Dung busters

This dung beetle is one of New Zealand’s new army of farm workers. They work 24/7, improve our soils and waterways, bind carbon, and reduce parasites and disease in farm stock. And they are paid in dung!

The photograph is of a species called Copris hispanus, one of 8 dung beetles that are being reared for release around New Zealand to reduce a smelly problem. The combined excreta of cattle, sheep, deer, pigs and poultry make for a big problem because there are no naturally occurring dung beetles in New Zealand farm paddocks. Overseas scores of species feast on the dung – cow pats are Cordon Bleu pies as far as the beetles are concerned. They lay their eggs in balls of dung which they stuff into tunnels that they dig into soil. This nutrifies and aerates the soil, feeds the soil micro-organisms, and helps the soils store more water. Buried dung is retained in the local ecosystem and is less likely to be flushed into waterways. All these benefits make dung beetles “ecosystem engineers” – crucial species that create habitat and keep the food web going.

The absence of native dung beetles in New Zealand pasture led a group of entomologist to collect suitable beetles from overseas and bring them to Auckland where they have learned how to mass rear them for spreading around New Zealand [Source]. It’s early days, but these wonderful beetles could be a game changers by solving growing environmental and social threats to pastoral farming in New Zealand. It has been brilliant and painstaking work by a small group of entomologists, and a fine example of the way ecological science can help reconstruct resilient and naturally regulated ecosystems after something has gone wrong or is missing in ecological action.

The magnificent horned beetle in the photograph comes from South-west Europe.  It’s nocturnal, has just one generation a year, and burrows up to 40 cm into the soil.  At approximately 20mm long, it’s the biggest of the 8 dung beetles approved for release in New Zealand … but hopefully still small enough to qualify for this week’s Tiny Tuesday challenge.