Wallaby birth rate taking a leap up
ON THE HOP: Zena, a six-year-old southern brush-tailed rock wallaby, is part of the Tidbinbilla Animal Breeding Centre's program. Photo: Graham Tidy
Of the 40 southern brush-tailed rock wallabies living in captivity in Australia, 25 are housed at the Tidbinbilla Animal Breeding Centre.
So when it comes to driving population growth of this critically endangered species, the centre has an extremely important role to play.
Each year, the centre's breeding program has managed to produce more joeys than the last.
In 2011, 14 joeys were born and either released into the wild or kept in captivity for breeding.
The centre has set another new record with its 2012 program, breeding 16 joeys in captivity.
''We produce more rock wallabies than any of the other [breeding] institutes,'' acting senior wildlife officer Scott Ryan said.
''Some stay in captivity, some are kept for breeding.
''We need to constantly have new genetics and new animals and others are earmarked for release into the wild.''
Mr Ryan said the success of the breeding program could be explained by a technique the centre used called ''cross-fostering''.
The technique involves removing the very young southern brush-tailed joey from its mother's pouch and placing it on the teat of a surrogate yellow-footed rock wallaby.
Removing the young allows the breeding southern brush-tailed rock wallaby to produce another joey in 30 days.
''It means we can maximise the output,'' Mr Ryan said.
''Instead of having one joey per year, we've got females having four to eight per year.''
It is estimated that less than 40 southern brush-tailed rock wallabies remain in the wild, all in parts of Victoria.
Mr Ryan said eight wallabies from Tidbinbilla were released into the wild last year and were being tracked by Parks Victoria.
Over the past five years, 23 have been released. Some of the wallabies survive, others don't.
''Our main goal is to produce as many animals as we can to drive the release program as well as maintain genetic integrity,'' Mr Ryan said.
''I think what we're trying to do each year is just refine our skills and continue to produce lots of new joeys, and keep bringing through young animals that will become breeders in future years.
''The whole idea is to continue to release animals into the wild to get [wallaby] numbers up to a sustainable level.''