Herbivores working over dead, algae covered branching corals. Image: AIMS Long-term Monitoring Team.

What happens to fish on the GBR when their coral homes are devastated by bleaching, crown-of-thorns starfish and cyclones? The surprising answer - from a team of researchers, including scientists from the AIMS Long-term Monitoring Team - has won this year's prize for the best paper in the international journal, Coral Reefs (Coral Reefs 2009 Vol 28: pages 3–14).

"This study examined the effects of habitat disturbances on species richness of coral reef fish assemblages using annual surveys of habitat and 210 fish species from 10 reefs on the GBR," says the paper. "Over a period of 11 years, major disturbances, including localised outbreaks of crown-of-thorns sea star ( Acanthaster planci ), severe storms or coral bleaching, resulted in coral decline of 46–96% in all the 10 reefs". Another 38 reefs in the study that had remained steady or increased their coral cover were excluded from the analysis.

Of the 10 degraded reefs, the paper reports that "Despite declines in coral cover, structural complexity of the reef framework was retained on five and species richness of coral reef fishes maintained on nine of the disturbed reefs. Results of this study clearly demonstrate that a decline in coral cover does not necessarily lead to a decline in structural complexity or species richness of coral reef fishes. Coral cover varied from 0 to 60%, yet species richness of the fish community changed by only 6–8%."The paper does point out, however, that this 6-8% does involve losses to a key group of fish species with a strong dependence on corals for food or shelter.

The team also included scientists from the School of Marine Science & Technology, University of Newcastle, Newcastle-upon-Tyne (UK) and the ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville.