RECENT reports of buffalo fly in the Central West have prompted calls for farmers to introduce more varieties of dung beetles to their properties.
Establishing eight or more dung beetles species can eliminate the breeding ground for buffalo and bush fly, according to Canberra-based entomologist and dung beetle expert John Feehan.
“The bush fly larvae require about six days in an undisturbed cow pat,” Mr Feehan said.
“If dung beetles fly to that fresh dung, feed on it and bury it in 24, 48 or 72 hours, they completely remove the breeding ground for the bush fly.”
A buffalo fly, slightly smaller than a bush fly, completes its larval development in four to five days, depending on temperature, Mr Feehan said.
“They both breed in cow dung and they both live on left-over protein, vitamins and minerals in the dung so if you bury dung quickly, you can stop buffalo fly from breeding,” he said.
“It’s a relatively simple matter, but to do so you do need six, eight or even 10 different species established on a farm so that no matter what the weather conditions are, some of those species will be working and burying the dung.
“Sometimes when the dung beetle population is at a low level and they’re not quite burying the dung, they shred the dung – they scatter it and it looks like a pile of sawdust.
“Particularly up in the northern part of NSW in the summer, once they break that crust on the surface of the dung, that allows it to dry out and despite the fact the beetles are not burying all of it, they’ve shredded it and the summer sun will take care of the drying out, which also prevents the buffalo fly from breeding.”
It’s a natural method of controlling flies in a country where about half a million tonnes of dung is produced by cattle each day, but there are also big benefits for soil fertility.
Mr Feehan said beetles aerated the soil, allowing nutrients and moisture to filter through the soil.
“When they put the organic matter under the ground they’re putting the nitrogen that’s in the dung under the grass roots, but when dung sits on top of the ground 80 per cent of the nitrogen in the dung goes off into the atmosphere,” Mr Feehan said.
“When dung beetles bury the dung, that figure is reversed.”
Beef producers John and Carol Richard have introduced eight species of dung beetles to “Cooinda”, Cassilis since the 1970s. They said the dung beetles had improved soil health, making the 610-hectare property more productive and reducing the number of flies.
They introduced their first winter species last year.
“Since introducing the dung beetles we’ve had hardly any flies and they’re also good for the sheep and cattle worm burden,” Mr Richard said.
Their next focus is finding a dung beetle that will work in a dry season.
“In spring they can bury a pat in a couple of hours, but they’re a bit slower in winter and as soon as we get a dry period they stop working here,” Mr Richard said.
