The only native mammals are the flying fox, the bat, and the rat. The pig was unknown to the indigenous people prior to European contact. The deer that inhabit the savannas of Grande Terre are descended from two pairs introduced in 1862.
Some of the butterflies possess a rare beauty. Eighty-eight species of birds are found in New Caledonia, 18 of them endemic. Only a few hundred specimens of the Ouvéa parakeet still exist. The purple swamp hen with its red beak and blue body is often seen running around west coast campgrounds.
The national bird is the flightless cagou (Rhynochetos jubatus), or kagu, about the size of a small rooster. This bird has lovely soft gray plumage, contrasted by striped brown-and-white wings. The cagou's crest rises when the bird is angered, and its cry is like the bark of a dog. It eats insects, worms, and snails. Since it hatches only one egg a year and is slow on the ground, the cagou is threatened with extinction: Dogs often outrun and kill it. Fewer than 2,000 survive in Rivière Bleue Provincial Park at the west end of Yaté Lake and elsewhere.
The extreme richness of life on the reefs compensates for the lack of variety on land. New Caledonia's 1,600 km of barrier reefs are home to 350 species of coral, 1,500 species of fish, and 20,000 species of invertebrates. The territory's protected lagoons total 23,000 square km, with an average depth of 20 meters—the largest lagoon complex in the world.