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 analysed six years of GPS tracking data from 23 eagles for research published 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 per cent of known collisions occurred on the 20 per cent of Tasmania's power line network with the highest risk," Dr Pay said.
Over 723,000 low-altitude eagle flight steps were analysed, 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.
"Between 2017 and 2023, 110 wedge-tailed eagles were confirmed as injured or killed by power line infrastructure in Tasmania," he said.
"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.
"Our people are very passionate about protecting iconic birds, and we invest almost $1 million each year," Mr Parker said.
"We've already mitigated more than 600 kilometres 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 per cent 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.
See the full journal article: https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.70076
