Hidden Giants: The Story of Bolbometopon muricatum at Ningaloo Reef

Scientific surveys at Ningaloo Reef have revealed the first recorded presence of Bolbometopon muricatum (bumphead parrotfish) since 1989. Researchers documented 155 individuals across 63.2 hectares, indicating a mean density of 2.38 fish per hectare. This discovery suggests that B. muricatum has likely been present in ecologically significant numbers at Ningaloo since 2006. The study estimates these fish remove approximately 13.42 tonnes/ha or 1.34 kg/m² of calcium carbonate annually, comparable to parrotfish bioerosion rates in other central Indian and Pacific Ocean reefs. Despite their ecological importance as ecosystem engineers and keystone species, B. muricatum lacks elevated conservation status in the Ningaloo Reef Marine Park, warranting reconsideration due to their vulnerability to overfishing.

Thomson, D. P., Cresswell, A. K., Doropoulos, C., Haywood, M. D. E., Orr, M., & Hoey, A. S. (2021). Hidden Giants: The Story of Bolbometopon muricatum at Ningaloo Reef. Fishes, 6(4), 73. https://doi.org/10.3390/fishes6040073