The effect of parental acclimation to spawning salinity on the survival of larval Cynoscion nebulosus

The yolk and oil depletion of eggs and larvae of spotted seatrout Cynoscion nebulosus, produced by fish collected from two bays with historically different salinity regimes (Matagorda Bay (MB; 18-24%) and Upper Laguna Madre (ULM; 40–50%), Texas, U.S.A. and spawned in salinities of 20, 30 and 40%, differed in their response to both salinity and history. Time to 90% yolk depletion was significantly longer for low salinity bay fish (MB) kept at 20%, but not for high salinity bay fish (ULM) at 20%. The neutral buoyancy salinity of 1 and 2 day old MB 20% larvae was significantly lower than that of MB larvae spawned in 30 or 40%. Overall, eggs and larvae spawned by MB fish were able to hatch out and survive to 3 days post-hatch in lower salinities than those from ULM. Furthermore, the tolerance of eggs and larvae to very low salinities increased with decreasing spawning salinity. The ability of 1–9 day old ULM, but not MB, larvae to survive 18 h exposure to salinities above or below that of spawning exhibited an age-dependent pattern with day 3 being the most sensitive. This study shows that the response of spotted seatrout eggs and larvae to changes in salinity is dependent upon the spawning salinity of the adults and the prevailing salinity regime within the bay.