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Dugong dugon are the last extant species in the Family Dugongidae and are listed as Vulnerable to extinction by the IUCN Red List. The dugong population is believed to be in decline globally. Throughout its range, relic populations remain and are separated by large areas where populations have disappeared (Marsh & Lefebvre 1994). The degree of the decline of numbers or fragmentation of its range is not known for any country. For many countries the only information available is from incidental sightings, drownings and anecdotal information. The Pacific region supports the world's largest remaining population of dugongs (Marsh et al. 2002). Dugong occur in most of Melanesia, Papua New Guinea (PNG), the northeast and east coasts of Australia and as far east as Vanuatu.. The current status of dugongs is unknown throughout the region (Marsh et al. 2002) and information on dugong distribution and abundance is outdated or non-existent. It is likely that dugongs are widely distributed in small numbers in much of PNG. the Solomon Islands and Vanuatu and that larger numbers occur in the Papua New Guinea waters of Torres Strait. Marsh et al. (2002) states that their reliance on relatively shallow water seagrass beds for food, limits the ability of dugongs to travel between islands and continents that are separated by extensive areas of deep water. For this reason, many island populations become essentially isolated, making these populations especially vulnerable to extinction.

On the 21st of October, 1972, hurricane "Bebe" devas- tated a large part of Funafuti atoll, Ellice Islands. Among the most spectacular geomorphological alterations caused by the hurricane was a storm beach 19 km long, 4 m high and 37 m wide. The amount of coral debris washed up from the offshore coral reefs onto the reef flat was estimated at 2.8 x 10 tons of material (Baines, Beveridge and Maragos, 1974). The oceanside reef communities of the SE and E rim of the atoll had been totally destroyed, and those of the inner reefs of the lagoon side had been heavily damaged. Eight months after the storm a quantitative analysis of the resettlement and recruitment of coral species on 7 reef sections was carried out: the destruction of the biophysiographic zones could be described as increasing from the northern border and also to the W rim of the atoll. Near the centre at Fongafale the lagoon reef flat was covered by thick carpets of the brown alga Dictyota bartaysii, possibly brought about by eutrophication effects. The resettlement of the reef flat by corals began with the recolonization of branching corals as well as regeneration of the very few surviving massive corals: about 80% of the number of new colonies belong to Acropora (mainly A. humilis and A. hyaclnthus), and about 20% to Pocillopora eydouxi, Porltes lutea (?) and some Faviidae. The percentage of the area settled by the massive coral species is, however, greater than that settled by the branching species. Nevertheless, in the long-term, branching corals are expected to have a decisive influence on the future structural and biophysiographic zonation of the reef edge and reef flat, due to their more numerous young colonies, which are evenly scattered over the reef area, and due to their rapid growth rate. Consequently, an Acropora humilis - hyacinthus-community or an Acropora - Pocillopora eydouxi-assemblage can be predicted as the future biophysiographic zone.