2.1. Study sitesThe study focussed on five to eight (dependent on the organism) inshore reefs in the Wet Tropics (WT) between Tully and Port Douglas, and five reefs in the Claremont Isles, north of the Princess Charlotte Bay region (PC; Fig. 1). Surveys were conducted on both the windward and leeward sides of the reefs at several depth zones. The eight reefs surveyed in the Wet Tropics were (from south to north) Dunk, Barnards, Russell, Normanby, High, Fitzroy, Double and Alexandra, and the five reefs north of Princess Charlotte Bay were Hannah, Wilkie, Hay, McDonalds and Heath (Fig. 1). All five PC reefs were surveyed for all four groups, whereas of the eight WT reefs, Alexandra Reef was only surveyed for octocorals, Dunk and Double Island were not surveyed for fish and the Barnard Islands were not surveyed for hard corals.All study reefs are located <20km from north to south oriented coastlines at <20m bathymetry. Reefs in WT have been identified as having the highest risk of exposure to agricultural runoff (Devlin et al., 2003), since they experience river plumes every few years from wet tropical catchments with intensive agriculture (Johnstone, Russell-Mulgrave, Tully River), and plumes from the large, dry tropical Burdekin River on a decadal basis. Reefs in PC are exposed to runoff from the dry tropical Normanby and Stewart Rivers, whose catchments are only slightly modified, being dominated by low density cattle grazing, and having received little or no fertilizers and pesticides. Data on the disturbance history from both regions are sparse. In the last two decades some of the WT reefs experienced an outbreak of Acanthaster planci (early1990s), two tropical cyclones (1986 and 1990), and bleaching-related coral mortality (1998), whereas the reefs in PC have probably not experienced A. planci outbreaks, but have been impacted by four tropical cyclones in the last two decades, and bleaching mortality in 2002 (after the surveys reported here were completed). 2.2. Field data
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