The estimated number of birds in flight across the continental United States. Mean is calculated as the average number of birds aloft across 10-minute continental snapshots assigned to a night from dusk through dawn (~86 snapshots per night in these data). Peak is the largest single continental 10-minute snapshot within an individual night. Units: birds.
| Night of year | Mean birds aloft (nightly) |
|---|
Migration traffic (MT) i is calculated by time-integration of migration traffic rates (MTR) from March 1 through June 15: MT = ∫ MTR dt. MT gives the estimated number of birds that passed per kilometer perpendicular to the migratory direction over the full spring period, aggregated by state. It represents cumulative passage and supports comparisons among states. Units: birds/km.
| Rank | State | birds / km |
|---|
Daily migration traffic is calculated independently for every raster pixel as Σ(MTR × interval_hours) for the labeled local civil night, from dusk through dawn. Use the player to inspect nightly totals across spring 2026. Units: birds/km.
Colors use a logarithmic scale. Transparent areas indicate little detected migration; brighter colors indicate greater nightly traffic.