For stocks of species that can be aged, average weights and lengths for each age shall be estimated at a precision level 3, up to such an age that accumulated landings for the corresponding ages account for at least 90 % of the national landings for the relevant stock.

For stocks for which age reading is not possible, but for which a growth curve can be estimated, average weights and lengths for each pseudo age (e.g. derived from the growth curves) shall be estimated with a precision of level 2, up to such an age that accumulated landings for the corresponding ages account for at least 90 % of the national landings for the relevant stock.

For maturity, fecundity and sex ratios, a choice may be made between reference to age or length, provided that Members States which have to conduct the corresponding biological sampling, have agreed the following:

  • For maturity and fecundity, calculated as proportion of mature fish, precision of level 3 must be achieved within the age and/or length range, the limits of which correspond to a 20 % and 90 % of mature fish;
  • For sex ratio, calculated as proportion of females, precision of level 3 must be achieved, up to such an age or length that cumulated landings for the corresponding ages or lengths account for at least 90 % of the national landings for this stock.