Charles Sturt University (CSU) research has shown the harmful effects of a toxic weed on kangaroos, prompting calls for strategic investment to control invasive plants in grasslands.

Key points:

• CSU research reveals harmful effects of a toxic weed on kangaroos, following investigation into death of nearly 100 eastern grey kangaroos in the Riverina in 2014.
• Kangaroos had been grazing on a pasture dominated by an invasive species of panic grass that is known to cause photosensitisation in sheep but this is the first time it’s been documented in kangaroos.
• Kangaroos showed clinical signs of blindness, photophobia and dermatitis and post mortem showed jaundice caused by liver damage.  
• Need strategic approach for research and management to deal with the impact of invasive plants on wildlife

Scientists from CSU’s School of Animal and Veterinary Sciences, Veterinary Diagnostics Laboratories and the Graham Centre for Agricultural Innovation, investigated an event that killed nearly 100 eastern grey kangaroos in the Riverina region of NSW in 2014.

Senior lecturer in veterinary pathology, Dr Andrew Peters said the kangaroos had been grazing on a pasture dominated by an invasive species of panic grass.

“Panic grass is known to cause photosensitisation in sheep but this is the first time it’s been documented in kangaroos,” Dr Peters said. “The affected kangaroos were showing clinical signs of blindness, photophobia and dermatitis and the post mortem examination showed jaundice caused by liver damage. The kangaroo deaths occurred shortly before an outbreak of photosensitisation in sheep in the region.”

Dr Peters said the research published in the Journal of Wildlife Diseases is also significant because it is only the third confirmed case of invasive plants killing Australian wildlife.

This documented case of kangaroo deaths caused by an invasive weed is like the ‘canary in the coal mine’.

“What is concerning is that we may be missing other events that involve smaller and less obvious mammals. We also have very little understanding of the effects of chronic disease or poor nutrition from invasive plants on our wildlife.

“What is clear, as introduced weeds increasingly invade our ecosystems, is that we need to pay more attention to their impact on native animals.

“Land managers at a regional level need to be aware of the scale of landscape change and there needs to be a strategic approach to research and intervention to deal with the impact of invasive plants on wildlife,” Dr Peters concluded.