The distribution and abundance of reef-associated predatory fishes on the Great Barrier Reef

Predatory fishes are important components of coral-reef ecosystems of the Great Barrier Reef (GBR) through both the ecological functions they perform and their high value to recreational and commercial fisheries, estimated at $30 million in 2014. However, management of GBR predatory fish populations is hampered by a lack of knowledge of their distribution and abundance, aside from that of the highly targeted coral trout (Plectropomus spp. and Variola spp.). Furthermore, there is little information on how these fishes respond to environmental stressors such as coral bleaching, outbreaks of coral-feeding starfishes (Acanthaster planci) and storms, which limits adaptive management of their populations as the frequency or severity of such natural disturbances increases under climate change. Here, we document the distribution and abundance of 48 species of reef-associated predatory fishes and assess their vulnerability to a range of natural disturbances. There were clear differences in predatory fish assemblages across the continental shelf, but many species were widespread, with few species restricted to either inshore or offshore waters. There was weak latitudinal structure with only a few species restricted to either the northern or southern GBR. On the whole, predatory fishes were surprisingly resistant to the effects of disturbance, with few clear changes in abundance or species richness following 66 documented disturbances of varying magnitudes.