source: Journey North
Track Hummingbird Migration
Fall Migration Begins Soon Fewer hours of daylight trigger hormonal changes that cause an urge to fuel up and fly south. Most hummingbirds that breed in the U.S. and Canada winter in Mexico and Central America. Recent studies also indicate that hummingbirds of a dozen different species spend winter in the US. along the Gulf coast and into Georgia, Florida, and the Carolinas. Many questions remain. Help scientists, researchers and land managers answer pressing questions by continue to submit your hummingbird observations this fall.
Eating Dawn to Dusk Hummingbirds use a lot of energy — darting among flowers, hovering at feeders, and flying long distances. They burn energy so fast that they need to eat 1.5 to 3 times their weight in food each day. If you live in the northern latitudes, your backyard hummingbirds will leave while nectar-rich flowers are still in bloom and feeders are full.
Watch your hummingbirds go on a feeding frenzy before leaving their breeding grounds. They will feed often and intensely for days in a state called hyperphagia. Hummingbirds start feeding as early as forty-five minutes before sunrise and keep eating until dusk. They balance their diet with insects and spiders — necessary sources of protein. Hummingbirds will double their weight as they prepare to fly hundreds or even thousands of miles. To gather enough nectar to meet their high energy needs, hummingbirds must visit hundreds of flowers every day. One hummer can visit as many as two hundred flowers in fifteen minutes!
The Migration Pathway
Hummingbirds must find blooming flowers all along the migration pathway. They travel while their food supply is readily available — before flowers go out of bloom or are damaged by frost. This is why hummingbirds are among the first birds to migrate in the fall.
Hummingbird migration is a stop and go journey. 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. The exact guidance system is unknown, but it seems mainly instinctive.
Adult male hummingbirds are the first to leave breeding ranges. Adult females are the next, followed shortly by juveniles. Some males leave as early as July and August, but most hummingbirds depart towards the end of August and beginning of September.
By leaving earlier than the females and immature birds, the males won’t be competing for fading fall blossoms and other food sources. Newly-fledged birds need the time to mature and gain fat reserves before flying off on their first migration south. More food will also be available along the migration trail when hummers leave at different times.
Hummingbirds migrate alone, not as a group, so they do not necessarily learn routes from one another. The juvenile hummingbirds migrate along the same routes and winter in the same places their ancestors have. These wondrous tiny birds leave researchers much to discover!
Report and follow hummingbird migration:
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