数以百万计的迁徙鸟类夜间飞越内布拉斯加州和爱荷华州上空,标志着春季迁徙达到高峰。 Millions of migrating birds fly over Nebraska and Iowa overnight, marking a peak in spring migration.

周一和周二深夜时分,预计约有3.97亿鸟将在内布拉斯加州和爱荷华州上空移徙。 Approximately 397 million birds are expected to migrate over Nebraska and Iowa during late-night hours on Monday and Tuesday. NexRad天气雷达探测到这些高海拔的羊群,它们太高,无法裸眼观察。 NexRad weather radar detects these high-altitude flocks, which are too high for naked-eye visibility. 鸟儿白天休息和进食,有些在夏季留在该地区,而另一些则继续向北。 The birds rest and feed during the day, with some staying in the region for the summer while others continue northward. 这一事件是今年记录的最大春季迁徙之一。 This event marks one of the largest spring migrations recorded this year.