Hummingbirds are some of the most fascinating birds. Their ability to hover mid-air and fly backwards sets them apart from other species. Hummingbirds are native to the Americas and there are over 300 different species. While hummingbirds live year-round in the tropics, most hummingbird species that live in North America are migratory birds. This means they travel great distances every year between their summer breeding grounds and winter homes.
When do hummingbirds migrate?
Hummingbirds that live in the United States and Canada migrate south in the fall to escape the cold winter months where food sources are scarce. The exact timing of hummingbird migration varies by species and location, but typically occurs between mid-August and early November. Here is an overview of when common hummingbird species migrate from the United States and Canada:
- Ruby-throated Hummingbird – Most leave the United States by early October
- Rufous Hummingbird – Most leave Canada and the Pacific Northwest by early August
- Allen’s Hummingbird – Most leave coastal California by late September
- Anna’s Hummingbird – Some populations migrate south from Canada and the Pacific Northwest, others are permanent residents
- Calliope Hummingbird – Most leave Canada and the northwestern U.S. by mid-September
The spring migration back north usually happens between late February and early May as the weather warms and food sources become more abundant.
What triggers hummingbird migration?
There are a few key factors that trigger hummingbirds to begin migrating in the fall:
- Decline in food sources – Flowers and nectar-producing plants start dying off after the peak of summer, making it harder for hummingbirds to feed.
- Shortening daylight hours – The days start getting noticeably shorter in the late summer and early fall. This natural decline in daylight hours triggers changes in a hummingbird’s hormones and metabolism to prepare for migration.
- Cooler temperatures – Hummingbirds are small and susceptible to cold temperatures and weather. As northern regions start experiencing cooler weather in the fall, hummingbirds instinctively know to migrate south where it is warmer.
In the spring, the lengthening daylight hours, warmer temperatures, and newly blooming flowers and plants signal to hummingbirds that it’s time to migrate north again.
Where do hummingbirds go in winter?
When hummingbirds migrate for the winter, they fly south to warmer climates where flowering plants and food sources are more abundant. Here are the general wintering grounds of some common hummingbird species that migrate:
- Ruby-throated Hummingbird – Mexico, Central America, Florida
- Rufous Hummingbird – Mexico, Central America
- Allen’s Hummingbird – Coastal California and Mexico
- Anna’s Hummingbird – Pacific coast from California to Baja Mexico
- Calliope Hummingbird – Mexico
Some key areas where hummingbirds overwinter include:
- Southern Arizona and Texas
- Southern Florida
- Pacific coastline from California to Mexico
- Mexico
- Central America – Costa Rica, Panama, Guatemala, Belize
Hummingbirds from farther north migrate the longest distances. For example, Rufous Hummingbirds that breed in Alaska may fly over 3,000 miles to reach their winter grounds in Mexico!
How do hummingbirds know when and where to migrate?
Hummingbirds have an incredible inborn ability to navigate to specific wintering sites each year despite never having been there before. They likely use a combination of the following cues:
- Instinct – Young hummingbirds making their first migration follow experienced adults and rely on an innate sense of navigation.
- Celestial cues – Hummingbirds use the location of the setting sun and patterns of stars to determine direction.
- Earth’s magnetic field – Hummingbirds can detect the electromagnetic field around the planet to help orient themselves.
- Landscape features – Mountain ranges, coastlines, and rivers may provide landmarks during migration.
- Sense of smell – Odors and scents from food sources and other birds may draw hummingbirds along established migration routes.
How long does the migration take?
Hummingbirds migrate relatively quickly considering their small size, but migration is still an arduous journey. Here are some estimates for how long it takes certain species to complete their fall and spring migrations:
- Ruby-throated Hummingbird – Up to 2 weeks each way
- Rufous Hummingbird – 4-6 weeks each way
- Allen’s Hummingbird – About 2 weeks each way
- Calliope Hummingbird – Up to 3 weeks each way
The duration depends on factors like the distance traveled, weather, food/fuel availability along the route, and how often the birds stop to rest. The longest migrations, like those of Rufous Hummingbirds, can take months to complete as the birds travel in a meandering path with many stops along the way.
How far do hummingbirds travel during migration?
Migration distances vary widely among hummingbird species and populations. Some examples of one-way migration distances:
- Ruby-throated Hummingbird – Between 1,500 – 2,000 miles from breeding areas as far north as Canada down to southern Mexico and Panama
- Rufous Hummingbird – Up to 3,000 miles from Alaska to Mexico
- Allen’s Hummingbird – Around 1,000 miles from the Pacific Northwest to Mexico
- Costa’s Hummingbird – Up to 2,000 miles from breeding areas in the southwest U.S. and Mexico down to Costa Rica and Panama
As a general rule, hummingbirds that breed farther north migrate the longest distances. Incredibly, some individual hummingbirds may log over 10,000 miles of flying over the course of a year when both fall and spring migration distances are accounted for!
