Living exclusively in New Zealand, the southern kiwifruit has lost its ability to fly during evolution. A morphological peculiarity that makes the species particularly vulnerable to its predators. Meet a small pear-shaped brown bird.
The southern kiwi, a runner
The southern kiwi (Apteryx australis) is a runner bird belonging to the order of the apterygiformes and to the family of the aptérygidae. Like other species of runner birds (ostrich, Australian emu, flightless cormorant, etc.), it is unfit for flight. His sternum does not have wishbone, a bone on which the pectoral muscles of birds usually hang. Its wings then atrophied with evolution, removing the Powerful sufficient muscle to fly. Taking its name from the Maori language, the southern kiwifruit is the national symbol from New Zealand. The animal measures 50 to 65 cm (the female being larger than the male) and weighs between 1.5 and 3.5 kg.
Nostrils at the end of the beak
The southern kiwifruit has very small wings that look like stumps of about 3 cm extended by thirteen flight feathers. Its pear-shaped body has plumage resembling a sort of hair brown to red which effectively camouflage it in nature. The short, sturdy legs are partially covered withscales corneas. Representing 30% of its total body mass, they make the little bird a skilled runner. The long bill (13 to 20 cm) and slightly curved downwards bears nostrils at its end while its base is provided with vibrissae tactile.
The southern kiwifruit: 100% New Zealand
The southern kiwifruit lives only in the part South West from New Zealand where it frequents dense and lush tropical forests and tall grass prairies. the day, it takes refuge in a burrow, a natural cavity (rock crevice, hollow of a tree) or in the undergrowth. The night, it wanders between ferns and decaying trunks in search of its sustenance. THE‘Stewart Island represents an exception because the nocturnal species prospers there for food during the day.
The poor view of the southern kiwi
Omnivorous with a carnivorous tendency, the southern kiwifruit consumes insects and their larvae (beetles, cockroaches, ants, spiders), snails and small aquatic invertebrates. During the drier months, it can be satisfied with plants (berries and fruits fallen to the ground). His poor eyesight is offset by a keen sense ofsmell andhearing to detect its prey. Thus, the kiwi probes the carpet of dead leaves with its beak provided with tactile vibrissae and nostrils. In this way the bird smells and smells vibrations produced by insects above and below the earth.
The southern kiwi, all claws out!
Of a temper discreet, the southern kiwi is difficult to observe because it is activated especially at night or during dark and stormy days. His nocturnal habits – acquired over the millennia – constitute a strategy of protection because the absence of wings makes it indeed very vulnerable to its predators. When threatened, the bird is able to swim in shallow bodies of water. This sedentary animal and territorial vigorously defends his domain by clinging to a branch with his beak and then attacking his opponents with paw kicks with its sharp claws. No one can approach the southern kiwi or its nest without suffering violent and painful cuts.
The southern kiwi, united for life
The southern kiwi is a species monogamous who remains faithful all his life to his partner. The pair isolate themselves to nest in a burrow or other natural cavity, such as the hollow of a tree, a stump or a rock crevice. The female deposits a big egg white weighing up to 430 grams, or 14 to 20% of the weight of the adult. A brood of replacement is produced in the event of failure of the first (natural death, predation, etc.). In this species, the male provides most of the incubation which lasts 84 days. At birth, the little one is adorned with a down uniformly brown, like that of his parents. Newborns are weaned in 2 to 3 weeks and then emancipate 14 to 20 days later. They reach the adult size at the age of 18-20 months and are sexually mature at 14 months for males and 2 years for females.
The southern kiwi, a vulnerable species
Dogs, cats, stoats, ferrets, swallows or even raptors are among the many predators southern kiwifruit at any age. Due to predation, a very low percentage of chicks reaches sexual maturity (we are talking about 16%). Is also involved in the decline of its population, the deforestation of its territory which reduced its workforce by 86%. The lifespan of the southern kiwifruit is 30 to 35 years in the wild. The International Union for the Conservation of Nature (IUCN) has listed the southern kiwifruit in the category vulnerable on the World Red List of Threatened Species.
Protection for the southern kiwifruit
Faced with the threats ofextinction weighing heavily on the southern kiwi, the species has enjoyed legal protection since 1896 as well as the forests in which it lives (declared natural parks). Starting in the 2000s, one measure consisted of taking eggs and chicks from the nest and raising them in captivity until a sufficient weight is obtained to allow the birds to to survive once released into the wild. These provisions have thus contributed to a significant increase in the southern kiwifruit population. At the same time, its predators are part of a management plan in parts of New Zealand.
Photo Credit: Glen Fergus