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Reef fish assessments were undertaken in 17 Pacific islands to describe the status of finfish resources in 63 villages where fishing is mainly artisanal. Surveys were performed by recording the number and size of edible fish species and benthic composition. Fishing impact was described through six proxies representing level of catch, alternative incomes, degree of commercial catch and country economic development derived from a simultaneous socioeconomic assessment. The relative importance of broadly defined habitat (geographical location, island and reef type, substrate composition) and fishing impact in controlling the distribution of fish trophic groups, families and species was measured through multivariate analysis. The extreme faunistic diversity was shown by the large variation in fish density (difference of up to an order of magnitude) and fish biomass (displaying a 20‐fold difference across the region). Herbivores were dominant in the eastern part of the region, at what we classified as complex islands and at islands with small lagoon and at coastal reefs, while carnivores were dominant at oceanic islands and atolls and at outer reefs. Specific habitat associations were shown for Scaridae, Acanthuridae, Siganidae, Balistidae, Lethrinidae, Lutjanidae and Serranidae. Relative importance and size decrease of several fish families (Mullidae, Scaridae, Lutjanidae and Serranidae) were related to high fishing impact. Acanthuridae and Lethrinidae appeared to have a role as opportunistic groups in impacted sites. The relative impact from fishing and habitat on fishes accounted for, respectively, 20 and 30% of variance, demonstrating the effect of human impacts even at such large scale and taking into account only limited fishing impact variables.

Seamounts are habitats of considerable interest in terms of conservation and biodiversity, and in terms of fisheries for bentho-pelagic and pelagic species. Twenty datasets on seamounts and bathymetry from different sources and scales (from individual cruise to worldwide satellite data) have been gathered to compile a detailed list of seamount features for the Western and Central Pacific Ocean. None of the datasets is complete and errors exist in most of them. The Kitchingman and Lai (2004) dataset (KL04) from satellite altimetry data provided the baseline of this study because it covered the entire region of interest and includes depth information. All KL04 potential seamounts were cross-checked with other datasets to remove any atolls and islands incorrectly classified as seamounts, to add seamounts previously undetected by KL04, to update the overall database (geolocation, depth) and provide a 12-classes typology of the different types of underwater features. Of the 4,132 KL04 potential seamounts identified, 835 (20%) were actually atolls and islands and 268 were multiple identifications of the same feature (e.g. multiple peak seamounts) and 2 were removed, leaving 3,027 actual underwater features. Conversely, 541 seamounts documented in other datasets but not registered in KL04 were added. The screening of all the potential WCPO seamounts produces a list of 3,568 features with accurate position and information that should have many applications in fisheries and oceanography.

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