A pair of rare tree kangaroos has started a family at the National Zoo and Aquarium in Canberra, with the arrival of little Mani.
Goodfellow's tree kangaroos are rarely bred in captivity and the new joey is an important boost for an international conservation program.
Tree kangaroos are critically endangered due to predators in far-north Queensland and illegal forestry in Papua New Guinea.
Senior keeper Shelley Russel says the tree-dwellers are hard to breed.
"We have been lucky to have a pair that like each other, a lot of zoos sometimes don't have that," she said.
"No one really knows what the special recipe is or what's stopping the other zoos from breeding.
"We'd like to think it's our expertise, but I'd say it's just our pairing was good."
Mother Oumak and father Kubu were paired in 2012 as part of an international breeding program.
Ms Russel says they then came up with a formula for following Oumak's oestrous pattern to increase the chances of a successful mating.
"Our male is very friendly so we could rub our hand on him and then offer our hand to the female and her reaction would tell us if she was wanting him to be around," she said.
"The reaction was quite incredible, because she's a very shy animal.
"So the only time you got to pat her was when she was rubbing herself all over the scent of him on your hand.
"We would then put them together and over the following days hope there'd be a mating."
Zookeepers anxious ahead of new arrival
Their second attempt was successful, and for a few months the joey's arrival was a bit of a guessing game.
"The first time around, we sort of thought something was going on, but there wasn't," Ms Russel said.
"So the second time around we were all a bit nervous about actually saying she's got something in her pouch.
"But it wasn't too long. When the baby was about two months old we started to see a bit of kicking and moving."
The joey will stay in its mother's pouch for at least 18 months.
"After that the little one is destined to go on its own little breeding program," Ms Russell said.
"We don't know if it's a male or female yet. As soon as we find that out, the coordinators for this species will be pairing it up and getting it placed at a zoo."