Fauna of New Guinea

The fauna of New Guinea comprises a large number of species of mammals, reptiles, birds, fish, invertebrates and amphibians.

As the world's largest and highest tropical island, New Guinea occupies less than 0.5% of world's land surface, yet supports a high percentage of global biodiversity. Approximately 4,624 vertebrate species inhabit the island of New Guinea and its surrounding waters, which constitutes about 8% of the recognized world vertebrates. This ranges from an estimated 4% of the world's lizards and mammals, to about 10% of the world's fish species.^[1]

The numbers of global and New Guinea invertebrate species are poorly known, and thus an accurate comparison is difficult. Butterflies are the best known invertebrate group, and are represented in New Guinea by about 735 species, which is about 4.2% of the world total of 17,500 species.^[1]

Nevertheless, despite the rich biodiversity, New Guinea's megafauna diversity is quite low since the Pleistocene extinction event, especially when it comes to apex predators. For example, there are only three terrestrial animals at the top of the food chain. Of the three, two are obligate carnivores such as the crocodile monitor and the New Guinea singing dog, whilst one, the cassowary, is actually a frugivore but predatory opportunistically and seasonally.^[2][3] In the air, the only endemic apex predator is the New Guinea harpy eagle, whilst in the riverine systems, there are only two, the saltwater crocodile and the smaller New Guinea crocodile.