New Zealand had no mammals until humans arrived with a number of feral pests. Kiwis have suffered heavy predation from these pests, which include Polynesian rats, Brushtail Possums, cats, stoats and ferrets. Young birds and eggs are particularly susceptible.
Since the 1990s, intensive conservation programs have worked to control pests and protect young birds by hatching wild-laid eggs in captivity. The small, isolated populations are still incredibly vulnerable to extinction.
Amazing Southern Brown Kiwis
There are four living species of kiwi, all of which are small, flightless birds found only in New Zealand. All share characteristics unique to kiwis, including an excellent sense of smell that they use to find food underground. Most birds have nostrils at the top of their bills near their eyes, but kiwis have nostrils at the tip. They stick their entire beak into the ground when hunting and use special valves to keep out dirt.
Kiwis have adapted to life without flight. They have bones filled with marrow, unlike flying birds, which have hollow bones to reduce weight. They have wings reduced to tiny stubs and no tail. Their feathers are fur-like since they are used for insulation rather than flight.
Southern Brown Kiwis live in a variety of habitats, including scrub, sand dunes, grasslands and forests. They are shy and agile birds that roam over their large home ranges at night in search of food. Males and females pair for life and maintain a strong bond by calling to one another. The female lays one enormous egg in a nesting burrow, and the male incubates it for 70–80 days. Young kiwis remain with their parents for 4–5 years.
This species is also known as the Tokoeka or Common Brown Kiwi, and it has four subspecies.