Birds, being capable of flight, comprise most of the vertebrate fauna on remote Pacific islands. The sea birds are naturally quite similar throughout the tropical Pacific and are most numerous on uninhabited islands where they resort for breeding purposes. Among the common sea birds are albatrosses, boobies, terns, petrels, gulls, shearwaters, and cormorants. The migratory birds include ducks, golden plover, and the curlew. Land birds are very abundant on the high islands of the western Pacific, where they include cockatoos, parrots, birds of paradise, pigeons, swallows, kingfishers, hornbills, honey suckers, etc. In the central Pacific endemic species of land birds are fairly common. In both Australia and New Zealand are found species of flightless land birds, for example, the moa and kiwi of New Zealand and the emu and cassowary of Australia, a species of the cassowary also occurring in New Guinea. Originally flightless rails of different species lived on Laysan Island and Wake Island; the Laysan species was introduced on Midway and survives there but is probably extinct in its native haunts.
The only native mammals outside of New Guinea and Australia are bats and rats. Some land reptiles, mostly small lizards, are native to certain Oceanic islands, and a very few amphibians are found. Large monitor lizards live on Komodo and a few other islands of the eastern Indies, and a good-sized species is found in New Guinea. Snakes are common in New Guinea and include a few poisonous species. The big island also has crocodiles and the manatee, a harmless aquatic mammal. Harmless snakes live in Samoa and Fiji, and snakes become more numerous in the Solomons and the Bismarck Archipelago.
Cattle, pigs, goats, deer, rabbits, mongooses, and rats have been introduced by man on some islands, and sometimes the newly introduced animals have become pests that have destroyed much of the native plant and bird life and may injure gardens and crops.