Hummingbird Migration in Winter

By Rose Davis, Milwaukee, Wisconsin

For Bill Hilton Jr., winter is one of the most exciting times to watch hummingbirds.

Bill is an educator-naturalist at Hilton Pond Center in York, South Carolina and has been banding hummingbirds for more than 20 years.

"Hummingbirds are fascinating creatures that break all the rules," Bill says. "They hover, fly backward and build their nests from spiderwebs and lichens. And they're only the size of your thumb!"

Bill's main focus traditionally has been on ruby-throated hummingbirds, which breed in the eastern United States. But recently, he started noticing an increase of vagrants in his area during winter. Vagrants are hummingbirds that fly out of their normal range, and Bill has seen more than 40 in his area in the last 6 years alone.

"There have been far more sightings of winter vagrant hummingbirds in the eastern United States in the last 20 years. Most of them are rufous, which breed in the northwestern United States," Bill says.

Flying on Their Own Terms

Though all hummingbird species have a different migration pattern, most migrate to South America once the days start getting shorter and the weather begins to change. The Anna's hummingbird is the usual exception to this rule, as you can find it year-round on the California coast.

Most other hummingbirds still migrate to South America, but as Bill and other birders are finding, there has been a steady increase of these fliers showing up in the United States during winter, especially along the warmer coastal areas.

"Vagrant birds are intriguing because they, too, are breaking rules-or at least not doing what we humans expect of them with regard to migration," Bill says. "It's entirely possible studying these birds will tell us something about habitat destruction, climate change or range expansion."

Breaking Traditions

Bill believes that several factors may play a part in the increase in hummingbird sightings during winter.

"The two main reasons are that there are more feeders overall, and more people are leaving them up past the traditional Labor Day take-down time," he says.

Some people worry about leaving their feeders up past Labor Day because they think the hummingbirds won't migrate. This isn't the case, however. Hummingbird migration is stimulated by the photoperiod. That means when daylight gets shorter, the birds' instincts tell them to head south.

Bill actually recommends that people leave their feeders up most of the year if they want to attract vagrant hummingbirds. And while it might seem surprising, Bill says the birds are capable of spending winter in the U.S.

Tracking Vagrants

"People have the impression that hummingbirds are tiny, fragile birds, but they aren't fragile at all," Bill says.

"Some species, like the ruby-throated, can't handle the cold winter weather, but others have no problem surviving." While Bill continues his research on both ruby-throated and vagrant hummingbirds, his favorite part of the job is sharing his findings with others.

"There's no sense in learning all this neat stuff unless I get to share it with other people all over the world," Bill says.

That's why he keeps a Web site where he posts his findings and encourages people to do the same. And with the continuing reappearance of these birds each winter, Bill always has something to look forward to and share during these cold months.

Bill's Tips for Attracting Hummingbirds in Winter

If you live in an area with mild winters, try attracting vagrant hummingbirds by leaving your sugar-water feeder up. If you do this, it's important that you keep the sugar water in the feeder fresh and unfrozen.

To keep the sugar water from freezing, you can place a heating lamp above or below the feeder or change the mixture in the feeder throughout the day. Bringing the feeder indoors every night will also help prevent freezing.

The hummingbirds still can get the fats and proteins they need in the winter from the few bugs they find, but sugar-water feeders will enhance their chances of survival.