Creating safer skies for Tasmania's wedge-tailed eagles

Sadie Harley
scientific editor

Andrew Zinin
lead editor

University of Tasmania researchers have developed a powerful risk mapping tool to help prevent fatal collisions between endangered wedge-tailed eagles and overhead power lines.
Dr. James Pay and his team from the School of Natural Sciences analyzed six years of GPS tracking data from 23 eagles for research in the Journal of Applied Ecology. Using this data, they built a detailed model that predicts where eagles are most likely to cross power lines at low altitudes, which is where the risk of collision is highest.
The study found that eagles are more likely to make hazardous crossings in areas with a mix of open land and forest edges, particularly in remote regions. Seasonal changes also played a role, with risky crossings peaking in autumn and winter.
"Nearly 50% of known collisions occurred on the 20% of Tasmania's power line network with the highest risk," Dr. Pay said.
Over 723,000 low-altitude eagle flight steps were analyzed, with more than 9,400 power line crossings at risky altitudes.
Dr. Pay said this data was particularly valuable because power-line collisions were one of the leading causes of injury and death for large birds of prey in Tasmania and globally.
"The impact of collisions on the birds is significant, so rather than relying solely on reported fatalities, which can be biased or incomplete, we can now use the information we have about eagles' flight paths to accurately predict where collision risk is highest and act before incidents happen."

The University is working hand in hand with TasNetworks, Tasmania's electricity transmission and distribution provider, and the new model is already helping guide conservation strategies across the state.
TasNetworks' Leader of Environment and Sustainability, Ed Parker, said the business has significantly reduced bird deaths in high-risk areas in recent years, but there's more work to do and no room for complacency.
"We've already mitigated more than 600 kilometers of high-risk powerlines by installing flappers, perches and covers. We've also applied the new Delta design standard, which spreads lines further apart to reduce electrocution risk. New technologies are making a big difference.
"Our strong relationship with the University of Tasmania, and Dr. Pay's new research, will be invaluable towards our target of reducing threatened bird incidents by 25% by 2032," he said.
Dr. Pay said the model could also be used when planning new essential infrastructure and for targeted biodiversity conservation efforts, offering a data-driven approach to protecting wildlife.
More information: James M. Pay, et al. Fine-scale spatial risk models to predict avian collisions with power lines. Journal of Applied Ecology.
Journal information: Journal of Applied Ecology
Provided by University of Tasmania