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To determine if protogynous species are, as a result of fishing, more likely to suffer reproductive failure than are gonochoristic species, we modeled the production of fertilized eggs in simulated populations of graysby Epinephelus cruentatus. Additionally, we examined the effect of various compensatory mechanisms on maintaining fertilized-egg production despite increasing fishing mortality. These mechanisms included accelerated maturation, accelerated transition to malehood, accelerated growth, and combinations thereof. Protogynous stocks may be far more vulnerable to fishing than are comparable gonochoristic stocks. Stocks exhibiting uncompcnsated protogyny lost reproductive capacity as fishing mortality increased and failed reproductively (egg production less than 1% of that under natural mortality alone) at a lower fishing mortality rate than did gonochoristic stocks. Compensation through conservation of the numerical sex ratio somewhat reduced the impact of protogyny, and compensation through conservation of the cohort male biomass: fecundity ratio erased all effects of protogyny. All the modeled stocks incurred a drastic reduction in reproductive capacity even at moderate levels of fishing mortality. Delaying harvest of a cohort not only provides increased yield per recruit but also reduces the loss of reproductive capacity caused by fishing.

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