Dung beetle eyes south's cow pats

20:49, Nov 24 2010
CLEANUP: Dung beetles may soon be chomping their way through Southland animal dung.

Farmers may soon have an extra weapon in their arsenal to deal with Southland cow pats and sheep droppings if a proposal to introduce dung beetles gets approval from the Environmental Risk Management Authority (ERMA).

ERMA senior communications adviser Sarah Kenward said an application from the Dung Beetle Release Strategy Group to import and release up to 11 species of beetle to manage livestock dung received 34 public submissions, with a hearing now scheduled for December 8.

Written submissions and staff recommendations would be presented, and oral submissions heard. A decision should be released by the end of February.

Strategy group spokesman Andrew Barber said the group would move quickly if approval was granted to introduce the beetles, probably from Australia, but it could be 10 to 15 years before they would reach large enough numbers to make a difference.

"It's not an overnight process."

Environment Southland had been a project sponsor so Southland was one area where releases would be made, with two cold tolerant species of beetle identified as being suitable for the south, he said.


Permission for 11 species was sought to cover the range of climates in New Zealand.

Landcare Research researcher Hugh Gourlay said the introduction and establishment of exotic dung beetles would be one of the biggest changes to New Zealand's farm management systems since cows were first imported.

"This is a bold statement but the impacts of an army of efficient dung burying beetles could be profound."

The strategy group is made up of farmers, interest groups and the MAF Sustainability Farming Fund.

A project summary from the Sustainable Farming Fund website says 5 per cent of all grazing farmland in New Zealand is covered by dung at any one time.

Introducing the beetles would allow them to "rapidly and effectively remove dung from large areas of productive land".

The beetles bury dung and use it as a food source and breeding site, eventually turning it into a sawdust-like material that improves the fertility of the soil structure.

Sheep and cattle were brought to New Zealand without dung beetles, which had evolved to process their dung, the summary says. New Zealand's native dung beetles were forest dwellers and were not found in pastoral habitats.

The stated benefits include improved soil health, improved water infiltration, reduced nutrient runoff and waterway pollution, and a reduction in greenhouse gas emissions from dung.

"Preliminary research findings suggest there will be little risk to New Zealand's environment from the introduction of dung beetles," the summary states.

The Southland Times