Source: Environment Canterbury Regional Council
A south Canterbury community group has looped in help from an unlikely source to improve water and soil quality in their catchment, with four shipments of dung beetles coming to their aid.
While most people actively avoid creepy crawlies, Barkers Creek Catchment Group is shipping them in by the hundreds.
The local community group was allocated funding by the Ōrāri Temuka Ōpihi Pareora (OTOP) Water Zone Committee to support their project, a catchment-wide release of dung beetles which aims to bring long-term soil and water quality improvements to the Barkers Creek area, a sub-catchment of South Canterbury’s Waihī River. The next shipment of beetles is set to be released in coming weeks.
Dung beetles and their role in agriculture
Dung beetles dine on the manure of grazing animals, including cows, sheep, alpacas and horses. The adults feed on dung before tunneling beneath the manure, then filling their tunnels with balls of dung, in which they lay their eggs. The piles of dung quickly disappear, broken down into the soils below.
By reducing run-off from paddocks into waterways, and with the nutrients being recycled back into the soil, water and soil quality is greatly improved, along with plant and animal health.
In most parts of the world, the beetles are strongly connected to livestock, but not here in New Zealand. Although we have native beetles, they have adapted to a forest environment and don’t provide any support in processing manure in our pastoral system.
Group Chair Danette McKeown said the beetles are a novel approach to an age-old problem for the small 34 sq km catchment, which is largely rolling terrain with heavy clay soils.
“Research shows they’re great on sloping land; they tunnel down so you have less dung to run off in a rainfall event, and they improve the structure of hard clays,” she said.
It’s a long-term project, as it can take five to seven years to know if the colony has become established, but Danette said the benefits are wide-reaching for the greater catchment.
“It was a no-brainer for us. Water quality was one of our priority issues as a catchment, with sediment and nutrient run-off issues because of our rolling clay terrain,” she said. “We’re also aware the closer to the source, the cheaper and more effective the remediation. So, we were looking for ‘close to the source’ mitigations.
“Dung beetles are a passive solution, they keep working for us and we can then focus our attention and funds on other things, like riparian planting and fencing off waterways.”
Community group bringing catchment-wide benefits
The dung beetle project is the latest in a long raft of successful initiatives undertaken by the Barkers Creek Catchment Group.
Made up of local farmers, they initially came together seven years ago to collaborate with us and the OTOP water zone about Plan Change 7 of the Canterbury Land and Water Regional Plan.
Today their work is driving landscape-scale improvements to the wider catchment, with current and future projects that include:
- pest control
- trapping
- bat monitoring
- regenerating native bush blocks
- and creating corridors of native riparian planting.
“We’re focused on actions with good value,” Danette said.
“If we’re going to spend money undertaking work, we want to get the widest benefits we can, so we’re focused on projects that have more than one singular outcome.”
