It’s a delicate process. Healesville Sanctuary staff had a list of individual birds they wanted to target, for genetic reasons, and when these were captured they were anaesthetised by a mobile vet team.

The birds were microchipped, had blood samples collected and were fitted with tiny radio transmitters on their tail feathers, before being transported. To aid their recovery when they woke up, they were given orange slices.

Zoos Victoria threatened species biologist Dan Harley said this release was the result of a multi-disciplinary program to recover the species.

“Several strong years of breeding success at Healesville Sanctuary, combined with the highest number of birds ever recorded at Yellingbo has meant we can establish this new population,” Dr Harley said. “It greatly strengthens the long-term survival prospects for this species.”

Establishing this second population will increase the distribution of the rare birds so they aren’t as vulnerable to extinction through, for example, a bushfire destroying their habitat.

Finding the right kind of place to release the birds was essential. Restoring degraded habitat is expensive and takes a long time, so the team decided to search for high-quality existing native bush that would be appealing to honeyeaters.

At the new site near Warburton, a number of large, camouflaged aviaries hold the birds that have just arrived. The birds inside act as an “anchor” to honeyeaters that have already been released. When The Age visited honeyeaters often alighted on the aviaries to communicate with the birds inside.

Dr Harley says the scientists want the honeyeaters to have site “fidelity”, to create a critical mass in the nearby area rather than have them disperse through the bush.

But the flip side of that approach is that by concentrating them in one location they become conspicuous to predators. Already, a sparrowhawk has taken one of the released birds.

Dr Harley and his small team have been working to prepare this site for months, hauling metal aviary panels over the flooded creek and trying to prepare for every contingency.

“We have tried to select the right site, have the right methods for capturing and translocation and set the birds up in the best manner possible,” he says. “But what happens at that point of release is then out of our hands and that can be tough. We want it to work.”

The Victorian state government has contributed $60,000 through the Faunal Emblems Program to support this translocation and the federal government has provided $125,000 to Zoos Victoria.

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