minimze unnatural selection
Restore size & age structure (many big fish)
Improve catches for a given F