COVER STORY

The orange-bellied parrot may not soar like the wedge-tailed eagle nor have the Hollywood star status of the Tasmanian devil but that does not mean this vanishing species is any less worthy of our attention

Scientists make a last-ditch effort to save the rare orange-bellied parrot from the brink of extinction

The young bird, fresh out of the nest, was like any fledgling of any species: a slightly comic air, ungainly, unbalanced, unwary at the feeding station. The gentle, warm rain had given its new and growing feathers a spiky appearance, and decorating its beak and head were dots of bird seed. A young bird in summer, the new breed of the season, but this orange-bellied parrot carried a greater significance here at the end of the earth, in the southwest wilderness of Tasmania, next stop Antarctica. This young bird, along with 28 others, might well carry on its growing, developing wings the survival of its species.

The orange-bellied parrot (neophema chrysogaster) is one of the most endangered wild birds on Earth. It breeds at only one known place – amid the buttongrass at Melaleuca, in the state’s southwest within the Tasmanian Wilderness World Heritage Area, in one of the planet’s remotest places. At the start of last September, the wild population numbered just 19 birds returning from their wintering grounds on the Australian mainland to Tasmania – three females and 16 males. During the 2017-18 breeding season just passed, complex efforts had been made to boost the population with the introduction of 23 captive-bred birds.

To describe the population of the orange-bellied parrot as in free fall would be an understatement. The “free fall” in the calculation happened during the past three decades from a time in the 1980s, when numbers were counted at about 200,

to the handfuls that in the past six years have returned to Melaleuca. The reasons for the decline are not fully understood but historical habitat loss of saltmarsh in mainland states certainly is a factor.

In the early 1980s, when it first became evident parrot numbers were decreasing, the orange-bellied parrot recovery program was established, and over three decades there have been costly and time-consuming efforts to halt the decline. These have involved numerous studies, extensive monitoring, and input from federal and state agencies, universities and conservation organisations, plus an extensive captive-breeding program at zoos and private agencies to maintain the genetic diversity of an insurance population. The captive-breeding program is home to more than 300 parrots, which are kept in several facilities throughout Australia.

Despite the efforts, numbers have resolutely continued to fall. And some of those involved in the conservation effort now concede the species is functionally extinct. “We’re down to the last of the wild birds and time is running out,” says Mark Holdsworth, who headed the State Government recovery program for 22 years and is now part of the wider initiative to save the species.

“What we really need is several good years of breeding success, for the species to ultimately avoid extinction.”

Two decades ago the State Government’s threatened species unit within the Department of Primary Industry, Parks, Water and Environment (DPIPWE) established the first captivebreeding program to augment numbers at Melaleuca. It was hoped translocating adult captive-bred birds to Melaleuca in spring would boost the wild population by increasing breeding opportunities. However, over the years this has not produced a viable population of birds.

Of 64 captive-bred parrots released at Melaleuca between 2013 and 2015, 39 migrated north to mainland Australia and only a handful returned the following breeding season.

Over time, the message sank in that captive-reared birds were not migrating at the same rate as wild birds. It also became apparent that the survival rate of juveniles had also drastically declined. Somewhere between release at Melaleuca and the journey to and from saltmarshes in Victoria and South Australia, parrots were being lost. Young birds and naive captive-released ones needed the mentoring of older, more experienced parrots to learn survival skills and identify areas of suitable winter food.

At this point, the expertise of a group of researchers from the Australian National University, which had had success with another Tasmanian species on the critically endangered list, the swift parrot (lathamus discolor), was brought in to work alongside the DPIPWE.

The ANU’s Difficult Bird Research Group with its network of supporters mobilised a crowd-funding campaign to raise money for urgent intervention during the breeding season. The funds made it possible to take tiny captive-bred nestlings from the DPIPWE breeding facility in Hobart to Melaleuca to be fostered in wild nests and to rescue struggling nestlings. The crowdfunding augmented finance provided over the years by the Tasmanian and Victorian governments.

Dejan Stojanovic, heading the ANU effort, said decisions had to be made on drastic action to save the parrot, including a hands-on approach to assist in the nesting process.

“We have to face cold, hard facts,” Stojanovic said. “The time for business as usual is over. There’s nothing left to lose.”

The nestling transfers from captive to wild nests possibly proved the most dramatic intervention, an exciting but highstress venture, according to Shannon Troy, wildlife biologist for the DPIPWE Orange-bellied Parrot Tasmanian Program. In 2016, five nestlings, weighing only 3g, were taken by helicopter from Hobart to Melaleuca to be placed in nests alongside wild nestlings, or where eggs had failed. Of the five nestlings transferred, two died within 24 hours after being rejected by their foster mother, the third died of unknown causes within days of transfer, and the fourth died from a bacterial infection resulting from seed contamination at feed tables. The fifth nestling, Matilda, famously survived and made it to overwinter in Victoria in 2017, but she did not return to Melaleuca for breeding and is presumed to have not survived.

After reviewing results from 2016, Stojanovic decided the transfer of captive eggs or older nestlings to be fostered by wild parents could improve survival rates. DPIPWE supported the allocation of captive eggs for transfer to the wild, but only to nests that did not already contain fertile eggs or nestlings, to minimise the risks of disease transfer. Fortunately for the orange-bellied parrots, fertility rates were high and all nests produced fertile eggs. As a result, no nest egg intervention was needed to produce the 29 wild-born fledglings this past season.

The transfers also allowed researchers to gauge how much tolerance to nest disturbance the parrots would allow. Luckily, the breeding parrots have proven robust and not unduly troubled by the high levels of human disturbance in and out of nest boxes during the two seasons ANU researchers have been on the ground. The brief intrusions have included egg candling to determine fertility and regular nestling handling. The parrots’ ability to tolerate nest disturbance means that fostering of eggs and nestlings remain options if required in future years.

A trip to Melaleuca reveals not just nest boxes in the sparse clumps of trees amid the buttongrass. The area was once the domain of famous bushman and tin miner Deny King, who lived in a Nissen hut on the banks of Moth Creek for 55 years. He was not just a tin miner but a naturalist and ornithologist who took great delight in the annual visits of the parrots from the mainland.