North Island Brown Kiwi
The kiwi is a special and quirky bird: it is flightless, has spikey hair-like feathers, digs burrows with its strong legs, and is active mostly at night. Kiwi are unique to New Zealand and are found nowhere else in the world! Kiwi spend their entire life on the ground foraging around the forest floor; they have plump rounded bodies with no tails and adults can weigh around 2kg or more. The kiwi’s strong sense of smell and its long bill mean it can easily hunt out worms and other invertebrates hiding in the ground. The kiwi is the national icon of New Zealand Aotearoa and New Zealanders are often called ‘kiwis’ both at home and overseas.
Brown kiwi (Apteryx mantelli)
New Zealand is home to five different kiwi species: brown kiwi, rowi, tokoeka, great spotted, and little spotted. The kiwi we have here in Whakatāne are brown kiwi (Apteryx mantelli). All brown kiwi live on the North Island of New Zealand. While the brown kiwi is one of the most abundant kiwi species (Kiwis for Kiwi estimates the brown kiwi population at 24,550 in 2015), kiwi numbers in unmanaged areas are declining quickly. The Department of Conservation classifies the brown kiwi as ‘threatened: nationally vulnerable’ and the IUCN Red List lists brown kiwi as ‘vulnerable.’
Interesting brown kiwi info:
- They can live up to 50 years.
- The females lay the eggs but it is the males who sit on (or incubate) the eggs in the burrow.
- The female kiwi lays eggs that are about one-fifth of her own body weight! She can lay up to 100 eggs in her lifetime.
- They sleep during the day in dark places such as burrows, under vegetation like ponga (tree fern) fronds, or even under tree roots.
- Chicks come out of the egg as miniature adults and are not fed by their parents.
- Juvenile kiwi will wander alone through the bush until they find a mate and territory. This can sometimes take years.
Where do they live?
Kiwi live in indigenous forest, shrub lands, exotic forests and rough farmlands. Kiwi are territorial, with each territory ‘owned’ by a male kiwi and his female mate; they are feisty and often aggressive toward unwanted intruders, fighting off invaders with their claws and growling. Male kiwi will call out at the edges of their territories to make sure other males know to stay away.
In Whakatāne kiwi live in all three of the reserves next to our urban area: Ōhope Scenic Reserve, Kohi Point Scenic Reserve, and Mokorua Scenic Reserve. There is also a small population on Moutohorā (Whale Island) just off shore from town. Indeed, Whakatāne kiwi live so close to our town that they are occasionally spotted in people’s backyards or crossing our walking tracks in the early hours of the morning.
What do they eat?
Kiwi are omnivorous, meaning they eat a variety of plants and animals. Using its long bill, a kiwi will probe the ground for insects, worms, spiders, grubs and berries. Kiwi have an exceptional sense of smell and can detect their food through leaf litter, rotting logs and soft soil. As kiwi are nocturnal (active during the night), they hunt in the dark and often travel one to two kilometres every night in search of food.
Kiwi tend to mate for life, which may be up to 40 years. The female is 20 to 30 percent bigger than the male and will lay eggs for the male to incubate. The male is also tasked with preparing the nesting burrow. He will use his strong legs and claws to dig a hole in the earth of a bank or slope, and then line it with a selection of soft leaves, grass and moss, finishing it off with a final layer of feathers. In an attempt to camouflage the burrow from intruders and provide insulation against the cold, kiwi will often build leaves and sticks across the entrance to the nest.