Threats to kiwi
Introduced mammalian predators, namely stoats, dogs, ferrets and cats, are the number one threat to kiwi. Other threats include habitat modification/loss and road strike. The restricted distribution and small size of some kiwi populations increases their vulnerability to inbreeding.
Northland brown kiwi mauled by a dog,
Taemaro Bay, Northland
Stoats are responsible for approximately half of kiwi chick deaths in many areas through New Zealand. Cats also to a lesser extent prey on kiwi chicks. The combined effect of these predators results in only 10% of kiwi chicks surviving to the age of six months. Young kiwi chicks are vulnerable to stoat predation until they reach about 1 - 1.2 kg in weight, at which time they can usually defend themselves.
Ferrets and dogs often kill adult kiwi. These predators can cause large and abrupt declines in populations. In particular, dogs find the strong distinctive scent of kiwi irresistible and easy to track, such that they can catch and kill kiwi in seconds.
Motor vehicle strike is a threat to all kiwi where roads cross through their habitat.