13 Kiwi Facts on New Zealand's Iconic Birds
Kiwis are flightless birds native to New Zealand. From their huge eggs to their reliance on smell rather than sight, kiwis look more like mammals than birds. Beyond their unique adaptations, they are also iconic for renaming a fruit! Is your interest piqued? Read on for more Kiwi facts to learn more.
To learn more about avians in general, save our bird facts.
Summary: Essential Kiwi Facts
| Kiwi Profile | |
|---|---|
| Scientific Name: | Apteryx |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Struthioniformes |
| Family: | Apterygidae |
| Genus: | Apteryx |
| Species: | 5 known species (Great Spotted Kiwi/Roroa, Little Spotted Kiwi, Okarito Kiwi/Rowi, Southern Brown Kiwi/Tokoeka, North Island Brown Kiwi) |
| Physical Characteristics | |
| Size: | 14-25 inches depending on the species |
| Weight: | 1.3-3.3 kg depending on the species |
| Distinctive Characteristics: | Flightless, long beak, brownish-gray feathers, female larger than male |
| Habitat and Range | |
| Location: | New Zealand |
| Habitat: | Forests, scrublands, and grasslands |
| Range: | Specific to species, Great Spotted Kiwi found in the South Island, Little Spotted Kiwi and Okarito Kiwi in restricted areas of South Island, Southern Brown Kiwi in Stewart Island and Fiordland, North Island Brown Kiwi in North Island |
| Conservation Status | |
| Status: | Ranges from Vulnerable to Critically Endangered depending on species |
| Threats: | Habitat Destruction, Introduced Predators (Stoats, Dogs, Rats) |
| Initiatives: | Operation Nest Egg, Kiwis for Kiwi, governmental predator control, habitat conservation |
Kiwi Q&A
These Are Some of the Most Common Questions People Ask About Kiwis with Answers:
- Can Kiwis fly? - No, Kiwis are flightless birds.
- How do Kiwis reproduce? - Kiwis are monogamous, and the female lays one large egg which is incubated by the male.
- What do Kiwis eat? - They primarily eat invertebrates, but also consume fruits, leaves, and other plant material.
- How long do Kiwis live? - In the wild, Kiwis can live to upto 50 years.
- Are Kiwis nocturnal? - Yes, Kiwis are active mostly at night and tend to sleep during day.
- Why are Kiwis important to New Zealand? - It's New Zealand's national symbol and plays a crucial role in the ecosystem by dispersing seeds and controlling insects.
- Why are Kiwis called "Kiwi"? - They are named after the call sound they produce, which sounds like "kee-wee".
- How does a Kiwi's size compare to its egg? - Kiwis lay huge eggs for their body size, sometimes up to 20% of the female's body weight.
13 Facts About Kiwis In Detail
1. There are five kiwi species.
Kiwis belong to the ratite group, which includes emus, ostriches, and the now-extinct moa. Their closest living relative is the elephant bird from Madagascar. There are five different kiwi species endemic to New Zealand.
The North Island Brown Kiwi (Apteryx mantelli), known for its brown plumage, is one of the most widespread kiwi species. On the other hand, the Rowi or Okarito Kiwi (Apteryx rowi) is critically endangered and inhabits a limited area in the north of the South Island.
The Tokoeka (Apteryx australis), comprising several subspecies, adapts to various habitats nationwide, showcasing the kiwi's versatility. The Great Spotted Kiwi (Apteryx haastii) thrives at higher altitudes on the North Island. Lastly, the Little Spotted Kiwi (Apteryx owenii), the smallest species, has been reintroduced to predator-free islands to secure its survival.
Related: World's smallest birds.
2. The largest kiwi is the Great Spotted Kiwi.
The Great Spotted Kiwi is the largest of all the kiwi species. They can weigh up to 7.3 pounds and measure around 20 inches tall. These impressive birds are found on the North side of the South Island in New Zealand and inhabit higher altitudes than other kiwi species.
Related: If you want to know the largest bird, which happens also be flightless, head to our ostrich facts.
3. Most kiwi species are nocturnal.
These flightless birds are nocturnals like owls. Kiwis have excellent smell and touch that help them sniff the food and detect potential dangers1. Their vibrissae also allow them to sense vibrations and movements. (More on this in another Kiwi fact below) These omnivores use their long beaks to probe the ground for invertebrates, seeds, berries, and grubs, utilizing the forest floor as their pantry at night.
Related read: More Bird with Big Beaks.
4. They cannot fly.
The wings of these birds are not fit for flying, setting them apart from most other birds. This behavior may stem from the previous absence of land mammal predators in their habitat. Furthermore, unlike typical birds with hollow bones, the kiwi's bones are solid and filled with marrow, resembling those of mammals.
The Kiwi fact below discusses the birds ' mammalian features even if they are technically part of the Aves class.
5. Kiwis are also called honorary mammals.
Kiwis are not your typical birds. Their unique adaptations are more mammal-like, which helps them receive the name "honorary mammals." One of the kiwis' most notable mammal-like features is their highly developed sense of smell. Unlike most birds that rely on sight, the kiwi is the only bird with large nostrils at the tip of their long, slender bills.
Another mammalian trait of kiwis is the presence of whisker-like feathers around their face. These specialized feathers, known as vibrissae, are sensitive to touch and help the birds navigate in low-light conditions.
Similar to how mammals use their whiskers to sense their surroundings, kiwis utilize their vibrissae to feel their way through their forest habitats at night. Additionally, the kiwi lacks a tail but has a small tailbone. It also has powerful legs and claws adapted for digging and defense.
