The Midlands and its wooded areas have been an echoing cacophony of bird song for eons, but incremental landscape change has brought threats that could be silencing the music.
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Where there were once flourishing families of fairy-wrens, there are now colonies of aggressive noisy miners defending the woodland and, potentially, causing small songbirds so much stress that they can't reproduce.
University of Tasmania ecologist Glen Bain was among those growing increasingly concerned at the lack of song.
"It's just sad to go to a woodland where there's no song. There are quite a few of those in the Midlands now," he said.
"The only thing you'll get is starlings and noisy miners."
Dr Bain and a team of researchers decided to investigate. Given his expertise in fairy-wrens, he decided to use the beloved bird as a model to determine likely stress in other small songbirds in the Midlands.
PREPARING FOR THE FUTURE:
They surveyed 76 sites from Gretna to Longford, and the East to the Western Tiers - areas where birds not been studied in detail since the 1990s, when large swathes of woodland were cleared after a crash in wool prices and farmers began to grow other crops.
Their method of measuring stress may seem counter-intuitive to the scientific layperson: they captured wrens, took a blood sample and released them. In other studies, corticosterone numbers are used to determine stress, but this count could be affected if the bird is captured for more than two minutes.
Instead, Dr Bain investigated cell ratios - focusing on white blood cells - under a microscope, a method that can show long-term stress levels.
His findings confirmed his suspicions.
"The fairy-wrens in small patches of woodland on farms had stress levels nearly twice as high as fairy-wrens living in nature reserves," Dr Bain said.
"There are no noisy miners in nature reserves. They are generally found in smaller woodland on farms. Fairy-wrens living at the sites with the most noisy miners also had the highest levels of stress.
"Fairy-wrens are resilient. If these miners are affecting fairy-wrens, then they're guaranteed to be affecting other small songbirds. High stress is bad in all animals for a prolonged period. It affects the ability to reproduce and survival levels go down."
A changing ecosystem of birds in the Midlands
While things are getting tougher for songbirds, there's never been a better time for grain-eaters like cockatoos, galahs and shelducks. Researchers found sulphur-crested cockatoo numbers had increased 300 per cent in the Northern Midlands since the 90s, spreading further across Tasmania than ever before.
Corella species were also seen for the first time at many sites in Tasmania and starlings have seen a "massive increase", while carnivorous birds like ravens and perhaps even some eagles are growing in numbers.
Dr Bain said this was almost certainly a result of more Midlands farmers moving into cropping.
So what does this mean for small songbirds?
"Ravens are competing with other species. Starlings use nest hollows, so they compete with native bird species," Dr Bain said.
Woodland in the Midlands has become increasingly fragmented over time, meaning songbirds are finding themselves more isolated than before, he said.
But fairy-wrens can cover some distance in search of preferred habitat. One wren that was captured and banded north of Ross was next found south of Tunbridge over 20 kilometres away.
Dr Bain said this showed the need to establish more woodland areas to act as "stepping stones" for birds and native mammals in the search for new habitat and a mating partner.
"I think of these corridors as permanent habitat for birds. They can live there if it's good quality, and then mammals will use those areas to travel," he said.
"The key point to improving this habitat is to reduce grazing levels in existing woodland so that the midstory can regenerate and provide hiding spots for little birds, pushing the miners out. Shrubs help them to nest, forage and hide from invasive species.
"But clearing is continuing. One of the biggest challenges is the use of pivot irrigators. They can stretch over a kilometre long, taking up large expanses of land that needs to be cleared of everything, including old dead trees that can actually be an important habitat for birds.
"It's always been a problem - it was a problem 20 years ago too - but it's only getting worse because the little bit of remaining habitat in the Midlands is getting chopped up into smaller and smaller pieces."
Birds of concern - both now and in the future
Superb fairy-wrens are far from in trouble - they can rely on gardens and nature reserves.
But it's a different story for other native Tasmanian birds.
Pardalote numbers have continued to decline since the 1990s.
And most worryingly for Dr Bain, so too have the yellow-throated honeyeater.
"The yellow-throated honeyeater is endemic to Tasmania, so it can only be found in Tasmania. No one is keeping an eye on this," he said.
"If we start to see a drop here, it's not as if they can live anywhere else.
"Research is showing that common species are declining at the fastest rate. Because they're common, they have the largest effect on pollination and seed dispersal. If they drop out, it'll make a big impact."
With further research ahead, Dr Bain was confident that a not-for-profit Midlands conservation project - which provides incentives to farmers to maintain native grasses and woodland on their properties - could give greater shelter and protection to small birds.
And it might even ensure the echoing melodies of the woodland can be around for many generations to come.