The biggest factor is the environmental conditions and severe weathers. Sometimes, the mating is only valid for the bigger dominant Koalas, but these happenings are relatively far and few among koalas as no matter how much bigger a koala is, it prefers to sleep 20 hours a day, while other koalas can specifically seek opportunities of mating. Still, wild breeding has serious challenges.
Much of the appropriate habitat has already burned, or is likely to burn in the coming decades as climate-driven wildfires intensify. When scientists later surveyed field sites across eastern Australia to look for surviving koalas, they found that the fires had eliminated about 71 percent of the populations there. Some sites seemed to have no koalas at all.
Koalas likely fared worse in the fires than any other iconic Australian species. Kangaroos can flee; wombats can burrow. But the koalas are in the canopy. As many as 70 percent of koalas might be infected, and 90 percent of those animals are infertile. Scientists such as Stephen Johnston, a zoologist at University of Queensland, think they can improve productivity in captivity.
Their offspring alone would be insufficient to restock wild populations. Moreover, breeding is only half the battle. The greater challenge for wildlife managers will be ensuring the captive-born offspring can survive in the wild by finding safe, suitable release sites. Port Macquarie Koala Hospital hopes to keep as many as 60 koalas on site for eventual release back into coastal areas. Flanagan says the plan is to mate mostly nonreleasable wild koalas with one another. These will be disease-free individuals brought into the clinic for various injuries and that, once recovered, cope well in captivity.
Furthermore; the male koalas also tend to mark trees with their scent marking which is released from their chest and they also mark the trees with their claw marks as well. The purpose of this overall activity is to let the other males to stay away from their territory. Occasionally; the territorial conflicts also occur in between the male koalas which are usually brief but decisive.
On the other hand; the female koalas are quite receptive to the loud vocalization of the male koalas during the mating season. Usually the female koalas greet the male koalas with a low snarl or a weak bellowing. Whenever the male koalas approach the female koalas, females are mostly reluctant and tend to struggle away from the male koalas.
On the other hand; the female koalas with babies are often very aggressive towards the male koalas and a quarrel may erupt between the male and female koalas, if the male tries to breed.
The joeys having an ability to come out of pouch with the females often cling to the back of their mother during the fight while the joeys less than 6 months old tend to remain inside the pouch. The breeding season also allows koalas to become a bit social as well. All baby marsupials have a very interesting life, from the moment they are born to when they leave their mothers to make their way in the world of the Australian bush. When the mother Koala gives birth, the little joey Koala makes its way to the pouch all by itself, with no help from its mother.
One of the most amazing things about this is that the Koala joey is blind when it is born, and relies totally on its well-developed senses of touch and smell and strong forelimbs and claws to help it get to the pouch.
The new-born joey weighs less than one gram and looks something like a pink jellybean. It is roughly 2cm long, blind, hairless, and looks very different to the cute, fluffy little bundle that it will become later.
When the joey is about months old it is ready to begin weaning from milk to gumleaves. To do this, the mother Koala passes on the micro-organisms in her stomach that are necessary to make the digestion of gumleaves possible to her joey.
As soon as it begins its diet of gumleaves, the young Koala grows at a much faster rate, becoming more adventurous as it grows bigger and stronger. Eventually, the young Koala will begin to make short trips away from its mother.
From 12 months onwards, Koala joeys leave their mothers to find their own home ranges.
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