6. Kiwi birds are monogamous.
Kiwis show loyalty in their lifelong partnerships5. Unlike many birds, they stick together, cooperating and caring for their territory. After the female kiwi lays her eggs, she forages for food while the male takes over incubation duties. This devoted fatherhood can last up to 80 days.
Kiwis have unique courtship calls that strengthen their bond and help them find each other in the dark forest. During the breeding season, males can call out up to 20 times a night to woo their partners. Now that's perseverance!
Related: You can visit our penguin facts to read more about loyal birds.
7. Brown Kiwi has two ovaries.
The brown kiwi is a unique bird with a fascinating reproductive feature. Unlike most birds that typically have only one ovary, the North Island female brown kiwi is unique because it has both left and right ovaries.
8. Kiwis lay the largest egg.
The Southern Brown Kiwi defies expectations with its large kiwi egg compared to its small size. These eggs can weigh up to 25% of the mother's body weight, giving the kiwi chick a strong start in life. In comparison, an ostrich's egg makes up only 2%.
The secret lies in the enormous yolk that fills the egg with nutrients. The female kiwi consumes three times her usual food to create this nutrient-rich yolk, fasting just before laying the egg.
The egg-laying process is an endurance test, taking up to three hours. The kiwi chick emerges fully feathered and independent, thanks to the nourishing yolk. The kiwi's large egg is not just an eccentricity; it's a clever strategy to ensure that kiwi chicks survive3.
The following kiwi facts explain the popularity of these flightless birds.
9. Kiwis gave their name to New Zealanders and a fruit.
New Zealand cartoonists first used the kiwi bird to symbolize the nation in the early 1900s. This practice extended to World War I when the troops got the kiwi nickname. Eventually, all New Zealanders took up this label with pride.
On the other hand, Chinese gooseberry seeds found their way to a humble farmer in New Zealand, where they successfully grew fruits by 1910. In 1959, the fruit's exporter, Turners & Growers, rebranded it as 'kiwifruit' for successful marketing in the U.S., drawing inspiration from native birds' brown and fuzzy appearance. By the 1970s, the name kiwifruit, or simply kiwi, had replaced Chinese gooseberry in global trade.
10. Kiwis are New Zealand's flagship species.
The kiwi bird is not only a native of New Zealand but also a cherished national symbol. It is found nowhere else in the world, making it unique and treasured. Kiwis appear on the country's one-dollar coin and essential symbols like the Coat of Arms and Defence Force emblem.
The native Māori people had a sacred relationship with Kiwis. They believed the gods protected the birds and used their feathers for ceremonial kahu kiwi cloaks. While they no longer hunt kiwis, they still collect feathers from those who have passed on.
11. These flightless birds live long lives.
With lifespans reaching up to 50 years and beyond, kiwis defy the norms of bird species. They begin breeding later in life, usually between three and five, and lay only one egg per season. Their extended lifespan supports this leisurely approach to reproduction.
Despite their long lives, they face numerous threats, which we discuss next.
12. Only 5% of Kiwi chicks survive in the wild.
The survival rate of Kiwi chicks in the wild is a concerning statistic that highlights the challenges these iconic birds face in their natural environment. According to studies and research, only around 5% of Kiwi chicks reach adulthood successfully.
Several factors contribute to this low survival rate. One of the primary threats is predation by introduced mammalian predators, such as rats and cats. The absence of natural defenses, like flight, leaves the young Kiwis particularly vulnerable to these predators. By removing the eggs from the wild and rearing them in safe, controlled spaces, the survival of kiwi eggs can increase to 60%.4
13. They are near extinction.
The kiwi bird is in a challenging situation. According to the IUCN Red List, four out of five kiwi species have a vulnerable status. And as of this writing, two of those species have decreasing population trends.
The biggest threat to kiwis is introduced predators2. Stoats, dogs, and cats are making things worse for both adults and chicks. Stoats, in particular, are a significant threat to kiwi chicks. They cause nearly half of the wild kiwi and kiwi chick deaths. Because of this and their slow breeding, bringing Kiwi numbers back up is difficult.
But hope is not lost. The New Zealand government has launched programs to boost the kiwi population within their natural habitat. Other community initiatives, like Project Kiwi, are also making a difference. These efforts have made significant strides in protecting kiwi habitats and controlling predators. They also ensure the successful rearing of kiwi chicks before their release into the wild.
Whether you're a New Zealander or not, share these kiwi facts and spread the love for these unique flightless birds.
Related: To further explore the animal kingdom, check out some of the other animals that start with K.
| 1 | Cunningham, S. J., Castro, I., & Alley, M. R. (2007). A new prey-detection mechanism for kiwi (Apteryx spp.) suggests convergent evolution between paleognathous and neognathous birds. Journal of Anatomy, 211(4), 493-502. |
| 2 | Robertson, H., et al. (2021). Conservation status of birds in Aotearoa New Zealand, 2021. New Zealand Threat Classification Series 36. New Zealand Department of Conservation. |
| 3 | Calder, W. A. (1979). The Kiwi and Egg Design: Evolution as a Package Deal. BioScience, 29(8), 461–467. |
| 4 | Germano, J., et al. (2018). Kiwi (Apteryx spp.) recovery plan 2018–2028. Threatened Species Recovery Plan 64. New Zealand Department of Conservation. |
| 5 | Reid, B., & Williams, G. R. (1975). The Kiwi. In Monographiae biologicae (pp. 301–330). |
Chinny Verana is a degree-qualified marine biologist and researcher passionate about nature and conservation. Her expertise allows her to deeply understand the intricate relationships between marine life and their habitats.
Her unwavering love for the environment fuels her mission to create valuable content for TRVST, ensuring that readers are enlightened about the importance of biodiversity, sustainability, and conservation efforts.
Fact Checked By:
Isabela Sedano, BEng.
