Before humans settled, New Zealand's forests were full of xiāo parrots, which mean "night parrot" in Maori. Unlike any other parrot species in the world, these strange birds do not fly and are nocturnal on their own. However, for a parrot weighing 4 kilograms, they are also incredibly heavy. They are the longest-surviving birds, living to be 90 years old or even longer. They run along the forest floor, climbing trees with their strong beaks. The Owl is a unique species and is a unique member of a subfamily of itself.
This incredible species was once important in Maori culture, but the arrival of Western settlers puts the species in grave danger. With their arrival, domesticated animals and land predators previously unknown to owl parrots, due to their inability to fly, proved to be very easy prey for these new species to catch.
This incredible species was once important in Maori culture, but the arrival of Western settlers puts the species in grave danger. With their arrival, domesticated animals and land predators previously unknown to owl parrots appeared, and since they could not fly, they became one of the very easy prey for these new species.
By the 1970s, the species' population had become so low that it was widely believed that the species would not be able to recover. However, in 1977, an isolated population of 200 was found on Stewart Island, which was free of ferrets and weasels, but the population declined due to the predation of wildcats.
Following this astonishing discovery, volunteers and scientists set up intensive breeding programs on several remote islands far from mammalian predators, dedicated to witnessing the species survive a long period of extinction. The remaining Stewart Island Owl parrots were relocated to these islands.
The breeding of owl parrots is unusual, to say the least. They are the only parrots that breed in courtship grounds, where males gather and perform against the watching females. Males inflate their thoracos balloons and make loud cries to attract females. During the breeding season, this condition can last up to 3 months per night. The female then chooses which male to mate with, lays 1 to 4 eggs, usually hatches after 30 days, the chicks are covered with gray fluff, the female owl parrot will continue to feed for about 3 months alone, because the owl parrot is a nocturnal animal, so the female owl feeds the young chicks with vitamin D-rich berries on a New Zealand wood tree. However, these trees only bear fruit once every three years, which means that the breeding of owl parrots is limited to those years. Such low reproduction rates make intensive breeding programs even more important.
Another data on the breeding system of the Owl is that female parrots can change the sex ratio of their offspring according to the condition of their mothers. When female owl parrots eat more protein-rich foods, they give birth to male-dominated offspring (males are generally 30 to 40% heavier than females). As a result, female parrots will still give birth when food or resources are tight, but will prefer to give birth to a single sex so that the sexes within the population can be dispersed (e.g., concentrated in female offspring), and not when the amount of food is abundant. Male parrots mate with different females when food is plentiful to achieve the natural mission of species continuation. This study supports the Travis Verla hypothesis, which is controversial in evolutionary biology. This study of the sex of offspring, which is related to maternal weight status, has important implications for childcare programmes. Because the provision of complementary food to increase the reproduction rate will also reduce the chance of birth of the offspring of the more conservative female birds, it is necessary to strictly control the mother's condition to achieve a win-win situation.