Threats to kākā
Remains of an incubating North Island
kākā female, preyed on while on the nest
Kākā require large tracts of forest to survive. Habitat loss from forest clearance for agriculture and logging have had a devastating effect.
Browsing by introduced pests such as possums, deer and pigs has reduced the abundance of food. Possums also eat the same kind of food as kākā, most significantly, high energy food types such as endemic mistletoe and rātā.
Introduced wasps compete with kākā for the shimmering honeydew (excreted by scale insects) which forms on the barks of beech trees. Both the mistletoe and honeydew supply sugary food which is an important part of the bird's diet, and may be essential for it to breed in some beech forests.
Having evolved in the absence of mammalian predators, kākā have many characteristics that make them easy prey. Kākā nest deep in hollow trees, where there is no escape if they are cornered by predators such as stoats, rats and possums (which eat chicks and eggs). Nesting females are the most vulnerable to stoat attacks, resulting in a disproportionate male/female sex ratio.