Five joeys are already completely independent from their mothers and weigh between 500 - 700g each, whilst all seven adult females in the sanctuary are carrying twins at different stages of development.

Greater Bilby keeper Steve Kleinig said they were amazed at the success of the program, considering the drought conditions the region experienced over the summer.

"During this time we provided extra supplement feeding to ensure the Bilbies were able to cope with the conditions," he said.

"Now that Dubbo has received some good rainfall over the past three months and the habitat in the sanctuary has improved significantly, we are seeing the bilbies gaining weight and all are now breeding."

Greater Bilby joeys remain in the pouch for around 75 days. When they emerge from the pouch they continue to be cared for by mum for a further 14 days. After this time the joeys leave the natal burrow and are completely independent.

Greater Bilbies are capable of breeding from five months of age for a female and eight months of age for a male, dependent on individual weight.

"Once mature, Greater Bilbies can breed up to four times a year if the conditions are favourable, meaning they need adequate habitat and food supply," Mr Kleinig said.

"The success of Taronga's conservation breeding program in the Sanctuary to date is a positive step towards the long-term survival of this species and to helping bring Greater Bilbies back to NSW, where they have been extinct in the wild for 100 years."

After more adults are added to the population in the sanctuary later this year, there is a plan that Greater Bilbies will be released back into the wild in 2021 as part of the Wild Desert project.

The Wild Desert project is part of the Saving Our Species program that addresses the growing number of plants and animals in NSW facing extinction.

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