5 min readAs summer fades into fall, the tiny hummingbirds you’ve been watching in your garden are getting ready for a journey. But if you’ve been keeping a feeder up, you may wonder whether it will interfere with these birds' migration.
Incredibly, hummers migrate solo—and where they go depends on the species and where they live. Some species have much longer trips than others, flying thousands of miles across the Gulf's open water.
“For ruby-throated hummingbirds, which are widespread across the eastern and central U.S., most migrate to Mexico and Central America for the winter,” says Chad Witko, a specialist in avian biology with the National Audubon Society.
Some birds migrate to the southern and coastal U.S. In places such as Louisiana and the Gulf Coast, you’ll find several species, including some from the West. And some species, such as Anna’s hummingbird, remain year-round in parts of the western U.S., says Witko.
Ahead, here’s what else you should know about migration and whether keeping up your feeder will impact these little beauties.
Why Do Hummingbirds Migrate?
These teeny birds need lots of nourishment they can’t find in winter in northern climates.
“Hummingbirds eat mainly flower nectar and insects,” says Holly Grant, project assistant for NestWatch at Cornell Lab of Ornithology. “They actually spend most of their year in southern tropical areas to take advantage of the plentiful food supplies, and migrate north simply to breed.”
Because these birds are more territorial in nesting season and have larger territories they defend at this time, it makes more sense to go where there’s plenty of room to raise a family. “So, dispersing to the northern areas where there’s both space and ample food to raise young is ideal,” says Grant.
What Triggers Hummingbirds to Migrate?
Several factors affect when a hummingbird actually begins its journey.
“There are a lot of migratory variations in hummingbirds, from very short migrations to very long ones,” says Gregor Yanega, conservation program director at the California Central Coast Joint Venture for American Bird Conservancy.
One factor impacting hummingbird migration is the number of daylight hours. “Day length triggers hormonal chain reactions that initiate intense periods of feeding and migratory behaviors,” says Yanega. “However, depending on the species, sex, and age class of the hummingbird, their response to these cues will differ.”
For example, a male rufous hummingbird will feed until it gains enough mass and then begin its migration south, whereas a female rufous hummingbird’s migratory cues are delayed by reproductive hormones. “If a late brood is still being tended to, she will not prepare for migration until after they have fledged,” says Yanega. Last to leave for the year are the first-year birds, who take longer to find food and put on weight prior to their departure.
Some species follow the timing of flowers. “Populations from northern latitudes are nearly synchronous with the peak flowering of jewelweed (Impatiens capensis), so it’s possible that is an important food resource during migration,” says Grant. “Birds from more southerly latitudes don’t have this relationship with jewelweed, but there are other flowers like trumpet creeper (Campsis radicans) and Turk's cap (Malvaviscus arboreus var. drummondii) that are major nectar sources along the Gulf coast.”
In addition, just like you wouldn’t leave on a long road trip if a storm is forecast, the birds may adjust accordingly. “Weather can be especially important during migration, as hummingbirds may alter their movements in response to favorable or unfavorable conditions,” says Witko.
Will Leaving Your Feeder Up Interfere with Migration?
The good news is that you aren’t doing any harm to the hummingbirds by keeping your feeder up.
“Keeping a hummingbird feeder available does not delay migration or prevent hummingbirds from leaving,” says Witko. “The same is true for many seed feeders and other birds. A feeder is no different from a natural food source in that it provides the energy to migrate, but it does not override those migration cues. In fact, reliable food can be especially helpful for birds preparing for migration or making their way south.”
The bottom line is the birds know what to do! “One of the biggest misconceptions is that feeders somehow make hummingbirds dependent on people or prevent them from migrating,” says Witko. “They don’t. Hummingbirds are wild animals with highly developed migratory behaviors, and a feeder is simply a supplemental food source. They’ll use feeders in much the same way they use other food sources, incorporating them into the rotation of what’s available to them.”
Should You Leave Hummingbird Feeders Up All Year?
You don’t have to take a feeder down based on a particular date on the calendar. “Keep it available as long as hummingbirds are using it,” says Witko. “Once you’re confident that the birds have moved on, you can take it down. Some folks like to keep it up for two weeks after the last visible hummingbird comes through.” In parts of the southern and western U.S., hummingbirds can be present throughout the winter, so feeders can be maintained year-round.
In the rest of the country, leaving feeders up well into fall also may be helpful to exhausted birds that are flying down from populations that breed farther north and need an extra energy boost to make it to their destination, says Grant.
Essentially, your feeder can be a rest stop of sorts. “Species that migrate really long distances, such as Ruby-throated hummingbirds and Rufous hummingbirds, will stop midway—at what we call stopover sites—for as much as a week at a time,” says Yanega. “Birds will forage for nectar and insects to rebuild fat stores and lost muscle mass. Insects are an important part of a hummingbird’s diet, especially during migration, as the proteins needed to rebuild muscle cannot be obtained from nectar.”
If you do keep feeders up, clean them regularly; all you need to use is hot water and a bottle brush to scrub out any residue. Change the nectar every few days, especially in hot weather, and clean the feeder whenever you change the nectar, says Witko.
You also can support hummers by planting native plants (find what’s best for your region here). “Feeders are only part of the picture,” says Witko. “Hummingbirds need natural flowers for nectar and insects for protein and other nutrients, especially during the breeding season and migration. Providing native flowering plants and avoiding pesticides can help create habitat that supports hummingbirds throughout their annual cycle.”
