The Radar Network for Biodiversity Monitoring: Movement-Trait Indicators from Airborne Wildlife

Monitoring animal movement at meaningful spatial and temporal scales remains a major bottleneck for biodiversity assessment. Many policy frameworks rely on sparse counts, opportunistic observations, or delayed reporting pipelines that struggle to capture rapid ecological change. We present an emerging approach that uses a distributed network of high-resolution vertical-looking radars to measure the movement of airborne animals in near real time. These sensors record continuous trajectories and motion traits of birds, bats, and insects with no tagging effort, providing an integrated view of aerial biodiversity across taxa.

Even a modest number of radar stations can resolve large-scale spatiotemporal patterns. By combining radar-derived movement traits with environmental and landscape data, we can quantify migration fronts, seasonal traffic rates, diel movement strategies, and longer-term behavioural shifts. Preliminary analyses show strong correlations in movement intensity between radar sites separated by tens to hundreds of kilometres, indicating that the system captures coherent regional-scale dynamics rather than isolated local signals. This opens the door to scalable, transboundary indicators of aerial vertebrate and invertebrate activity.

The potential applications are broad. Radar-based movement metrics support early warning systems for agricultural pests or declining pollinators, inform bat and bird collision risk assessments at wind energy facilities, contribute data about bird strike risks for aviation, provide near real-time indicators relevant to zoonotic disease surveillance, and enable long-term tracking of phenological and distributional change under climate pressure. Because the data stream is continuous and harmonised across sites, it can complement existing biodiversity reporting frameworks by supplying movement traits that are consistent, comparable, and policy-relevant.

We show how vertically oriented radar measurements can be distilled into indicators such as traffic rates, diel timing metrics, flight height distributions, and migration intensity indices. These reveal coherent spatial and temporal structure across sites and demonstrate how a radar network resolves regional patterns in aerial activity with minimal configuration. By capturing these dynamics at scale and in near real time, radar networks provide a robust basis for tracking shifts in aerial biodiversity and informing conservation decisions that depend on timely movement information.