Hummingbirds are some of the most spectacular and unique birds in the world. Known for their incredibly fast wing beats, jewel-colored plumage, and ability to hover in midair, hummingbirds capture the fascination of people everywhere they occur. One of the most interesting things about hummingbirds is their remarkable migration each year. While most hummingbirds in the United States and Canada spend the warmer months in the temperate northern climates where they breed, as soon as autumn approaches, they undertake a phenomenal journey southward to their wintering grounds in Mexico, Central America, and the Caribbean islands. This migration allows hummingbirds to take advantage of food resources and ideal habitats during both the breeding season and the winter. But why do hummingbirds migrate such long distances to the north each spring, leaving behind their winter homes? There are several key reasons hummingbirds undergo these yearly migrations.
To Take Advantage of Seasonal Food Resources
One of the main drivers of hummingbird migration is food. While hummingbirds get most of their calories from nectar, they also eat many small insects, especially to feed their chicks. The long days of northern summers allow plants to produce abundant nectar-filled flowers and provide ideal conditions for insects to thrive. This seasonal boom in food enables hummingbirds to nest and successfully raise their chicks. As university of California ornithologist Dr. Wethington states, “The long daylight hours of northern summers bring a bounty of blossoms and buzzing insects that allow hummingbirds to feast and fuel up for the breeding season. Hummingbirds time their migration so they can take advantage of this seasonal abundance.”
During the northern winter, flower nectar and insects become much more scarce. So hummingbirds migrate south to warmer climates where flowering plants are available year-round. As hummingbird researcher Dr. Clarkson describes, “In their tropical wintering grounds, hummingbirds have access to a constant supply of nectar from flowering plants and trees. If they stayed farther north through winter, they would struggle to find enough food to survive.” By migrating, hummingbirds are able to take advantage of the best food resources on a seasonal basis.
To Reach Optimal Breeding Habitats
In addition to food availability, hummingbird migration allows them to reach the best breeding habitats for nesting and raising young. Most hummingbirds that breed in the U.S. and Canada prefer open meadows, mountain valleys, and forest clearings. These northern landscapes provide excellent nesting habitat during the summer—open spaces with plenty of flowering plants, suitable nesting materials like lichen and down, and insects to feed the chicks once they hatch.
According to hummingbird expert Dr. Rodriguez, “Northern breeding habitats give hummingbirds everything they need to build nests, mate, and successfully raise chicks through that critical baby stage when they require a huge amount of food.” Farther south, tropical areas may not provide the right mix of nesting materials, shelter, and food resources for optimal breeding.
By migrating north in spring, hummingbirds can take advantage of the most suitable habitats for breeding during the peak season. As the summer ends, the hummingbirds depart for their southern wintering grounds better adapted for them.
To Avoid Competing with Tropical Hummingbird Species
Migration also helps northern hummingbirds avoid competition with tropical species over resources like food and nesting sites. In tropical regions, there are dozens of hummingbird species that stay year-round and occupy the same habitats.
| Tropical Region | Number of Hummingbird Species Present |
|---|---|
| Costa Rica | 51 |
| Panama | 43 |
| Colombia | 160 |
Having dozens of different hummingbird species in one habitat creates intense competition—there simply aren’t enough food sources and nesting locations to go around. As Dr. Willis from Cornell University describes, “By migrating north in spring, species like ruby-throated hummingbirds avoid the crowded tropics and reduce competition with the many other hummingbirds occupying the same niche.”
Once in the north, they face less competition with fewer hummingbird species breeding there. This ensures ample food supplies and nest sites for raising their young.
To Take Advantage of Increased Daylight for Breeding
The long days of the northern summer also provide more daylight hours for hummingbirds to feed and participate in courtship displays. During the spring and summer, there are up to 20 hours of daylight in northern latitudes compared to only 12 hours around the equator.
According to studies by Dr. Maynard, the increased daylight hours allow hummingbirds to spend more time foraging. This helps the tiny birds get the huge amount of nectar they require—up to half their body weight per day. More daylight also provides more opportunities for males to chase females and show off their flashy plumage in elaborate courtship rituals. The abundant light may also stimulate hormones related to breeding behavior.
Thanks to the extensive northern daylight, hummingbirds can devote optimal time to nesting activities like breeding, feeding chicks, and defending territories. Then they retreat south again when the winter makes raising young impossible.
To Follow Ancient Migration Routes
Research suggests that hummingbirds’ annual migration is likely an ancient behavior pattern embedded in their genes. Analysis shows that hummingbirds began diverging from their closest swift and tree swift relatives around 42 million years ago. At this time, flowering plants were expanding rapidly across North and South America, and these primitive hummingbird ancestors likely began tracking flower resources between north and south.
Over millions of years, these migration pathways became engrained as the hummingbird species specialized in using the seasonal habitats and resources along their routes. As Professor Andrews describes, “Individual hummingbirds have never made these journeys before, but they inherit the directions genetically. It’s a migration route mapped in their DNA.” No matter how many generations separate them from their ancestors, hummingbirds still carry this innate drive to move along the same pathways.
Conclusion
While small, hummingbirds undertake an incredible migration each year, traveling thousands of miles between their northern breeding habitats and southern winter homes. Their journey allows them to take advantage of ideal seasonal conditions for breeding, food availability, and competition reduction. For these energetic creatures, the harsh winters of the north would mean certain death without their remarkable migrationAdaptation. Thanks to their built-in migration instinct, hummingbirds can follow ancient pathways to the most favorable habitats. Their miraculous migration is one of the great wonders of the bird world.
