| Summary: | Maintenance and Update Frequency: notPlanned Statement: -Study sites- Study sites are located approximately 5km apart in the dampier Archipelago on the north-west coast of Western Australia (see large thumbnail) and their coral communities are located in similar depths of water (3-5 m) on a narrow reef lat with a slight slope and a small drop off to sandy substrata. Apart from these similarities, they differ in a number of physical attributes that reflect their contrasting exposure to disturbances. The Mainland Reef (ML) is adjacent to the mainland, has a low profile, and consists primarily of skeletons of fungiid and massive corals with mush of its free substrata covered by fine sediment. The Mainland Reef is exposed to the predominately westerly and north-westerly winds and waves produced by summer storms, in addition to swell generated by cyclones that travel through Mermaid Sound. The modified effective fetch for the Mainland Reef is 20km and the reef is classified as semi-exposed. Because wind speeds and directions are correlated to wave heights and sedimentation, levels of acute and chronic sedimentation are very high at the Mainland Reef. In contrast, the East Lewis Reef (EL) has the opposite aspect and is located in a bay on the leeward side of East Lewis Island. Much of its coral growth occurs on top of thick (1m) stands of dead or partially dead Pavona decussata that elevate the corals approximately 1m above a sandy bottom (5-7 m depth). The East Lewis Reef is sheltered from the winds and waves resulting from storms and cyclones in summer and is buffered from the weaker winds that blow off the mainland in winter. There is little sediment accumulation at this reef because of its rates of sedimentation are comparatively low. -Sampling regime- In a random sample of over 50 free-living polyps from around the study area at each reef (see large thumbnail), ranging in diameter from 3cm to 21cm (mean = 10cm), all were identified taxonomically as F. fungites. Additionally, electrophoretic analysis of a random ...
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