Mealybugs Infestation Causing Pasture Diebacks in Queensland

Pastures in Queensland witness close to 80% dieback due to a thick shelled cocooned species of mealybugs that are feeding on them.

The mealy bug species called Heliococcus summervillei, named after the scientist who first documented its discovery in the 1920s, late Sir William Alan Thompson Summerville, is resistant to even pesticides that are used to devour them on the pastures. Australia’s leading entomologists have identified these mealybugs as the root cause for the pasture dieback in the region. What more, the infestation had occurred previously in the 20s and 30s.

Caroline Hauxwell, lead researcher, Queensland University of Technology microbiologist states, using pesticides is not a solution. “We need a long-term perpetual solution for this, not band-aids that will disrupt other pest systems in pasture. Pesticides are not the solution for this one; for large-scale control, it’s not appropriate,” she said.

The study of the mealybugs species is being put under priority to device answers to battle their growing numbers. Biodiversity with an introduction of other preying species has been underlined as of the natural solution that may see their decline. “We’re working with the Queensland Museum to identify those species and hopefully, we will be looking at their distribution and their biology to see if they can be cultured at scale,” Dr. Hauxwell said. Species like parasitic native wasps, lacewings, and some ladybeetles have been identified as its natural predator.

A legion of the country’s best minds is working to crack this mounting issue. Queensland University of Technology, Meat and Livestock Australia, Biosecurity Queensland, Australian National University, the University of Sydney, and New South Wales Department of Primary Industries have launched a multidisciplinary research into the nature and root of the problem.