Migration Route: Over Land — or Water?

What happens when migrating Ruby-throated Hummingbirds reach the Gulf of Mexico? Most rubythroats fly nonstop 500 miles or more across the water to Mexico and other Central American countries. Some rubythroats fly over land, following the coastline to reach their wintering grounds.

Ruby-throated hummingbird migration map with sample distances traveled.
Map: NASA

It's a mystery how individual birds decide to migrate over land or water. Following a land route lets them stop to rest and refuel, but they can't count on easy food all along the way. Flying over water is shorter, but they can't rest or refuel and may meet dangerous conditions in hurricane season. Ruby-throated hummingbirds fly at night for most of their journey across the Gulf of Mexico.

Hummingbird amongblossoms
Photo: Ann Fitzgerald

Fall Migration Q & A:

  • Do hummingbirds follow the same route fall and spring? Dr. David Aborn, ornithologist, tells us: "I am not aware of any hummingbirds that exhibit what is known as a loop migration — where a species flies one route during fall migration, and a different route during the spring."
  • Do all go south? Most hummingbirds that breed in the U.S. and Canada winter south of the U.S./Mexico border. However, scientists are still making discoveries. Recent research by field ornithologists has recorded individual hummingbirds of a dozen different species that spend winter in the US.

  • Do they take the same route every year? Banding has shown that migrating hummingbirds have great fidelity to their migration routes. Amazingly, banders have reported annual encounters with banded birds on the same day each year!
  • How do they know the way? The exact guidance system is unknown, but it seems mainly instinctive. Hummingbirds migrate alone, not as a group, so they can't learn routes from one another. The babies seem to know where to go even though they've never been there before. Young hummers migrate along the same routes and winter in the same places their ancestors have. These wondrous tiny birds leave scientists much to discover!