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Successful reproduction is critical to the growth and persistence of marine fish populations, yet how changes in the environment influence reproduction remains largely unknown. We explored how shifting ocean conditions influenced larval production in four species of long-lived, live-bearing rockfish (Sebastes spp.) in the California Current. Brood fecundity, body size, and environmental information were analyzed from the mid-1980s through 2020. Interannual variation in brood fecundity was greater than 50% in the single-brooding yellowtail rockfish (S. flavidus) and widow rockfish (S. entomelas). Brood fecundity varied less in chilipepper (S. goodei) and bocaccio (S. paucispinis), two species capable of multiple broods per year. In these two species, interannual fecundity variability is more likely to depend on the number of broods produced than on brood size alone. In all four species, brood fecundity was positively correlated with maternal length and body condition. Variable ocean conditions influenced the strength of maternal size effects by year. These results provide evidence for reproductive plasticity and environmental effects on fecundity, with implications for changes in population reproductive potential with climate change.
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Variation in polyandry, reproductive output, and within-brood genetic diversity in a marine snail population across seasons and years
The frequency of polyandry has important implications for effective population size, genetic variation, and reproductive output. Compared to terrestrial organisms with complex social behaviors, the patterns and consequences of polyandry in marine populations are relatively less clear. Here we quantified polyandry in the Florida crown conchMelongena coronain the field under natural settings. We assessed the extent to which additional mates increase genetic diversity within broods, how polyandry relates to female reproductive output, and how consistent patterns are across their 5 mo reproductive season in 2 separate years. We found large variation in polyandry (2 to 19 sires per brood) and reproductive output among females. However, the number of sires per brood was unrelated to reproductive output. The number of sires increased genetic diversity within broods regardless of year or time of season. The number of sires per brood and reproductive output did not vary over the season or among years. Overall, our results show natural variation in polyandry upon which selection could act, but increased polyandry did not lead to females producing more hatchlings, and neither polyandry nor reproductive output increased over time when females could accumulate and store sperm. Any benefits of polyandry in terms of genetic diversity are expected to occur after hatching, if at all, rather than inside the egg capsule. Variation in polyandry could arise because males control mating and polyandry is less costly for females than trying to prevent superfluous matings.
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- Award ID(s):
- 1829867
- PAR ID:
- 10575530
- Publisher / Repository:
- Inter-Research Science Publisher
- Date Published:
- Journal Name:
- Marine Ecology Progress Series
- Volume:
- 734
- ISSN:
- 0171-8630
- Page Range / eLocation ID:
- 65 to 77
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3354/meps14558
