BIRDWATCHERS are celebrating after at least two rare orange-bellied parrots reared in Victoria made a successful journey to breeding grounds in Tasmania.

Bred in captivity at Healesville Sanctuary, the pair was among six birds released near Werribee in August as part of a recovery program for the nationally endangered species.

Richard Loyn, a senior ecologist with Victoria's Arthur Rylah Institute for Environmental Research, said two sightings had since been confirmed in the parrot's traditional breeding grounds in Tasmania's remote south-west.

It is the first time captive-bred birds released in Victoria have made the flight south and been recognised individually in the island state.

Ranked among the world's rarest species, the orange-bellied parrot is a migratory bird that spends winter in coastal areas of Victoria and South Australia before heading to Tasmania to breed.

Its wild population is estimated at less than 180 birds, supplemented by about 100 in captivity.

Their welcome arrival in Tasmania was noted by volunteers involved in the state's orange-bellied parrot recovery program.

"Of the six birds we released in August, we believe that one or two did not survive the winter," Mr Loyn said.

"We now know that two, probably three, have made it to Tasmania and we are hopeful of positive news on the one remaining bird.

"We are very excited that the birds have made their own way successfully across Bass Strait and joined wild birds in a suitable breeding habitat.

"We wait with interest for more information about whether these birds remain at Birch's Inlet (south of Strahan) or move further south to join the larger wild population at Melaleuca."

Slightly bigger than a budgerigar, the parrots have bright green plumage above and yellow below – with a bright orange patch on their lower belly.

The latest release adds to wildlife experts' knowledge of how the birds operate and will help determine whether northern or southern releases are more effective in efforts to boost parrot numbers.

AAP