| Summary: | Maintenance and Update Frequency: notPlanned Statement: Study sites are located approximately 5 km apart in the Dampier Archipelago on the north-west coast of Western Australia (see large thumbnail). The low-sediment site is located on the leeward side of East Lewis Island, which lies north-west of the high-sediment Hamersley rocks site on the mainland. The coral communities at both sites are small (1.5 to 2 km in length), shallow (<10 m) patch reefs that are isolated from other reefs within the Archipelago. - Sediment collection - Fungia fungites was common at both sites, although the abundance of its life-history stages were very different. The most obvious physical difference between the reefs was their level of sedimentation. A comparative measure of sediment deposition was obtained by deploying 8 sediment traps (height 30 cm × 5 cm diameter) at each reef, for a total of 87 days. Sediment traps were deployed for a period of 7 to 14 days, every 4 to 6 months, between September 1997 and March 2000. At each collection, the sediment samples were washed through 2 mm sieves, excess water was decanted and the sediment dried at 120°C for 3 days before weighing. - Polyp collection - At each site, 4 locations separated by 100 m were sampled along a transect parallel to the shore. At each location, 30 of the closest polyps to co-ordinates generated from random number tables were collected from within a 1 m2 area. A total of 120 specimens were collected from each of the 2 study sites. Specimens were classified into one of 3 life-history stages: free-living polyps, buds on parent polyps, or sexual recruits. Descriptive information such as fusion between polyps, partial polyp mortality and polyp size (cm diameter) were also recorded. An additional 60 buds were collected to confirm that they were asexually derived, and not wholly or partly due to the settlement of sexual larvae onto polyp skeletons. Within each of the 4 locations at the high-sediment site, 3 buds were collected from 5 different parent polyps. All ...
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