It was a birth announcement of some significance, even if it didn't come from the panda enclosure.

Keepers today declared that the UK's first ever koala joey has been born at Edinburgh Zoo.

First time mum two-year-old Alinga arrived at the zoo earlier this year, before being introduced to male Goonaroo in April.

Koalas have a gestation period of only 30-35 days and the birth of the joey is thought to have taken place in mid-May.

However, koala joeys are extremely underdeveloped when first born - measuring about an inch long, blind, with no ears and no fur - and spend a further six months growing inside their mother's pouch.

The pouch has a powerful muscle to prevent the joey from falling out and, in addition to milk, the joey will suckle on a substance called 'pap', a special type of dropping produced by the mother which contains vital micro-organisms necessary for digesting eucalyptus leaves when it is older.

Edinburgh Zoo is the only one in the UK to have koalas and this new arrival is seen as testament to the zoo's expertise, animal husbandry and experience that this species requires.

The zoo has been part of the European breeding programme for eight years and has originally housed young male koalas until they were sexually mature and moved to other collections for breeding.

Alinga is the zoo's first female koala and to have successfully bred with her so quickly is an immense achievement for the keepers.

The joey currently weighs approximately 100g and is expected to first pop its head out of the pouch by mid-October.

The joey will start to climb onto Alinga's belly around mid-November - when it weighs around 400g - and this is when visitors are likely to be able to see it.

Around December it will then move onto her back and zoo keepers will weigh, sex and name the joey.

Alinga will carry the joey around on her back until it is around 12 months old. Once the joey is sexually mature it will join the European breeding programme.

Donald Gow, senior keeper at Edinburgh Zoo, said: "We are all immensely excited by the birth of the UK's first ever koala joey. I have worked with the zoo's koalas for the past eight years and they require a lot of specialised care. Koalas are very sensitive creatures with a very selective diet and the husbandry can be extremely challenging.

"As they are solitary animals, it takes an expert eye to know how to successfully introduce a male and female together for breeding. There is a lot of dedication and skill involved in caring for koalas, and it is a significant achievement for everybody involved."

Koala numbers are in decline throughout the eastern coast of Australia due to habitat loss and it is very significant for a successful breeding programme be established outside of Australia. The birth of the UK's first koala joey will help cement Britain's role within this breeding programme as well as raise awareness on the need to protect this species.

Alinga and her joey - along with the two male koalas, Goonaroo and Yabbra - can be seen at the newly revamped Koala Territory.

The zoo is also hopeful that giant panda Tian Tian will give birth soon, having shown signs of advanced pregnancy.