Rabbit calicivirus, a biological control used to suppress wild rabbit populations, is possibly impacting graziers in western Queensland in a way they didn't expect, by increasing wedge-tailed eagle populations.
It's a theory Quilpie sheep and wool producer Stephen Tully says might account for increased numbers being reported anecdotally in the region.
Mr Tully, who has spent his working life in western Queensland, said numbers had definitely built up from very low numbers in the 1970s, when a bounty system was in operation.
"I don't think their numbers are worse now than any time in the last 20 years but I suspect they migrate in at this time every year, from where they feed up on rabbits in the Simpson Desert," he said. "It's about 20 years since calicivirus was released, so with less rabbits, they're more likely to come here looking for food."
The impact of wedge-tailed eagles on livestock enterprises isn't an issue being researched by the state's agricultural or environmental departments and so it's a theory that remains unproven for the time being, but Mr Tully said eagle predation was definitely significant.
"We continually see freshly killed and maimed animals, right up to a large-sized lamb or kid," he said. "They attack the face of the animals until they can't see, and then do the rest."
He added that goats seemed to be particularly vulnerable, which was why people were selecting animals with a red coat, to try and combat the predation.
It's a difficult issue for producers who have spent millions of dollars on exclusion fences to protect their stock from wild dog attacks, only to discover that they can't fence off the air space above their land.
Western Australian ornithologist Simon Cherriman, whose pioneering work in satellite tagging and tracking the birds has shed light on many aspects of the Australian eagle's ecology, acknowledges the difficulties faced by people trying to make a living in a harsh climate.
In his 23 years of studying them he said it was apparent that one species with two separate parts - young ones and older birds - were being encountered, which was complicating things.
He said some evidence suggested that a mosaic of breeding pairs prevented people from experiencing an influx of youthful gangs.
"The nett impact of an old established pair is less than when there's that constant invasion," he said. "The pair is likely defending their territory, but that's not unequivocal yet."
The greatest number of juveniles he'd heard of in one tree was 56.
"They are just like juveniles with nothing to do," he said. "They need adults telling them what to do."
Mr Cherriman said his GPS trackers, the first of which he attached in 2013, showed that breeding pairs took more than five years to establish, when resources were plentiful and reliable, and as juveniles eagles could fly up to 1000km in a couple of weeks.
"The problem about agricultural systems is that they create constant centres of livestock, something that only happens in boom times in nature," he said. "Eagles can accumulate in high numbers where things are good."
He said the more diversity there was in a landscape, the safer domesticated stock would be, likening it to a supermarket with one brand of cereal versus a shop with 17 different lines.
Saying that it was important to have "parts for us and parts for them" in the ecosystem, Mr Cherriman said he'd spoken to plenty of pastoralists in over 20 years of research and had found a very strong correlation between people who had lots of eagles and monocultural landscapes.
"I'd argue we should definitely keep native vegetation but the difficulty is, we don't get a quick fix - it takes small animals a decade to repopulate that," he said.
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Mr Tully said a case could be made for control measures, saying that as is the case with any animals whose numbers increase, it puts nature out of balance unless there's a correction.
Mr Cherriman wasn't so sure, saying hundreds of thousands of bounties had been paid - 162,430 in Queensland between 1951 and 1966 alone - for no return.
"Humans in Australia are influenced by a defensive mindset," he said.
"The solution 100 years ago was to kill the eagles, but it never worked.
"People spent a lot of money but they gave up.
"If you thin the population you'd expect it to go down but statistics show how, despite the enormous annual cull, it wasn't happening.
"It's just giving people a feeling they're saving their stock but they're putting their energy into the wrong places."
If it did ever get to a situation where enough young birds were killed, there would be a population crash when all the old birds died and the environment would lose its 'white blood cells', Mr Cherriman added.
"You get a cleaning service for free with eagles, so you'd have nothing cleaning up the carcases in the landscape," he said.
He was sorry that there wasn't more research being done to keep track of numbers, saying it would be wonderful to know how many more wedge-tailed eagles were around than when bounties were in existence.
"Also, was it crows and foxes causing the damage in the 1970s and was it eagles just coming in to scavenge," he said. "I've tried to establish a couple of study areas but it'd be great if there was a lot more research."