Maternal spawning experience and thermal effects on offspring viability of chub mackerel and their influence on reproductive success

Maternal effects on offspring viability significantly contribute to the productivity and resilience of exploited marine fish populations. The temporal trend biomass chub mackerel ( Scomber japonicus ) in western North Pacific showed cyclic fluctuation patterns, but it has been rapidly increasing since 2011. Although there are several assumptions regarding mechanisms population dynamics this species these waters, is a contradiction thermal environmental conditions recruitment success. We explored maternal age and/or previous spawning experience egg traits captive response conditions. Moreover, from relationship between growth rate temperature experienced by fish, temperatures wild specimens were assessed. sizes eggs spawned females aged 1–3 years negatively correlated with temperature, size nutrition significant larger nutrient-rich 2- or 3-year-old (repeat spawners) than those 1-year-old (first-time at given temperature. Such temperature- maternal-age-dependent reflected standard length first-feeding larvae. starvation tolerance larvae after hatching body also evident derived showing longer heights females. Further, grew faster tested temperatures. process ontogenetic development until 25 days positively Meanwhile, estimated ranged 18.0 20.3°C. These findings suggested that opposing responses mackerel, main recruit may be restricted within range available for spawning. discuss reproductive success accordance life history traits.