Duwan, E.

Coral reefs are undergoing phase shifts becoming dominated by algae rather than live coral. Algae on reefs is greatly impacted by herbivores such as parrotfish that use both the reef and shallow intertidal zone to feed. These two habitats are unique with differences in algal cover and algal community composition. The shallow intertidal may have greater risk of predation from ospreys and the habitat is more extreme in terms of turbulence and constantly changing microenvironments. It is unknown if feeding in the shallow intertidal zone provides a benefit that offsets the risk of feeding there. This study observed initial and terminal phases Sparisoma viride and Scarus taeniopterus to determine if there are differences in feeding by parrotfish between the shallow intertidal and the reef crest. The main goals of the study were 1) to compare algae from the shallow (higher predation risk) habitat to algae from the deeper (lower predation risk) habitats and 2) to compare abundance of terminal phase and initial phase. Transects at two different depths of 0.5 m and 10 m were placed at 10 different sites on the leeward side of Bonaire, Dutch Caribbean. Point intercept surveys and dry weight of algae samples were used to compare algal cover and fish surveys were conducted to measure parrotfish. Although the shallow intertidal zone had greater algal cover there was not a significant difference in abundance of parrotfish during either developmental stage studied, which may be explained by greater

This student research was retrieved from Physis: Journal of Marine Science XII (Fall 2012)19: 33-38 from CIEE Bonaire.