In the remote interior of Australia, helicopters still fly low over red soil, shooting at wild donkeys that authorities have long labeled a feral menace.
For decades, these animals have been blamed for smashed fences, trampled riverbanks, and competition with cattle at scarce waterholes, and mass aerial culls have removed hundreds of thousands of them from regions like the Kimberley in Western Australia.
At the same time, research in the journal Science and in follow-up field studies is quietly telling a different story. Wild donkeys and horses in drylands can dig deep wells with their hooves, bringing hidden groundwater to the surface and creating small oases that other species rely on.
In North American deserts, these equid wells have supplied water to nearly sixty vertebrate species and sometimes provided the only surface water in a stretch of streambed at the height of summer.
So which is it? Are wild donkeys wrecking the outback, or helping to keep it alive as heat and drought intensify? The emerging answer is that they can do both, and that what really matters is how many there are, and where they are allowed to roam.
From villains to reluctant allies
Australian governments have long treated donkeys as invasive livestock that escaped their original role as pack animals. National reviews list problems such as gully erosion, damage to wetlands, and competition with native herbivores when populations boom and animals crowd around fragile waterholes.
But ecologists now point out that the same hard hooves and tough bodies that cause damage at high densities can also perform useful work when numbers are kept in check.
In the Sonoran Desert and Mojave Desert, camera traps show donkeys digging wells up to two meters deep, increasing the density of water points and drawing in birds, deer, small mammals, and even predators that come to drink. Abandoned wells often turn into nurseries for cottonwoods and willows, key trees that stabilize banks and shade streams.
Researchers at University of Technology Sydney and collaborators argue that modern feral equids are acting as “ecosystem engineers”, reviving a role once played by now extinct megafauna that also dug for water in ancient drylands.
What this means on Australian farms
Australia hosts one of the largest wild donkey populations in the world, particularly in arid and semi-arid rangelands. That has created deep tension for graziers who watch stock dams shrink, dust storms creep closer to homesteads, and at the same time worry about feral animals breaking infrastructure and eating scarce pasture.
Some landholders are starting to test a different model. On properties such as Kachana Station in the Kimberley region, small, monitored groups of donkeys are being kept instead of shot, then guided through the most degraded paddocks.
Managers report that the animals open up hard capped soils with their hooves, dig for water in dry creek beds, and leave dung that carries seeds and nutrients, helping scattered grasses and shrubs to return.
For farmers staring at rising costs to run heavy machinery and pump groundwater, the idea of a “biological tractor” that runs on scrub and instinct has obvious appeal. It is not a magic fix, but it could become one more tool alongside rotational grazing, erosion control works, and careful fire management.
Control, not chaos
None of this means turning millions of donkeys loose and hoping for the best. The science review on free-roaming donkeys published in the Journal of Wildlife Management stresses that their impacts are highly context dependent and can be strongly negative in sensitive habitats if populations are not controlled.
That is why researchers and some conservationists are now talking less about eradication and more about zoned management. In practical terms, that means limiting herd sizes to what each landscape can support, fencing wetlands and cultural sites that need strict protection, and concentrating the animals in already degraded areas where their digging and trampling can help water soak in and plants recolonize.
The debate is far from settled. Many ecologists and Traditional Owners remain deeply concerned about the pressure that feral herbivores put on native species, and court cases around experimental donkey projects show how contested this new approach still is.
Yet in a drying continent where every extra pool of water and every patch of living soil matters, the idea of turning yesterday’s pest into a tightly managed ally is gaining ground. The wider conversation about “invasive” species is shifting too, as some scientists call for conservation models that look at function and ethics as well as origin.
At the end of the day, the future of wild donkeys in Australia may come down to a simple question that farmers, policymakers, and communities will have to answer together. In a hotter, drier world, is it smarter to keep spending money on bullets, or to spend it on science-based management that harnesses the animals’ strengths and limits their harm?
The study was published in Science.
