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Merremia peltata, disturbance ecology, tropical cyclones and Samoa. The biology and ecology of Merremia peltata are not well understood. While some regard the species as an exotic invader of Pacific Island ecosystems (Meyer. 2000). others identify the plant as a native species likely to be harmful to native ecosystems (Whistler, 1995a. 2002) or as either native or ancient Polynesian introduction behaving invasively (Space and Flynn.(2002). In Samoa, this species occurs up to an elevation of around 300 meters (Whistler 1995a). and thus only affects lowland ecosystems. This species increases its distribution and abundance in two ways, either vegetatively. by sprawling into neighboring areas and rooting from its nodes or by seeds, although early research in the Solomons observed a low seed viability rate, and creeping may thus be its primary means of reproduction (Bacon. 1982). M. peltata has apparently been in the Pacific for hundreds of years (Whistler, pers. com.) but has only become invasive in the years following tropical cyclones Ofa (1990) and Val (1991) according to comments from local government officials. Disturbance thus appears to be an ecological contributing factor to this invasion.

Six archaeological sites up to 1000years old on Aitutaki, Cook Islands, have yielded bones of 15speciesof birds, five of which no longer occur ontheisland: Pterodromarostrata(Tahiti Petrel);Sula sula(Red-footedBooby); Dendrocygna,undescribedsp.(alarge,extinctwhistlingduck); Porzanatabuensis (Sooty Crake); and Vini kuhlii (Rimatara Lorikeet). Of these, only S. sula and P. tabuensis survive anywhere in the CookIslands today.The nearest record of anyspecies ofDendrocygnaisinFiji.Asidefrom theaquaticspeciesEgrettasacra (Pacific Reef-Heron) and Anas superciliosa (Gray Duck), the only native, resident land bird on Aitutakitoday isthe SocietyIslands Lorikeet(Viniperuviana), which may have been introduced from Tahiti. Residents ofAitutaki note that Ducula pacifica (Pacific Pigeon) and Ptilinopus rarotongensis (Cook Islands Fruit-Dove)also occurredthere until the 1940sor 1950s.There isno indigenous forest on Aitutaki today. The bones from Aitutaki also include the island's first record of the fruit batPteropus tonganus. Limestone caveson the island of Atiu yieldedthe undated bones of sixspeciesof birds, three of which no longer exist there or anywhere elsein the Cook Islands: Gallicolumba erythroptera (Society Islands Ground-Dove),Ducula aurorae (SocietyIslands Pigeon),and Vinikuhlii. Each of these specieshas been recovered from prehistoric sites on Mangaia as well. The limestone terrain of Atiu is mostly covered with native forest that supports populations of Ducula pacifica, Ptilinopus rarotongensis, Collocalia sawtelli(Atiu Swiftlet), and Halcyon tuta (Chattering Kingfisher). The survival of these land birds depends upon protection of Atiu's forests.