How fast and high do hummingbirds fly during migration?
Hummingbirds are capable of flying long distances at fast speeds when migrating. Here are some key facts about how hummingbirds fly during their biannual migrations:
- Speed – 20-40+ mph; faster with tailwinds
- Altitude – Typically lower during migration compared to normal flight; 1,000 – 4,000 feet
- Distance – Fly approximately 300-600 miles at a time, stopping to rest and refuel in between
- Optimal conditions – Prefer flying low across land on calm, warm days with tailwinds
Flying for hours or days over open water, at high altitudes, or in strong headwinds slows down their progress. But hummingbirds are built for sustained hovering and can fly hundreds of miles nonstop when conditions are right.
What do hummingbirds eat during migration?
Hummingbirds get most of their nutrition from nectar and small insects like gnats, fruit flies, aphids, and spiders. During migration, they seek out food in the following places:
- Backyard feeders – Hummingbirds use feeders in backyards as convenient refueling stations. Keep feeders up through early fall and stock them with nectar (1 part sugar to 4 parts water).
- Flowering plants – Native and cultivated flowers that bloom late into fall provide essential energy sources. Some late bloomers hummingbirds visit during migration are salvia, zinnias, trumpet vine, butterfly bush, and cigar plants.
- Trees and sap – Hummingbirds will occasionally sip tree sap or sap wells created by sapsucker woodpeckers which provide sugar and calories.
- Insects – Hummingbirds will opportunistically eat small insects which provide protein for their strenuous flight.
Availability of food and foraging stops dictates migration routes and timing. Hummingbirds need frequent access to high energy nectar and sugar sources to sustain their demanding long-distance travels.
Why do hummingbirds migrate?
Hummingbirds migrate for a few key reasons:
- Food availability – The main trigger is lack of flower nectar and insect food sources in northern regions in the winter.
- Cold temperatures – Hummingbirds are at risk in below freezing temperatures and can easily succumb to hypothermia.
- Breeding – Migration allows hummingbirds to breed during the peak warm summer months up north.
- Seasonal abundance – Migration follows available food and allows hummingbirds to take advantage of seasonal peaks in food in different regions.
Without migration, most hummingbird species would not be able to survive cold northern winters or successfully breed and raise chicks. Their small size and extreme metabolic demands necessitate migration to warmer climates each winter.
Threats and dangers hummingbirds face during migration
Hummingbirds face many threats and obstacles on their migration journeys each fall and spring. Some of the major hazards include:
- Lack of food/habitat – Migration routes with insufficient flowers, blossoms, and nectar sources can leave birds starving or weakened.
- Extreme weather – Storms, high winds, fog, precipitation, and temperature swings interfere with optimal migration conditions.
- Predators – Hawks, falcons, and other birds of prey pose a constant threat during migration.
- Building collisions – Windows, towers, wind turbines, and other structures claim many migrant hummingbird lives each year.
- Exhaustion – The journey taxes hummingbirds’ energy reserves and some simply run out of steam.
Research estimates that 40-70% of hummingbirds die within their first year, most during their initial fall migration. Expanding suitable habitat along migration routes and providing artificial food sources may help more hummingbirds successfully complete these incredible journeys.
Interesting hummingbird migration facts
- Ruby-throated Hummingbirds travel across the Gulf of Mexico 500 miles nonstop – the longest known open water crossing of any bird relative to its body size.
- Black-chinned Hummingbirds have one of the latest fall migration start times, with most leaving their California summer grounds in October.
- Rufous Hummingbirds migrating down the Pacific Coast form massive flocks up to hundreds of thousands of birds along their route.
- Hummingbirds migrate like other birds in the daytime and spend nights resting. They can enter torpor, a mini-hibernation to conserve energy overnight.
- The age and sex of hummingbirds may influence migration timing. Adult males tend to migrate first in spring, younger birds migrate later.
- Hummingbirds appear capable of navigating using true navigation – finding their way even when blown off course – based on a mental map and compass senses.
- Climate change may be altering hummingbird migration timing. Some species now arriving farther north earlier as winters warm.
Conclusion
Hummingbird migration is an awe-inspiring phenomenon. The tiny birds undertake journeys of thousands of miles solely through their innate navigational abilities. Providing food, habitat, and safe passage along their migration routes gives these resilient migrants a better chance of successfully perpetuating this extraordinary process. Understanding when, where, how, and why hummingbirds migrate allows us to support these colorful seasonal visitors on their incredible intercontinental journeys.
