Dung beetles being deployed in battle to fight farmers' poo problem

Written by Piers Fuller

Armies of dung beetles will soon be on the ground attacking farmers' poo problems when a new South Wairarapa project gets rolling.

The regional council and the primary sector are hopeful the industrious little foreign insects can make a serious dent in pollution runoff and boost farm productivity.

Greater Wellington Regional Council has joined with Dung Beetle Innovations to subsidise packages of manure-chomping beetles to farmers around Lake Wairarapa.

Greater Wellington environment committee chair Sue Kedgley said their main aim was to improve freshwater quality.

"Managing nutrient build up and runoff is a key priority and the dung beetle option is one we are happy to support.

"Dung beetles are a natural answer to rebalancing the environmental impact of livestock. They tunnel through soil and bury livestock dung, which aerates soil, improves the nutrient cycle and helps manage water absorption and dispersion."

It is estimated 100 million  tonnes of cattle, sheep and horse dung piles up every year in New Zealand.

Waterways in Wairarapa Moana, the area in the south of the valley around the lake, have been seriously degraded over the last century by deforestation, drained wetlands and farming.

A Fonterra Open Day is being held at a Featherston farm on Sunday where thousands of beetles will be released to do their dirty work.

Through a combination of a 30 per cent subsidy from the regional council and a discount from the producer, the beetle packages are being sold to farmers at half the normal price.   The council set aside $60,000 for the project.

Federated Farmers Wairarapa branch president William Beetham said the use of dung beetles was an innovation that could really help stock farmers.

"It's been worked on for a long time and there's been  a stringent process to ensure that from a biosecurity perspective, it's safe."

"I think it's a fantastic opportunity for farmers to improve what we do."

Dung Beetle Innovations director Shaun Forgie said the key benefits were several fold.

"Especially improvements to water quality and soil structure, health and pasture productivity from the tunnelling and nesting activity of these industrious beetles.

"They play a vital role in the pastoral ecosystem, but sadly until recently have been absent from New Zealand pastures ever since we imported livestock."

Dung beetle use was approved by the Environmental Protection Agency. 

The first non-native dung beetle release in the North Island was trialled in Wairarapa several years ago.

Dung disposal unit

*There are various types of dung beetle: dwellers live in the dung, rollers roll the dung and tunnellers burrow through and into the soil.

*The species used here are tunnellers – the most effective at burying dung.

*They burrow to about 20cm deep taking manure with them.

*These tunnels creates aeration and drainage channels, which are good for pasture growth.

*It takes about 1-3 years for the beetle colony to become established.