Just like most people, hummingbirds prefer warm weather to chilly winters. For many, heading south in the winter is not a preference but a requirement, because the tiny birds cannot tolerate cold temperatures. They venture back to more northerly backyards in spring or summer. That's usually the optimal time to hang your hummingbird feeders. However, in a few spots on both coasts, hummingbirds hang around all year long.
Hummingbirds are the tiniest birds in the world, but they can migrate thousands of miles every year from breeding grounds in the north to wintering sites in the south. Unlike geese, hummingbirds don't migrate in great "V's" of birds, or in flocks at all. Instead, each hummer migrates on its own, flying low to the ground during daylight hours to profit from any food sources it passes, then sleeping at night.
Figuring out when your backyard hummingbirds are going to head south and when they are going to return to eat at your hummingbird feeders is more than a matter of looking at the calendar. While generally it can be said that hummingbirds fly south in autumn and north in spring, the real routine depends on a variety of factors, including sunlight level changes, decreases in natural food sources and weather patterns. Individual factors for a particular bird include age (mature birds start earlier), sex (males tend to start south a little earlier than females) and the distance the bird has to travel.
Approximate Migration Dates
Generally, the farther north you live and the colder your climate in the winter, the sooner hummingbirds begin to migrate south. Likewise, it will take hummingbirds longer to return to these spots in the spring.
Some species of hummingbirds may leave northern states in July to migrate, but most don't fly south until late August or September. Then, on the reverse trip, hummers may actually leave their wintering spots as early as January to fly north, but they won't arrive in the northern states until mid-May.
One hummer that leaves early is the Rufous hummingbird. It breeds in Alaska and winters in Mexico. To make this long journey, it begins flying its migration route weeks before other hummingbird species are traveling. The ruby-throated hummingbird breeds throughout the eastern half of the country and up into Canada. Those in Canada and other areas of the northern range leave earlier as well. In Washington, hummers arrive in May and depart in October.
On the other hand, Anna's hummingbird, which breeds along the mild areas of Arizona and coastal areas on the West Coast, tends to stay put and not migrate at all. In these areas, hummingbird feeders are a year-round affair.
Putting Out Feeders
If you live in the northern edge of a hummingbird's range, you can take down the feeders in early fall after the birds have headed south. Put them back up in mid-spring, just in case the birds arrive early.
Those in other areas of the United States might consider leaving the feeders out later in fall and putting them out earlier in spring. Hummers will need food as they migrate south, so keeping your feeder available helps those passing through get enough to eat along the way. In Missouri, for example, the hummingbirds usually arrive in late April, but it wouldn't hurt to start hanging the full feeder earlier in the month.
Don't forget to clean out your feeder regularly to keep it healthy for hummers. Fill your feeder with fresh sugar-water every few days. Consider hanging a few if you notice feuding male hummers hanging around your backyard.