After a 15-month pregnancy, "outgoing" giraffe Rosie gave birth to the long-awaited, lanky addition to the zoo's giraffe herd on Tuesday.

“Rosie is a beautiful mum and this is her third calf she’s had here at Australia Zoo, so she’s relaxed and knows exactly what to do," Head of African Animals Manu Ludden said.

“Rosie and her new baby to are now bonding and spending some important one-on-one time together.

"In the coming weeks, we would expect to slowly introduce them into the rest of the herd on the African Savannah where guests will also be able to see them."

The baby giraffe is highly prized as endangered populations of wild giraffes face threats to their future.

"Mother Rosie is doing a great job with her new baby," Bindi Irwin said.

"Both little one and Mum are happy and healthy. We are excited to share this fantastic news with everyone.

"This gorgeous girl is certainly going to melt a lot of hearts with her big brown eyes."