Ocean warming induced by climate change is the greatest threat to the persistence of coral reefs globally. Given the current rate of ocean warming, there may not be sufficient time for natural acclimation or adaptation by corals. This urgency has led to the exploration of active management techniques aimed at enhancing thermal tolerance in corals. Here, we test the capacity for transgenerational acclimation in the reef-building coral Pocillopora acuta as a means of increasing offspring performance in warmer waters. We exposed coral colonies from a reef influenced by intermittent upwelling and constant warm-water effluent from a nuclear power plant to temperatures that matched (26 °C) or exceeded (29.5 °C) season-specific mean temperatures for three reproductive cycles; offspring were allowed to settle and grow at both temperatures. Heated colonies reproduced significantly earlier in the lunar cycle and produced fewer and smaller planulae. Recruitment was lower at the heated recruitment temperature regardless of parent treatment. Recruit survival did not differ based on parent or recruitment temperature. Recruits from heated parents were smaller and had lower maximum quantum yield (Fv/Fm), a measurement of symbiont photochemical performance. We found no direct evidence that thermal conditioning of adult P. acuta corals improves offspring performance in warmer water; however, chronic exposure of parent colonies to warmer temperatures at the source reef site may have limited transgenerational acclimation capacity. The extent to which coral response to this active management approach might vary across species and sites remains unclear and merits further investigation.

Sexual reproduction plays an important role in the population and community structure maintenance in scleractinian corals, particularly in growth and development after larvae settlement. Despite this, only few studies have been conducted to monitor the post-settlement growth and development of scleractinian coral larvae. This study aimed to obtain this data by collecting adult Galaxea fascicularis colonies from Weizhou Island coast (21°00′-21°10′ N, 109°00′-109°15′ E) and recording their complete life cycle, from fertilization to recruitment, for one year ex situ. The results demonstrated that G. fascicularis could reproduce sexually when reared in a tank for 2 y. Their embryo produced a "prawn chip" that lacked a blastocoel, indicating that G. fascicularis is a complex coral. Larvae evidently showed association with zooxanthellae four days after settlement and completed metamorphosis after 1 month. The mean diameter of G. fascicularis recruits was 4.74 ± 1.12 mm, and the survival rate was only 5.60% in the rst year, which may be attributed to their competition with algae. To increase their survival rate without the interference of algae, we suggest that the recruits of G. fascicularis be reared ex situ to complete metamorphosis (1 month) and then transferred to the eld. This study improved our understanding of the early life cycle of scleractinian corals.