Threats

Today the birds are under siege. By 1998, the population had plummeted to fewer than 100,000 birds.  By 2008 that figure had fallen even further – to about 70,000.

Over the past 15-20 years, where kiwi are being managed – in Department of Conservation kiwi sanctuaries, in community-led projects (many of them sponsored by BNZ Save the Kiwi) and on offshore island sanctuaries – the news is heartening and populations are stable or increasing.

But outside these managed areas, kiwi populations are predicted to continue to decline because management is only happening in small pockets of where they live.

Tragic statistics

A tiny proportion of kiwi eggs produce a kiwi adult.

• About 50% of all kiwi eggs fail to even hatch – sometimes because of natural bacteria, sometimes because the adult bird is disturbed by predators.
• Of eggs that do hatch, about 90% of chicks are dead within 6 months.
• 70% of these are killed by stoats or cats, and about 20% die of natural causes or at the jaws and claws of other predators.
• Only 10% of kiwi chicks make it to six months.
• Fewer than 5% read adulthood.

Official status

According to the Department of Conservation, all 11 kiwi taxa are in trouble to some degree. The Department’s threat classification for each taxa is shown in Table 1.

Table 1: Threat classification of the 11 kiwi taxa.

Little spotted kiwi are on the road recovery.

Rowi have increased their population, mainly due to BNZ Operation Nest Egg™.

The decline of both Haast tokoeka and Coromandel brown kiwi has been halted thanks to extensive predator control and, for Haast tokoeka, BNZ Operation Nest Egg™.

The other three taxa of brown kiwi are still in decline. Although some actively managed populations are flourishing, most birds live in sites with little or no management.

The other three taxa of tokoeka have no direct management and are assumed to be gradually declining, especially in lowland and drier areas.  

Great spotted kiwi receive little active management, and although some populations in upland wet areas appear to be stable, those in lowland and drier areas are assumed to be declining gradually.

The source of the threat

Kiwi face threats from three main directions – predators, lost habitat and people.

It can become a downward spiral.  As kiwi populations decline and become fragmented, sex ratios skew and the effective breeding population further declines.   And so it goes…