Decades ago, it wasn’t possible to sit outside a Canberra cafe on the footpath and enjoy a bite to eat without your meal being overtaken by unwelcome diners.
According to John Feehan, that has changed thanks to the introduction of a variety of dung beetle species.
“If you go back 30 years ago or so it was actually illegal for a restaurant or a café to put a table outside on the footpath and serve any food whatsoever,” he said.
And that was just as well, because if you had, “200 bush flies would descend on whatever you were attempting to eat,” Mr Feehan said.
“Now here in Canberra because there are up to seven species of dung beetles established, people eat outdoors in Canberra just as people do in London, Paris, and New York.”
Now, farmers in the ACT are being encouraged to introduce dung beetles for a secondary reason — namely, to enrich their soil and save on fertiliser.
With more than 28 million cows in Australia, each producing around 12 cow pats a day, close to half a million tonnes of cow dung is being dropped on the continent daily.
Australia has hundreds of native species of dung beetle that are able to handle the excrement of native marsupials like kangaroos and wombats, but most are unable to cope with the large quantities produced by introduced livestock, in particular cows.
Cow dung build-up can cause significant ecological and economic damage for cattle farms — attracting flies that increase the spread of pests and disease, causing chemicals and organic matter to flow into waterways, and reducing pasture soil quality and productivity.
When dung beetles eat and then bury cow dung they also bury the nutrients — like nitrogen and phosphorus — in it, rejuvenating the soil.
Mr Feehan, a dung beetle expert, said using the beetles as a biological resource in pasture land was both effective for improving soil quality and cheaper in the long run for farmers than buying fertilisers.
“The beetles dig a tunnel system and they go down directly under the dung, then those tunnels will radiate outwards roughly into the area of a bicycle wheel,” Mr Feehan said.
“We’re virtually rejuvenating a bicycle wheel area underneath every well-buried cow pat.”
Mr Feehan was involved in the CSIRO’s dung beetle project, which saw 53 species introduced to Australia from southern Africa and southern Europe between 1968 and 1981 to be used as biological resources.
Of those, 24 imported dung beetle species are known to still be established in Australia — seven of those in the ACT.
One-off cost for generations of benefit
Mr Feehan, who runs a company that supplies the beetles to landholders, said many farmers had got in touch afterward to say how valuable the dung beetles had been.
“A new species of dung beetle will cost part of one single tonne of phosphate fertiliser, and the farmer will eventually get 1,000 times greater benefit out of one new species of dung beetle than they ever would out of one tonne of phosphate fertiliser,” he said.
“So there is a great need to recycle the valuable nutrients – the nitrogen and the phosphorus and other trace elements – in the dung, and put them back into the grass root systems.
“If farmers look after their beetles — and it’s a very simple matter to look after them — then that species will be established on their farm for their grandkids. It’s a one-off cost and it will remain on the farm forever.”
Another benefit using dung beetles as a biological resource is their ability to reduce fly populations.
“The buffalo fly larvae and the bush fly larvae each require five to six days to mature, so if we bury the dug within that five to six-day period we can reduce bush fly and buffalo fly numbers significantly,” Mr Feehan said.
He said research done into the impact of the CSIRO project revealed a reduction of 99 per cent in bush fly populations.
Dung beetles ‘intricately linked’ to regenerative agriculture
The ACT government, through the ACT Natural Resource Management (ACT NRM) team, is currently running a program to encourage and assist farmers in establishing dung beetle populations on their pasture land.
ACT NRM sustainable agriculture program lead, Jarrod Ruch, said there was significant interest in the ACT dung beetle program.
“It would be very rare to hear of a farmer who’s not interested in dung beetles,” he said.
“I think the more farmers know about it – and are aware of the great value of the dung beetles – the more they come on board.”
Mr Ruch said the dung beetles were “incredible soil engineers” that can smell dung from up to a kilometre downwind, and using them as a biological resource had a net carbon benefit.
“In an overall regenerative agriculture framework of practice we look at a number of parameters to try to move into continuous improvement,” he said.
“Some of those parameters are water, landscape rehydration, some of them are soils, carbon, animal welfare.
“You can see the dung beetle is intricately linked into all of those parameters because they’re sequestering carbon, they’re improving soil, they’re rehydrating landscapes, and they’re increasing the animals’ welfare.”
Mr Ruch said over the next few years the ACT NRM would be working to assist the naturalisation of some species that were not yet established in the ACT.
“Ideally we’ll have dung beetles active every month of the year — which gives the farmer a broader season of dung beetles’ activity — with the ultimate aim of improving soils and being able to rehydrate landscapes,” he said.
A ‘satisfying’ half century working with dung beetles
Mr Feehan said the purpose of importing dung beetles was to “create a balance now that began to occur with the arrival of captain Phillip – and he had with him sheep, cattle, horses, pigs and chooks”.
“What we’re trying to do with the dung beetles is balance something now that the arrival of European settlement and the introduction of domestic stock created,” he said.
He said seeing dung beetles rejuvenating pasture land for half a century through his work was incredibly satisfying.
“I can walk around some cattle properties where there are thousands of head of cattle [and] there are no bush flies in the Summer months, no buffalo flies, and no dung in the paddocks,” Mr Feehan said.
“So after 50 years of working with dung beetles it’s a very satisfying experience.”
