Plains-wanderers, small quail-like ground-dwelling birds with yellow legs and bills, are classified as Evolutionarily Distinct and Globally Endangered by the Zoological Society of London.

Since 2001, the number of plains-wanderers in the NSW Riverina and northern-central Victoria has dropped by 90 per cent, with estimates suggesting there are less than 1000 birds left in the wild.

A breeding program to help save the species began at Taronga Zoos in Dubbo and Sydney in 2016.

Eight birds underwent health checks before being taken to Victoria via a charter flight and then released into grasslands in Victoria's Northern Plains near Torrumbarry on October 14.

The birds have been fitted with leg bands and radio transmitters to allow researchers to closely monitor them.

The cross-state initiative includes Taronga Conservation Society Australia, Zoos Victoria, as well as Victorian and NSW government departments.

"To have zoo-bred birds being released within five years of the program commencing demonstrates the important role that zoos are playing in securing a future for species under threat of extinction," Taronga chief executive Cameron Kerr said.

"Extensive planning was required for this release with the teams from the partnering organisations overcoming challenges such as border closures."

It is the second release into North Central Victoria this year after another eight birds from Werribee Open Range Zoo were released in April.

Australian Associated Press