Year-round dung beetles improve soil and livestock health

In southern New South Wales, close to the Victorian border, graziers Jill and Ian Coghlan graze around 250 head of red poll cattle in the foothills of the Yambla range, beneath Table Top Mountain.

They've run stud cattle on their property Eurimbla for over 40 years, with a strong focus on sustainable practices, including regenerative farming.

It was through a chance meeting with Dr Russ Barrow, who was the leading researcher on the Meat and Livestock Australia-funded Dung Beetle Ecosystem Engineers project, that the couple were introduced to an otherwise unseen world beneath their feet.

Bubas Bison species of dung beetle

Together, they went to find out what kind of beetles were already present on the property and discovered a strong population of the introduced Bubas bison species, a shiny black species that emerges from the soil in late autumn and is highly valued for its ability to operate throughout the winter months. It's one of Australia's only dung beetles available that is active over winter.

While dung beetles had never been a high-priority focus for Jill, she was keen to learn more about the potential benefits the beetles could have for their overall environmental health and productivity.

What Jill and Ian quickly learnt, through regular beetle checks, was that while they had some Bubas bison beetles, they didn't have a diversity of species that would lead to stable dung processing all year around.

'It was a learning process for me, with regard to then understanding that different dung beetles operated at different times of the year,' Jill said.

'We realised there were periods of the year that we lacked the numbers of dung beetles.'

She said there was a visible difference that they hadn't considered before during the times of year the dung beetles weren't as active on their land.

'That was the noticeable thing, that the dung wasn't being 'emptied out'. They just leave a dry shell [when they're active], and that wasn't happening as much when there weren't as many dung beetles.'

Having heard the benefits to having a diverse population of dung beetles, Jill was keen to introduce new species of dung beetles to fill the gaps throughout the year and see the results they might have for soil and livestock health.

Dr Russ Barrow identified nine species of dung beetle that already called Eurimbla home, including two native species and the prominent Bubas bison species. To help fill in seasonal variance, they introduced two new species of beetles to their paddocks that suited the climate and time of year they needed.

Jill said they found, particularly in the hotter months, there were fewer dung beetles processing manure. 'Especially during summer, when it was hotter and drier, and the ground was harder, so during that period we [needed to] introduce some species,' she said.

They introduced the Onitis caffer - an autumn/winter-active species that emerges about one month earlier than Bubas bison and is also active in spring - and the summer-active Euoniticellus intermedius species.

Dung beetles can be ordered from a number of different online-based businesses, which can also help identify which species would best work for your soil type and climate.

For the Coghlans, they found that their regenerative farming system works well alongside the dung beetles' important work. Their cattle are grazed with a high-density grazing strategy, where the cattle are in a small zone and shifted to fresh feed every day.

The grazed paddocks are left for seven to eight weeks to recover, giving the dung beetles time to process the manure without risk of being crushed by hooves.

The space between returning cattle to the same area also lowers any risk of nematodes, as the dung beetles either destroy the potential manure habitat before the cattle return or consume the nematodes.

For more information on how dung beetles help reduce the risk of disease to livestock, as well as improve soil health, check out our explainer here.

The combination of regenerative farming and dung beetle support means the Coghlans can avoid using high chemical drenches. 'I think everyone's [locally] very conscious now about trying to use a drench that's compatible with dung beetles,' Jill said.

'But also with [regenerative farming plus dung beetles] we're pretty well getting rid of the worm burden, as well.'

'We still drench the younger calves, but the cows are pretty well fine to not [need] drenching.'

Dung beetles have improved our soil health and lessened our worm burden...

Because the Coghlans already had some species of dung beetles on their property, the improvements that increased populations had on the land have been subtle, but Jill says there's no denying they're there. 'Dung beetles have improved our soil health and lessened our worm burden, and with regenerative farming, the dung beetles naturally fertilise the soil and provide better water retention... They do a lot of work for us,' she said.

In late 2022, floods swept across southwest New South Wales, decimating dung beetle populations in some regions. On Eurimbla, there was significant rainfall, which also impacted their local beetle populations. 'Because we had so much rain, although it wasn't flooding here, it was enough to really reduce the number of dung beetles,' Jill said.

The result of fewer dung beetles was stark; locally, there were significant incidences of pink eye in livestock. 'The fly numbers just increased incredibly, and we had a bigger pink eye problem,' Jill said.

'It's very manageable normally, but because the flies just spread, it created this big pink eye problem, so that was a really noticeable [impact] that the dung beetles [normally control]. Jill says that as the dung beetle populations have rebuilt, so too have fly populations decreased, and that added risk of disease has dropped.

Water retention in soil has also improved over the four decades the Coghlans have been on the property, with Jill saying, in early days, after rainfall, there would be water lying on top of the flats. 'I don't think we get any runoff at all now, even with quite considerable rainfall.' Jill attributes the greater water retention to the improved soil health and aeration that dung beetles have produced, again from the increased populations of the beetles.

General biodiversity has also increased on the property - an unexpected but welcome change for Jill. 'What I see above the ground too is our bird numbers increasing - small flocks of red rumps and ibis are often seen feeding on the dung beetles,' she said. Eurimbla participates in the Birds on Farms program, where 7 rare species have now been identified.

'Our vision for Eurimbla is to provide the best habitat for the most life.'

For the Coghlans, improving dung beetle populations is an important piece of the puzzle that helps efficiently and easily improve overall livestock and soil health. 'You could have a high-input system, but why not let the biodiversity do its thing and do it well?'