Andrew Cole is currently enrolled in a Doctor of Philosophy program at James Cook University. Originally from the south coast of NSW, Andrew migrated to the warmer waters of the Great Barrier Reef in 2003. His research investigates the role of chronic fish predation on the population dynamics and life-histories of reef-building corals. It also explores the potential for chronic predation to exacerbate the effects of global environmental change. This research is being carried out under the supervision of Dr Morgan Pratchett, Prof Geoff Jones and Dr Shaun Wilson.
Interactions between predators and prey are of fundament importance to ecological communities. While the impacts that grazing predators can have in terrestrial and temperate marine systems are well established, the importance of coral grazers on tropical reefs has rarely been considered. The trophic link between corals and fishes is potentially very important to the energetics of coral reef ecosystems. Corallivory is the primary means of incorporating energy derived from corals into higher trophic levels. However, chronic grazing by fishes is also expected to represent a significant energetic cost for reef-building corals, as energy spent in regeneration of grazed tissue is not available for other life history processes such as growth or reproduction. In my thesis I examine the effect that corallivorous fishes have on the coral community by addressing five main objectives: (1) Determine how the predation effort is dispersed both within and among different coral species; (2) Quantify the amount of coral tissue that is removed per bite by coral-feeding butterflyfishes; (3) Determine what proportion of coral tissue is removed from the reef at the population level and assess whether this consumption represents a significant proportion of the annual productivity of corals; (4) Quantify the energetic cost of chronic fish predation on coral growth, condition and reproductive output by undertaking a long term removal experiment and (5) Quantify the impact that newly settled obligate coral feeders have on the corals they inhabit. While corallivory is not the primary cause of coral colony death, it can be a significant contributing factor in coral mortality when prey corals are also exposed to increasing levels of anthropogenic stresses such as climate induced coral bleaching events.