Herbivores play a key role in the maintenance of algal and coral communities. A reduction in herbivory has been shown to result in a shift to a macroalgae dominated system, which can have significant effects on the biodiversity and restorative capabilities of coral reefs. Several studies have been done to better understand how herbivorous communities respond to macroalgae. These have shown that only certain herbivorous taxa are capable of removing macroalgae and there are several factors (depth, density, etc.) that affect the susceptibility of macroalgae to herbivory. However, few studies have yet to determine if the novelty of the resource will affect how herbivorous fish communities respond to a macroalgae phase shift. This study examined the existence of a novelty response at both a community and species level at a mid-shelf reef in the Great Barrier Reef, using macroalgal arrays and aquarium. The macroalgal arrays, of Sargassum, did show a delayed response, however the tank experiments of a herbivorous species (Siganus doliatus) did not exhibit any change in preference of the familiar and novel food over time. The lack of a novelty response in the species suggests that the delayed response exhibited by the herbivorous fish community was due to the time it took the fish to find the new resource. This means that the response of herbivorous fish communities that have never experienced macroalgae should be comparable to communities with similar fish compositions that have experienced macroalgae before.
Biodiversity | Ecology and Evolutionary Biology
Pickens, Christopher, "Novelty Interactions Between Herbivorous Fish and Sargassum: Insight into Macroalgal Phase Shifts" (2012). Independent Study Project (ISP) Collection. 1483.