Keepers announced yesterday that one of its antipodean koalas has given birth to the first UK-born joey.
But the wait to hear the patter of tiny paws in the nearby panda enclosure continues with checks on female Tian Tian, who is thought to be pregnant.
Staff spotted the baby koala in the pouch of mother Alinga in May, after she was introduced to male Goonaroo.
Koala joeys are underdeveloped when born, measure under one inch in length and are deaf with no ears or fur.
Senior keeper Donald Gow 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."