The polyps of Acanthastrea bowerbanki, like those of other reef-building corals, have a symbiotic relationship with single-celled algae, called ‘zooxanthellae’, which lives within their tissues (3). Both parties gain from this relationship, with the photosynthetic zooxanthellae producing nutrients which nourish the coral polyp, and the coral providing the zooxanthellae with a protected environment and access to sunlight near the waters surface. It is thought that the coral can obtain around 70 percent of its nutrient requirements from this relationship (3). However, this reliance on sunlight for photosynthesis means that corals such as Acanthastrea bowerbanki are limited to living in relatively shallow, clear waters (3) (5).
Coral colonies can generally reproduce both sexually and asexually. The process by which they reproduce asexually is known as budding and involves the coral polyp dividing to form new polyps (3). For reproducing sexually, Acanthastrea bowerbanki is hermaphroditic, meaning each polyp produces both eggs and sperm, which are released into the water for external fertilisation. The age of first maturity for most reef-building corals is approximately three to eight years (6).