Fattening up for burning 150,000 calories per day, sleep-flying and other amazing migration facts

Amazing Migration Facts

We all know many birds migrate in the spring and fall – 4 billion birds are headed south over the United States this season.

Some interesting facts about migration include:

Only 2.6 billion return in the spring; the fall migration is larger because young birds born during the summer fly south with their parents.
Some birds, such as Canada geese, migrate during the day and need visual cues to fly in their well-known V formation.
Birds like Broad-winged hawks use thermals to help propel them on their migration south.
Other birds, such as some species of hawks and falcons, use thermal updrafts to convey them on their way, saving valuable energy by coasting over much of their journey.

Some birds burn 150,000 calories per day and even sleep-fly during migration.

Author's summary: Birds migrate in amazing ways, using thermals and visual cues.

Cambridge Day — 2025-10-18