The kiwi (scientific name Apteryx), which is roughly the size of a chicken, is a tiny, flightless, and practically wingless bird that can only be seen in New Zealand. kiwi, Emu, ostrich, rhea, are categorized as ratites (bird with smooth breastbone). Many birds have a keel (ridge along the breastbone) on their sternum (breastbone) where their flight muscles attach, but ratites don’t require one because they don’t fly. Over many decades, scientists believed that the kiwi was closely related to the moa,
Alt: the image of a kiwi bird
Description: Black and white illustration of kiwi
another New Zealand ratite. But, the latest genetic research has revealed that the this bird is much more genetically connected to the extinct elephant bird of Madagascar
Whatever might be the case! It has large feathers, and its wings are roughly an inch long, but they are useless and buried behind the features. lack a tail, but they do have incredibly powerful, muscular legs that account for around one-third of the bird’s total body mass and are employed for running (12 miles per hour) and fighting. It can pad gently throughout the jungle on four toes to every large foot (usually ratite have two or three toes) in quest of food. They are devoid of the uropygial gland(green gland). Their bill (beak) is extremely lengthy, supple, and touchable. Barbules and aftershafts are absent from their features.
It possesses several bodily components that seem similar to a mammal, such as denser and tougher skin, bones packed with marrow, a cat-like claw on the tip of its wings, similar to bats, but it is inactive and has a lower body temperature (38-degree Celsius). Instead of creating a nest, this bird digs tunnels. It has adapted features that serve as whiskers (comparable to moustache) on its face and at the base of its beak, and its features are long, loose, and hair-like.
Habitat And Diet
It’s inhabits New Zealand’s wooded areas, which are sometimes quite steep and damp, and are ringed by bushes and plants found nowhere else on the planet. Even though it is unable to fly, It seeks refuge in burrows dug into the ground in marshy forest or grassland habitats to rest or avoid predators. Using powerful toes and claws, the bird digs many burrows around its domain. Burrows are dug earlier in the season so that the opening becomes lush and dense providing excellent concealment (covering) by the time the mother is prepared to deliver eggs.
Most of these birds sleep at night, but because they are rarely observed during the day, it was long assumed that kiwis were an exception and are nocturnal (active at night). However, recently scientists have observed them throughout the day in New Zealand’s South Island. Even yet, it prefers to sleep in deep subterranean tunnels or empty logs, during the day and when night falls, it slowly shoots its own bill (beak) outside to sense the air. If the light goes green, the bird comes out carefully to begin its nightly habit of consuming worms and other invertebrates.
Why Kiwis Still At-Risk After So Many Conservation Attempts
Alt: Photo of dead kiwi
Description: Photo of kiwis killed by dogs and cars passed by
It grew to learn to share their home with another flightless bird, the weka, which consumes their eggs, forcing them to become clever in concealing burrows. However, as kiwis toss dirt behind them while building the entrance, their sleeping burrow has a visible dirt arrow leading directly to it. Kiwis lack sufficient anti-mammal predatory mechanisms since they did not evolve with mammal predators; their chicks are vulnerable to foreign predators such as cats and dogs, stoats, weasels, ferrets, and rats. unfortunately, have a 95 per cent chick mortality rate.
Some Unique Features That Are Found
It is the only bird in the world which has nostrils on its beak. It feeds on grubs, worms, beetles, berries, and seeds, using only its keen sense of smell and sensory pads at the tip of its beak to grab its meal. It can sneeze away dirt that gets stuck in his nose. It can also kick apart decaying logs in search of bugs to eat using its strong, muscular feet.
It can be observed snuffling (breathing noisily) around their area all day, and if they are disturbed, they flee and then stick their beak in the air, smelling to check if it is safe to go back. Their ears are big, allowing them to hear quite well. They have been observed, like humans, bending their heads toward a sound to hear more precisely.
These are fiercely possessive of its area since it does not want other kiwis to take all of the delicious food and burrows that it has worked so hard to create. As a result, the kiwi guards its territory every time, leaving stinky droplets to mark borders and keep other kiwis at bay—an unusual habit for a bird. Kiwis may yell loudly to keep track of each other in the night, a half-scream or a half-whistle can also help to warn strangers to stay away. The birds’ name comes from its call, which sounds like “kee-wee, kee-wee”. When enraged, the kiwi may also grunt, snort, and hiss.
