Natural History Wanderings

ScienceDaily reports

Passerine birds, also known as perching birds, that migrate by night tend to fly faster in spring than they do in autumn to reach their destinations. This seasonal difference in flight speed is especially noticeable among birds that only make short migratory flights, research shows. As short-distance migratory birds, they have the luxury to wait until winds are just right.

Read story at Migrating birds sprint in spring, but take things easy in autumn — ScienceDaily.