Latitudinal variation in macroalgal consumption by fishes on the Great Barrier Reef

A significant decline in macroalgal consumption by herbivorous fishes from north to south along the Great Barrier Reef (GBR) was identified, driven primarily by behavioral changes in four dominant species rather than biomass or density differences. Despite consistent dominance by Naso unicornis, Kyphosus vaigiensis, Siganus doliatus, and S. canaliculatus—accounting for over 85% of bites across regions—their feeding rates dropped by an order of magnitude in the south. This study highlights that even structurally similar herbivore communities can have vastly different functional impacts on reef ecosystems due to localized behavioral variations.

Bennett, S., & Bellwood, D. (2011). Latitudinal variation in macroalgal consumption by fishes on the Great Barrier Reef. Marine Ecology Progress Series, 426, 241–252. https://doi.org/10.3354/meps09016