MIGRATION: The Rufous Hummingbird has the longest migration of any hummingbird, more than 5,000 miles a year. It flies from central Mexico to Alaska and back again. Hummingbirds migrate, not in flocks, but each one entirely alone. Males leave first followed by females several weeks later. On the south-bound journey the young leave last, flying alone on their first migration with no adult to guide them. In its migration to Mexico, the tiny Ruby-throated hummingbird, almost unbelievably, tackles the sea crossing directly. Its cruising speed is about 27 miles an hour, so if conditions are favorable, it can make the transit, non-stop, in around 18 hours. But the passage is a formidable one and it taxes the hummingbird to the limit of it endurance. A head wind, even a mild one, may hamper it so severely that it will never reach the far shore and perish at sea. Ref:
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