Origin of the New Hebridean avifauna

Abstract

As background, the physical environment and avifauna of the New Hebrides in the Southwest Pacific are briefly described. The major routes by which birds invaded the New Hebrides are from Australia (possibly via New Caledonia) and from New Guinea via the Bismarcks and Solomons, with a minor route from Fiji. From the New Hebrides, birds in turn colonized New Caledonia, Fiji and Polynesia, the Solomons in a strikingly stratified pattern, the Bismarcks scarcely and New Guinea and Australia not at all. The concept of faunal dominance is supported by the asymmetry of these fluxes of species: the ratio of species exchanged between two archipelagos deviates further from 1.0 than does the ratio of the archipelagos' areas. Species that colonize archipelagos 'upstream' towards the source of colonization often become restricted to small or remote islands, poor in species, thereby generating many of the supertramps of the Pacific. Appendices summarize sources of information about New Hebridean birds and, for each species, its island-by-island distribution within the New Hebrides, extralimital range, closest relatives and references to taxonomic studies.