Abstract
Protected areas, Key Biodiversity Areas and other recognised sites for birds are often identified using surveys, count data and other evidence of important breeding, feeding, roosting and staging habitats. However, these site-based assessments generally do not capture how birds move between important sites and across the wider landscape or seascape, leaving the airspace that connects them largely unconsidered and unprotected. This gap is especially important during migration. Although migratory soaring birds travel along broadly demarcated flyways, coastlines, water crossings, straits, ridgelines and mountain passes can funnel large numbers through relatively narrow bottlenecks. These features are often also attractive for wind energy development because of their strong and consistent wind resource, creating potential conflict between migratory movement and development opportunity. Managing this risk is limited by incomplete knowledge of seasonal routes, flight heights, alternative pathways and weather dependent movements.
Satellite and GPS tracking can help fill this gap. When interpreted alongside migration counts, radar, field surveys and expert knowledge, movement data can reveal alternative routes, bottlenecks, staging areas, sea crossings and differences between seasons or age classes. This evidence is particularly valuable before sites are fixed, when avoiding higher-risk areas remains possible, and survey investment can be directed towards the uncertainties most likely to affect feasibility, permitting and finance.