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La liste préventive des espèces exotiques envahissantes de Wallis et Futuna a été créée en 2024 par une révision de la règlementation, à la suite d'une prestation d’une biologiste, et de la consultation d’associations et de services du territoire. Elle répertorie 123 espèces absentes du territoire mais présentes dans la région et dont Wallis et Futuna entend se préserver. Le document compile des fiches techniques de reconnaissance et de gestion des 123 espèces figurant sur la liste préventive, relatives aux milieux terrestres, humides et de rivières et marins. Le document détaille également les 6 étapes du plan d'intervention rapide élaboré pour répondre aux introductions d'espèces exotiques envahissantes à Wallis et Futuna : (i) réceptionner le signalement, et collecter les informations; (ii) confirmer l'identification de l'espèce; (iii) améliorer la connaissance sur la répartition de l'espèce; (iv) évaluer la situation et choisir l'option de gestion; (v) élaborer et mettre en place un plan d'intervention et (vi) veiller.

The lagoon of Tarawa harbors the richest benthos documented for any Pacific atoll. The biota is strongly influenced by its setting in the equatorial upwelling zone and the unusual geomorphology of the atoll, with a submerged western rim, but largely closed and islet-strewn eastern and southern sides. As the metropolitan center of the Republic of Kiribati, Tarawa also has the largest human population of any Pacific atoll. These three attributes impose a strong influence on all aspects of the lagoon. The high regional productivity supports unusually high population densities of heterotrophic mollusks and irregular echinoids for an "open" atoll. The dense human population on the atoll relics largely on marine resources for its protein needs. The lagoonal sand flat harbors dense and diverse mollusk communities, particularly in seagrass beds. These communities support an intensive subsistence fishery with an annual harvest of ca. 1,000 tons in South Tarawa. Much of the available biomass of the two preferred species, the blood cockle Anadara uropigimelana (te bun) and the small conch Strombus luhuanus (te nouo), is taken. Both the seagrass and shellfish beds appear to have expanded considerably in the past 50 years, likely as a result of nutrient enrichment from the rapidly growing human population. Dense mollusk communities along the southeastern lagoon slope at 2-8 m depth support an intensive commercial fishery that harvests approximately 1,000 tons of Anadara per year, again representing much of the available production. Three species of irregular echinoids are conspicuously abundant on the floor of the eastern lagoon, with combined densities > 100 m-2 in the muddy facies of the inner lagoon. All aspects of the benthos follow a marked west-to-east and north-to-south zonation, reflecting the one-sided exchange of oceanic waters along the western atoll rim. While mollusk and echinoid biomass increases southeastward, coral diversity and cover decreases in that direction.

The purpose of the present study is to: 1/ list the presently known heterodont bivalve fauna of the Cook Islands, 2/ document the habitat specificity of the species involved in as much detail as possible, and 3/ investigate the correlation between a species' habitat specificity and its distribution among the various islands. While several studies have been done on the molluscan fauna of inner reef environments on Pacific islands (though bivalves are often neglected), there has been little work on the fauna of the outer reef slope. An important part of this study involved documenting the bivalve species living on this slope, and thus a large portion of my survey was carried out there.