Influence of Skipped Spawning and Misspecified Reproductive Schedules on Biological Reference Points in Sustainable Fisheries
نویسنده
چکیده
—During the spawning season, adult striped bass Morone saxatilis can occur outside known spawning tributaries. This phenomenon has been observed in other fishes, suggesting that investigators have misspecified reproductive schedules by assuming annual spawning. Across a range of species, skipped (i.e., nonannual) spawning is positively correlated with longevity. Therefore, reproductive schedules that are misspecified due to skipped spawning or poorly known age at maturation are likely for many moderately to extremely long-lived species. To explore the relevance of misspecified reproductive schedules on sustainable fisheries, a range of types of skipped spawning was modeled for the Chesapeake Bay striped bass population to test for effects on the biological reference point of egg production per recruit. The influence of misspecified reproductive rates was minor, particularly in relation to the effects of the two alternative size limits (46 and 71 cm) that are most commonly used in fisheries management. Among misspecification scenarios, reduced frequency of spawning later in life had the largest effect on reproductive rate. As fisheries management increasingly focuses on thresholds that promote resiliency, increased recognition of variation in reproductive schedules will probably place greater emphasis on conservation of age
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