Recently, in Planckendael (Belgium), a koala baby has regularly been seen poking its nose out of its mother’s pouch. Yet six months have already passed since the birth of this koala. Now how does that work?
Koalas are marsupials. A short time – for koalas, 34 days – following fertilisation, a very underdeveloped koala baby is born. The animal is then about 2 cm in size and is naked, hairless, blind and pink, yet this mini-koala can already find its way to the pouch. Here, the baby animal latches onto a nipple and continues to grow and develop. Six months after birth, the young has developed enough to show itself regularly, though it remains in the pouch. Over the course of several months, the young animal will also move to the mother’s back. Where at first the koala baby drank only milk, now the mother feeds it a special ‘pap’ from the mother’s cecum, containing bacteria necessary to the koala’s stomach and intestines for digesting eucalyptus leaves. A koala’s diet consists of eucalyptus leaves alone, but not just any kind: they eat the leaves of only 100 of the 800 existing eucalyptus species. In Planckendael, approximately 30 different species of these trees are grown and used as feed from May to October. The rest of the year, eucalyptus leaves are imported from the United Kingdom.
Koalas are not kept in many zoos. They are choosy eaters, and sensitive to stress as well. In Europe, they can be seen in seven zoos. Planckendael also participates in an international breeding programme; this is the eighth young koala to be born there.