Koalas are considered a vulnerable species. Their population was decimated from hunting for their fur during the 1900s, and koalas are still in danger from human encroachment upon and destruction of their habitats as well as disease. Chlamydia, which infects many koala populations, makes the female koalas infertile.
Koalas eat the leaves of certain eucalyptus trees . A koala can digest as much as 1.3 kg (3 pounds) of leaves daily, and it has an intestinal pouch about 2 metres (7 feet) long, where symbiotic bacteria degrade the tannins and other toxic and complex substances abundant in eucalyptus. This diet is relatively poor in nutrients.
Koalas are found in eastern Australia. Their habitats require the eucalyptus trees on which they feed and in which they live.
Though sometimes called a koala bear, the koala is not a bear. The koala is actually a type of tree-dwelling marsupial, with a backwards-facing pouch, like wombats.
koala, (Phascolarctos cinereus), also called koala bear, tree-dwellingof coastal eastern classified in the family Phascolarctidae (suborder Vombatiformes).
The koala is about 60 to 85 cm (24 to 33 inches) long and weighs up to 14 kg (31 pounds) in the southern part of its range () but only about half that in subtropical to the north. Virtually tailless, the body is stout and gray, with a pale yellow or cream-coloured chest and mottling on the rump. The broad face has a wide, rounded, leathery nose, small yellow eyes, and big fluffy ears. The feet are strong and clawed; the two inner digits of the front feet and the innermost digit of the hind feet are opposable for grasping. Because of the ’s superficial resemblance to a small , the koala is sometimes called, erroneously, the koala bear.
The koala feeds very selectively on the leaves of certain. Generally solitary, individuals move within a home range of more than a dozen trees, one of which is favoured over the others. If koalas become too numerous in a restricted area, they defoliate preferred food trees and, unable to subsist on even closely related species, decline rapidly. To aid in digesting as much as 1.3 kg (3 pounds) of daily, the koala has an intestinal ( ) about 2 metres (7 feet) long, where symbiotic degrade the and other toxic and complex substances abundant in eucalyptus. This diet is relatively poor in and provides the koala little spare energy, so the animal spends long hours simply sitting or sleeping in tree forks, exposed to the elements but insulated by thick fur. Although placid most of the time, koalas produce loud, hollow grunts.
The koala is the only member of the family. Unlike those of other arboreal marsupials, its pouch opens rearward. Births are single, occurring after a of 34 to 36 days. The youngster (called a joey) first puts its head out of the pouch at about five months of age. For up to six weeks, it is weaned on a soupy predigested eucalyptus called pap that is lapped directly from the mother’s anus. Pap is thought to be derived from the . After weaning, the joey emerges completely from the pouch and clings to the mother’s back until it is nearly a year old. A koala can live to about 15 years of age in the wild, somewhat longer in captivity.
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Formerly killed in huge numbers for their fur, especially during the 1920s and ’30s, koalas dwindled in number from several million to a few hundred thousand. In the southern part of their range, they became practically, except for a single in , Victoria. Some were translocated onto small offshore islands, especially , where they did so well that these koalas were used to restock much of the original range in Victoria and southern . Though once again widespread, koala populations are now and separated by urban areas and farmland, which makes them locally to . Another problem is the infection of many with , which makes the females infertile.
The(IUCN) has listed the koala a species since 2016. The species decreased by nearly 28 percent between the years 1984 and 2012, largely because of habitat loss and fragmentation, which made the animal more susceptible to vehicle strikes and predation by . and also contributed to the decline in the koala population. As temperatures increase and the drying effects of become more pronounced in Australia, wildlife officials expect that the koala population will decline further in the coming decades.
Koalas 101 | Nat Geo Wild
Koalas are not bears—they’re marsupials. Learn about koalas’ unique traits, including six opposable “thumbs,” downwardfacing pouches, and an ability to sleep nearly all day in tree branches.
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Koalas 101 | Nat Geo Wild
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