Fig. 1. (a) Yield per recruit and (b) percentage of the maximum spawning biomass per recruit (when F = 0) for sea scallops at different levels of direct fishing mortality under the assumption that (i) there is no indirect fishing mortality (solid line), (ii) there is indirect fishing mortality on prerecruits only (dotted line), and (iii) there is indirect fishing mortality on all ages (dashed line). Indirect fishing mortality is assumed to equal the direct fishing mortality. Note that the direct fishing mortality resulting in maximum yield per recruit is much lower when indirect fishing mortality occurs (Fig. 1a).