Interannual consistency of migration phenology is season- and breeding region-specific in North American Golden Eagles

Avian migrants can adjust the time they depart for migration and arrive at their destination (i.e. phenology) based on environmental conditions, the period of the annual cycle, and the distance of migration. Our study shows that interannual consistency (an indicator of the strength of adjustments) in migration schedule of Golden Eagles (Aquila chrysaetos) in North America was greatest in boreal spring migration and the breeding regions of eastern Canada, suggesting that migration schedule is partly environmentally driven. Using multi-year GPS tracks of 83 adults breeding in three spatially distant regions (Alaska, northeast Canada, and southeast Canada), we quantified the interannual consistency of migration timing with variations within individuals tracked across multiple years and among-individuals and repeatability (r) of migration schedule, duration, and wintering latitude by breeding regions and seasons. By comparing regions and seasons, we found that consistency was highest (r &gt...