Changes in coral cover

Changes in coral cover along the GBR, across the GBR, and with depth. Distance along the reef ranges from 0 at the southern end of the GBR to 1 at the far northern end (corresponding degrees in latitude are given in brackets). Distance across takes the value 0 on the coast and 1 on the 80 m contour of the outer shelf. Hard coral cover was rated as follows: 0 = 0%, 1 = 1–10%, 2 = 11–30%, 3 = 31–50%, 4 = 51–75%, 5 = 76–100%). The short dashed lines along the x-axis indicate the location of the survey sites.