Once visited by only the most serious of bushwalkers, the remote Tasmanian outpost of Melaleuca is now converged upon each summer by tourists, media and researchers keen to see, report on and better understand a single, critically-endangered species.
The entire population of the migratory orange-bellied parrot (OBP) returns every summer to a tiny pocket of the south-west Tasmanian wilderness. But every year, for decades, fewer have come home, and now they are one of the rarest birds in the world. This season, just 19 wild adults returned to Melaleuca, including only three females.
I have arranged to accompany government wildlife biologist Dr Shannon Troy on her monthly trip to Melaleuca to check on the parrots. As soon as our small plane lands on the blindingly white airstrip, Troy and her colleagues get to work removing their equipment from the cargo hold and charging off into the wilderness. I have to walk briskly to keep up as she makes her way to a nest box on the far side of the runway.
As we walk, Troy outlines the difficulty of saving a species faced with a multitude of threats. “It’s really complex,” she says. “It’s a perfect example of the ‘death by a thousand cuts’ analogy.”
Urban development and introduced weeds in their winter feeding grounds of Victoria and South Australia have led to loss and degradation of their preferred habitat. The parrots face predation from feral cats and foxes, and increased competition for food from introduced seed-eating birds such as sparrows. Changes to traditional fire regimes that once saw small patches of grassland burnt regularly, promoting the growth of new seed and opening up the low-growing sedge favoured by the parrots, means that less food is now available.
Being a migratory species, the threats affecting OBPs are spread across a wide area, making them difficult to manage. Further, with numbers in the wild so low, the impact of bushfire or disease in one location, particularly when the species congregates to nest as a single group, may affect the entire population.
While Melaleuca itself does not suffer from large numbers of predators or feral species this poses a unique challenge for conservation managers like Shannon Troy. “The most successful recovery programs for birds are often because a species is being smashed by a predator,” she explains. “We don’t have that clear link [with the OBPs] to say this is the issue and this is how we’re going to solve it.”
After walking through scrubby vegetation for a couple of hundred metres, we reach a clearing punctuated by a three-metre high timber pole bearing a large white nest box. The limbs of a tall eucalypt nearby host another of the boxes. While Troy assembles her equipment on the ground, two birds dart in and out of the box at the top of the eucalypt. I realize with a start that this is a breeding pair of the parrot I have come to see.
Soon Troy is climbing a ladder next to the pole, and as her hand reaches inside the nest box, the cheeping of four nestlings begins. They are placed gently inside a cotton bag and brought to ground so the team can check their condition and fit them with colour-coded leg bands. The leg bands will allow spotters on either side of Bass Strait to record sightings of individual birds throughout the year.
Three of Troy’s colleagues from the Australian National University join us and set about weighing and measuring each nestling. Dejan Stojanovic, a conservation biologist and part of the Difficult Birds Research Group, quickly takes blood and feather samples before the birds are returned to the safety of their nest box.
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The decline in orange-bellied parrot numbers has prompted program managers to make drastic decisions to protect the species. In 2011, after wild numbers plummeted to record lows, 21 individuals were moved into captivity to boost a captive breeding program that had been operating since the mid-1980s. With the captive population lacking strong genetic diversity, it was hoped that additions to the wild population from the breeding program would help redress this problem.
Captive-breeding populations are now kept at multiple sites including at the Hobart Wildlife Centre in Taroona and at sanctuaries in Victoria. These facilities hold a combined population of about 400 OBPs. Each year, some of these captive individuals are released to join the wild population, improve gender imbalances and boost the number of wild-born parrots.
Recognising that the species needed assistance, in late 2017 the Tasmanian government awarded $2.5 million for the expansion of the captive breeding program at Taroona. When I visited the facility recently, program leader Saint Rooks explained that the new funding would allow capacity to double from 24 to 48 enclosures and increase the number of parrots able to join their wild cousins.
The 2017-18 summer was a successful breeding season both in the wild and in captivity: 29 wild fledglings were raised at Melaleuca and 60 at Taroona. However, migratory success rates hover between 10 and 50 per cent, with the highest mortality being for females and for captive-bred birds. To prevent further losses in an already tenuous population, the decision has been made to recapture a large number of the parrots before they migrate and hold them until spring. This includes all the captive-bred parrots released last spring and all the juvenile females born this season.
Further, with long-term strategies always in mind, Troy and her colleagues are considering establishing other breeding sites in the Tasmanian south-west.
“We would like to first secure Melaleuca and know that that population is secure and self-sustaining before we go anywhere else,” she said, “but on the other hand one disease outbreak or one wildfire and we’ve lost the last population. All of our eggs are literally in one basket.”
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At a time when multiple species are facing extinction in Australia, neither Saint Rooks nor Shannon Troy understand exactly why so much political and media attention is focused on the OBP. However, as the issues affecting the OBP, such as introduced predators and habitat destruction, also impact on numerous other species, this attention has wider-reaching advantages.
Further, the high profile of the species means that attracting volunteers to assist the program is relatively easy. The role of volunteers in a wide range of conservation efforts is being increasingly recognized and both Rooks and Troy and Shannon emphasise that volunteers are key to recovery efforts for the OBP. Pairs of volunteers are stationed at Melaleuca over the spring and summer months to undertake maintenance tasks like cleaning and restocking feed stations, checking on camera trap batteries and replacing memory cards. Perhaps most importantly they collect data on the movement and visual appearance of the birds, as well as on the presence of predators and competitors at the site.
“The data they collect underpins everything that we do and the decisions that we make,” said Troy. This allows researchers to make decisions around captive breeding efforts or associated management actions such as health screening and removal of predators. Occasionally, volunteers help staff at the captive facility in Taroona with tasks like preparing bird enrichment activities or cleaning aviaries.
In fact, the program is inundated by volunteer applicants each year, and several have volunteered for more than one season. Bernadette Camus volunteered at Melaleuca in 2016 and again in 2017. “It becomes difficult to pick a single highlight from so many incredible experiences,” she said. “I will never forget however, the excitement of sighting a new arrival. On the second trip, the anticipation felt greater because I had come to know the birds so you were always hoping to see a familiar face, knowing the perilous journey they make.“
With so much effort going into the program, and considerable community support behind it, it is no surprise that Shannon Troy, Saint Rooks and Bernadette Camus feel some optimism about the future for the orange-bellied parrot. “We’re having a promising season this year in the wild and in captivity,” said Rooks, “so there’s light at the end of the tunnel for the OBP.”
At the end of summer, after the last parrot had headed north, controlled burning of the buttongrass plains at Melaleuca was undertaken for the first time in years, ensuring a better food supply for the species upon their return in spring. With expansion of captive breeding capacity and by preventing a proportion of the population from making the perilous migration, it is hoped that orange-bellied parrot numbers will be bolstered for next summer.
“I’m hopeful this will be a good year,” Shannon Troy said, “but we need a few of them in a row.”
The Wildcare Friends of the OBP group undertakes work throughout the OBP’s range. Learn more by visiting wildcaretas.org.au/branches/friendsobp
Grace Heathcote is a Tasmanian freelance writer. After a childhood spent exploring the forests and beaches of Tasmania, she left the island in 2007 to study, work, and travel through Australia and overseas. The charm of Tasmania lured her home in 2014 and has continued to weave its magic for her ever since.