Family And Personal Life
It communicates with one another and their young ones via soft moans and snuffles, and males purr (vibrating sound expressing contentment) during mating. Pairs do fight, and if the stronger female isn’t in the mood for his company, she will kick the male off. If another kiwi intrudes on a pair’s territory, kicking combat is inevitable, and kiwis have already been known to fight to the bitter end, but this is uncommon.
Adult females and male kiwis normally couple for life, but if a more appealing male passes by, the female may pick a new male. To attract a female, the male does not have lovely songs or elegant plumage. Instead, he grunts and chases one around continually. If she isn’t interested, the female may flee or attempt to frighten him away.
Alt: kiwi and its offspring
Description: Little spotted male kiwi with its 4 weeks old offspring
Late winter to early summer is the breeding season. Nests can be found in subterranean tunnels created by males. Every year, the female kiwi lays six eggs white, off-white, or pale green in colour, eggs are smooth. They’re also big in proportion to the mother: one egg may weigh up to 20% of the mother’s weight, which is equivalent to a 60 kg woman giving birth to a 12 kg child.
Evolution For The Creation Of A Huge Egg
Owing to an ample food resource that provided sufficient raw material for reproductive performance, the kiwi’s loss of flight, which removed the egg’s weight constraint, and the absence of predatory stress on the bird, which had no indigenous New Zealand predators in the past. Because of the big egg, the incubation time is longer. As the size of ancient kiwis dropped, the egg remained the same size, allowing for a highly developed chick that required less parental care.
After the egg is deposited, the male acquires parental responsibility. He sits on the egg for about 75 to 85 days for incubation and maintaining the nest, but if the female arrives to lay another egg, the male must remain on the clutch (group of eggs) for even longer. Kiwi parents do not hatch their eggs, unlike most other bird parents.
The chick only needs to kick its way out of the shell because it lacks an egg tooth. It emerges from the nest with shaggy adult feathers and the appearance of a smaller version of its parents. The infant is not fed by the parents and instead feeds itself from a vast yolk store in its belly. For the first few days, the chick remains in the nest and gains strength. The juvenile kiwi then emerges from the burrow, escorted by his father, to begin his hunt for food.
These birds was always believed to mate for life, but it has since been discovered that the “divorce rate” among kiwis is rather high, with birds changing partners after a couple of years in places where kiwis are widespread.
There are only five known species and many subspecies namely
- Great spotted roroa (Scientific name Apteryx haastii)
- Little spotted kiwi (Scientific name Apteryx owenii)
- Okarito kiwi or rowi or Okarito brown kiwi (Scientific name Apteryx rowi)
- Southern brown kiwi or tokoeka or common kiwi (Scientific name Apteryx australis)
- North Island brown kiwi (Scientific name Apteryx mantelli)
Some Unusual Facts To Know
- The offspring are ready to go as soon as they are hatched.
- Kiwi lacks egg tooth.
- It has very poor eyesight some are even found blind but still, they were healthy that’s the reason they depend on other senses
- Kiwis are omnivores.
- They do have wins but can’t fly.
- They shed their feathers for the whole year.
- They have one of the largest egg-to-body weight ratios.
- Only 5% of kiwi hatched in the forest could survive.
- They are long-living birds depending on the species they can live for between 25-50 years. But the lifespan can be short in captivity.
- Once little spotted kiwi went to 1200 from just 5.
- They don’t have hollow bones, rather they have marrow just like humans or we can say mammals.
- They are named after the sound they make “kee-wee”.
- It is one of the birds with females having a pair (both left and right) of functioning ovaries.
- The kiwis have a very good sense of smell, rare in birds.
- It is the only bird in the world with nostrils at the tip of the beak and if the nostrils become filled with dirt, then the kiwi can deliberately sneeze to remove it.
- They evolved around 30 million years ago making them one of the oldest types of living creatures.
- They have a much lower body temperature than any known bird.
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Authored by Sumiti goel