Fig. 2. (a and b) Average yield per recruit and (c and d) percentage of maximum average spawning stock biomass for sea scallops harvested over a range of direct fishing mortalities for four rotational periods: harvest every year (thick solid line), once every 3 years (dashed line), once every 6 years (dotted line), and once every 9 years years (thin solid line). Results are shown under the assumption of no indirect fishing mortality (Figs. 2a and 2c) and indirect fishing mortality equal to direct fishing mortality (Figs. 2b and 2d).