As fall approaches in the Northern Hemisphere, many bird species begin their annual migration south to warmer climates for the winter. Hummingbirds are one of the most iconic migratory birds, with their tiny bodies and whirring wings carrying them on epic journeys across North America. So when do these nectar-loving birds start heading south? Here’s a quick look at what triggers hummingbird migration and exactly when they take off.
What causes hummingbirds to migrate?
Hummingbirds migrate for a few key reasons:
- Food availability – Hummingbirds depend on nectar from flowers for food. As flowers begin to die off with frosts in late summer and autumn, food resources become scarce in their breeding grounds, driving the birds south.
- Cold temperatures – With their tiny bodies and high metabolism, hummingbirds are vulnerable to cold temperatures and can easily become hypothermic. Migrating allows them to avoid frigid northern winters.
- Breeding – Some hummingbird species migrate south to take advantage of optimal breeding conditions and food supplies.
- Day length – Changes in day length may trigger hormonal changes that stimulate the migratory instinct.
By migrating south, hummingbirds can find the food and warm temperatures they need to survive until northern flowers bloom again in spring.
When does hummingbird migration begin?
Most hummingbirds in the United States and southern Canada begin migrating south in August or September. However, exact migration timing can vary by species and depend on a few factors:
- Food availability – Hummingbirds may delay migration if late-blooming flowers are still providing ample food. Once food becomes scarce, they’ll depart.
- Weather – The arrival of cold snaps and frosts will quickly trigger migration.
- Age – Adult hummingbirds tend to migrate first, followed by juveniles.
- Species – Some hummingbird species migrate earlier than others. Anna’s hummingbirds that breed along the Pacific Coast may linger well into October or November.
Here is a table showing the typical migration period for common hummingbird species breeding in the U.S. and Canada:
Species | Migration Period |
---|---|
Ruby-throated Hummingbird | August – September |
Rufous Hummingbird | July – September |
Allen’s Hummingbird | July – September |
Anna’s Hummingbird | September – November |
Broad-tailed Hummingbird | July – September |
Calliope Hummingbird | August – September |
Keep an eye out for increasing hummingbird activity at your feeders and in flowering gardens in mid to late summer. This frenzy of feeding, known as hyperphagia, indicates the birds are bulking up for their long migration ahead.
What routes do hummingbirds take?
The main migration routes hummingbirds follow include:
- Atlantic Flyway – Ruby-throated hummingbirds breeding in eastern North America fly south across the western Atlantic to Mexico, Central America, and northern South America.
- Mississippi Flyway – Rufous and calliope hummingbirds use this inland route along the Mississippi River corridor.
- Central Flyway – Broad-tailed, black-chinned and other western species follow this central route through the Rocky Mountains into Mexico.
- Pacific Flyway – Anna’s, Allen’s, Costa’s and rufous hummingbirds follow the west coast into Mexico and Central America.
Some hummingbirds bypass the tropics altogether and spend the winter in the southern U.S. Hotspots include southeastern Arizona, southern Texas, and along the Gulf Coast where flowers and feeders provide wintertime nutrition.
How far do hummingbirds migrate?
Considering their tiny size, hummingbirds make some of the most epic migrations in the animal kingdom. A few astounding examples include:
- Ruby-throated hummingbirds may log up to 2,000 miles traveling between Canada and Central America.
- Rufous hummingbirds breed in Alaska and migrate an incredible 3,000 miles to Mexico for winter.
- Tiny calliope hummingbirds weighing just 2-3 grams brave 600 mile journeys across the Rocky Mountains.
- Some ruby-throated hummingbirds have been tracked flying nonstop for over 500 miles across the Gulf of Mexico.
The following table summarizes the approximate one-way migration distances covered by some common northern hummingbird species:
Species | One-way Migration Distance |
---|---|
Ruby-throated Hummingbird | 1,500 – 2,000 miles |
Rufous Hummingbird | up to 3,000 miles |
Allen’s Hummingbird | 1,000 miles |
Anna’s Hummingbird | 500 miles |
Broad-tailed Hummingbird | 1,000 – 2,000 miles |
Calliope Hummingbird | up to 600 miles |
Researchers continue to be amazed at the tenacity and endurance displayed by hummingbirds during their biannual odysseys between their northern breeding and southern wintering grounds.
How long does the migration take?
One-way migration can take hummingbirds between a few weeks up to a couple months depending on factors like:
- Distance – Longer migrations obviously take more time to complete.
- Weather – Hummingbirds avoid flying over water during storms and may wait out inclement weather.
- Wind patterns – Tailwinds boost migration speed while headwinds slow progress.
- Fueling stops – Hummingbirds break up their journey by stopping to feed, rest and refuel, extending travel time.
- Age and sex – Adult males tend to migrate faster than juveniles and females.
As an example, here are estimated one-way migration durations for a few hummingbird species:
Species | Duration of One-way Migration |
---|---|
Ruby-throated Hummingbird | 5-7 weeks |
Rufous Hummingbird | 6-8 weeks |
Allen’s Hummingbird | 2-3 weeks |
Broad-tailed Hummingbird | 3-5 weeks |
By traveling in short bursts and resting/refueling in between, hummingbirds are able to complete their thousand mile migrations over the course of weeks or months despite their tiny size.
How can you help migrating hummingbirds?
Here are a few tips for supporting hummingbirds as they pass through your area on migration:
- Keep feeders clean, filled and available into fall – Migrating hummingbirds depend on sugar sources.
- Provide fresh nectar regularly as it spoils quickly in warm weather.
- Plant autumn-blooming flowers and pollinator gardens to give energy.
- Avoid pesticides which can poison birds stopping to refuel.
- Set up a mister for birds to bathe and cool off.
- Report banded birds to research projects like hummingbirds.net.
With a little planning, you can turn your yard into a much-needed migratory rest stop for hummingbirds fueling up for their incredible journeys.
Conclusion
Hummingbirds captivate us with their diminutive size and aerial skills. These tiny travelers also complete some of the most astonishing marathon migrations in the animal kingdom. By providing habitat and stopover support along their routes, backyard birders and gardening enthusiasts can directly aid hummingbirds as they traverse thousands of miles between their breeding and wintering grounds. Pay attention for the arrival of migrants at your feeders in late summer and early fall, then get ready to welcome them back next spring.