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Island biotas often have lower species diversity and less intense competition has been hypothesized as a result. This should result in lower habitat specificity compared with mainland habitats due to larger realized niches. We investigate microhabitat associations of canopy trees with regard to differences in topography on an oceanic island (Viti Levu, Fiji) using twenty 10 × 60-m plots. We find high tree-species diversity (112 species with dbh ≥ 10 cm in a total of 1.08 ha) and high endemism (c. 60%), compared with other islands in Western Polynesia. Our sample plots aggregate into three distinct groups that are mostly defined by micro-topography: (1) ridges and steep slopes (well-drained sites), (2) moderate slopes and ridge flats (moderate drainage), and (3) flats (poor drainage). Associations with microhabitat are found for more than 50% of the 41 most common species but only one species is apparently restricted to a single habitat. These findings are similar to other rain forests and demonstrate considerable niche differentiation among island rain-forest tree species. [ABSTRACT FROM PUBLISHER]

The poorly studied bat fauna of the Fiji Islands is of notable conservation importance because it includes one endemic species, several near endemics, and the best global populations of several threatened species. In addition, some of the species play a keystone role as pollinators and seed dispersers in valuable forest ecosystems. We visited 30 islands of the archipelago to survey bats and assess their conservation status and the potential threats to their continued existence. The Vulnerable Notopteris macdonaldi occurs on the three main islands but may only have nurseries on one of them. The Critically Endangered, endemic Mirimiri acrodonta appears to be restricted to a small montane area on a single island. Pteropus tonganus is consumed throughout rural Fiji but remains common and is not currently threatened by the harvest. The Near Threatened Pteropus samoensis is locally common on the largest islands but threatened on some smaller islands. The Endangered Chaerephon bregullae exists only on two islands and appears to concentrate in a single large colony to nurse young. The Endangered Emballonura semicaudata has declined dramatically in Fiji, as across most of its range, although a few substantial populations remain on some small islands. Factors threatening these species are variable but include small ranges, concentration in a reduced number of colonies, deforestation, over-harvesting, and introduced predators. We propose conservation measures and indicate a number of priority sites. [ABSTRACT FROM AUTHOR]