High-flying life of Australia’s birds revealed in new detail – thanks to weather radars

In a groundbreaking study that could significantly impact conservation efforts as windfarms increase, researchers have unveiled detailed insights into bird migration patterns along Australia’s east coast. This study, utilizing weather radar technology traditionally used for tracking atmospheric conditions, marks the first comprehensive look at the annual migration routes of birds in the region.

According to lead author Shi Xu, a PhD candidate at the University of Queensland, the radar technology allows scientists to “observe how birds, insects, or bats take flight and navigate through the air.” He emphasized that the radar quantifies aerial movement in a manner akin to measuring rainfall, revealing structured patterns of migration.

The research, published in Current Biology, analyzed years of radar data, identifying two primary migration pulses: one occurring northward from January to June and the other southward from July to December. The study found that during autumn, an average of 60,000 migrating birds per kilometer traveled along the east coast each year, based on data collected between 2018 and 2022.

Co-author Professor Richard Fuller, also from the University of Queensland, highlighted the significance of this research in the context of ongoing windfarm developments. “Understanding the pathways of bird migration across regions like Queensland and Tasmania is critical,” he noted. “Birds connect these landscapes, so it’s essential to have a coordinated conservation strategy.”

Interestingly, the study revealed a notable difference between Australian bird migration and that of the northern hemisphere, where migration is largely nocturnal. The researchers observed substantial daytime migration activity, a phenomenon they suggest may be unique to Australia. Sean Dooley, national public affairs manager for BirdLife Australia, underscored the variability in migration timing and direction, attributing some changes to fluctuating climate conditions across seasons.

Dooley remarked that this new research holds promising potential for enhancing renewable energy projects along vital migration paths, particularly in regions like the Great Dividing Range and coastal areas including Bass Strait.

While weather radar can track the number of birds in flight, it cannot determine specific species. To address this, the researchers plan to combine radar data with sightings reported by citizen scientists using birdwatching apps. This dual approach aims to refine their understanding of bird species and their migration routes, which is crucial for protecting threatened species such as the orange-bellied parrot and the critically endangered regent honeyeater. Dooley concluded, “More detailed studies could be vital for safeguarding not just migratory species, but also resident mainland birds facing similar threats.”