Figure 1.
Map of Moorea showing different habitat types.
Map of the island of Moorea with locations of sampling sites (LTER 1–LTER 6) and schematic illustrating the 3 habitat types sampled at each site. Habitat types are delineated with dotted lines; the fringing reef and backreef are located inshore of the reef crest and together make up the lagoon, while the forereef is located offshore of the reef crest. The predominant habitat types within the lagoons of Moorea are coral-based. Fringing reefs are often characterized by contiguous coral, while the backreef consists of a mosaic of small patch reefs separated by sand, rubble, and coral pavement.
Figure 2.
Dynamics (mean ± 95% CI) of (A–C) corallivorous COTS, (D–F) coral and algae, and (G–I) herbivore biomass on the forereef, backreef, and fringing reef habitats at six sites on Moorea. The key for each row of panels is located in the middle panel. Biomass estimates for herbivorous sea urchins on the backreef and fringing reef habitats are not available; abundance data are presented in Fig. S1.
Figure 3.
Results of herbivore exclusion experiment.
(A) Box and whisker plot of percent cover of erect algae on tiles exposed (Uncaged and Cage control) and unexposed (Caged) to ambient grazing by herbivorous fishes (n = 10). Erect algae were predominately macroalgae (63%), but also include mats of articulated coralline algae (26%) and the cyanobacteria Symploca hydnoides (11%). Boxes are medians with 25th and 75th quartiles. Whiskers are the 10th and 90th percentiles, and dots show the range of the data. (B) Tiles from a cage control (left) and a cage (right, covered with the macroalgae Padina boryana) from the same experimental block.
Figure 4.
(A) Temporal pattern of abundance (mean±95% CI) of parrotfish on the forereef. (B) Box plot showing changes in the median size of parrotfish on the forereef. Lines are the median size and boxes encompass the 25th and 75th percentiles. Sample sizes are given above each box.
Figure 5.
Ontogenetic patterns of habitat use for the two most abundant species of parrotfish.
Size frequency distributions for (A–C) Chlorurus sordidus and (D–F) Scarus psittacus on the forereef, backreef, and fringing reef. Data are pooled from all sites and years.
Figure 6.
Association between juvenile parrotfish and the coral Porites rus.
(A) Mean (±95% CI) number of juvenile parrotfish (C. sordidus and S. psittacus) observed at fringing reefs with high (n = 3) and low (n = 3) cover of the coral Porites rus. Analyses were conducted on log transformed data; means and error bars are back-transformed. (B) Box and whisker plot showing the distribution of coral cover values at the three sites with high and low levels of Porites rus for each of the five survey years. Boxes are medians with 25th and 75th quartiles. Whiskers are the 10th and 90th percentiles, and dots show the range of the data.