Data from: Controlled out-of-season spawning of reef-forming corals using offset environmental cues

The global climate crisis has heightened the urgency for developing
interventions to enhance resilience and recovery of coral reef ecosystems.
However, research programs are often bottlenecked by availability of coral
early life stage material due to the annual nature of coral mass spawning.
We present a proof-of-concept of “out-of-season” spawning, utilising
aquarium control technology to induce spawning in multiple Great Barrier
Reef (GBR) corals held in long-term indoor aquaria. By applying a 6-month
offset environmental profile encompassing seasonal temperature,
photoperiod, and lunar cues, we induced synchronised coral spawning during
austral autumn/winter between 2022-2023. We also “phase-shifted” the hour
of sunset by four hours on spawning nights, creating a more favourable
time window (i.e., minimising late nights) for gamete fertilisation.
Spawning occurred on comparable nights after full moon (NAFM) and at
similar times after sunset (TAS) to wild conspecifics, with 2023 cohorts
showing the closest alignment. Gamete fertilisation was successful for six
species: Acropora millepora, Acropora loripes, Acropora hyacinthus,
Acropora elseyi, Acropora austera, and Montipora aequituberculata
producing ~1.8 million larvae. We outline physiological insights into
environmental regulation of coral spawning synchronicity and discuss the
potential for out-of-season spawning to accelerate coral research and
enhance reef restoration programs.