Yes, ruby-throated hummingbirds are migrating in the fall months. Ruby-throated hummingbirds are the only breeding hummingbird species in Eastern North America. They spend the spring and summer across Eastern North America and into Southern Canada, but migrate south to Mexico and Central America for the winter.
When do ruby-throated hummingbirds migrate?
Ruby-throated hummingbirds usually start their fall migration in August and September. Some of the first ruby-throats start heading south as early as late July from the most northern parts of their breeding range. The peak of ruby-throated hummingbird migration occurs in mid-September for most of the United States and Southern Canada.
By early October, the vast majority of ruby-throated hummingbirds have left their breeding grounds and are making their way south. Some stragglers may remain through October, especially in the southernmost parts of their breeding range like the Gulf Coast. But by November, essentially all ruby-throated hummingbirds have left for their wintering grounds in Mexico, Central America or the Caribbean.
Fall migration timing by region
Here is an overview of when ruby-throated hummingbirds typically migrate away from different regions:
- Mid to late July: Far northern breeding range like Canada, Michigan, Minnesota, New York
- Mid August: Midwest, Northeast, New England, Mid-Atlantic, Appalachians
- Late August: Mid-Atlantic, Southeast
- Mid September: South along Atlantic Coast, Gulf Coast
- Late September to Early October: Gulf Coast
What is the fall migration route for ruby-throated hummingbirds?
Ruby-throated hummingbirds take different migration routes in the fall depending on their starting location. But they generally follow natural geographical pathways south like major river valleys and coastal plains.
Eastern Routes
Birds breeding in eastern parts of the range such as New England, the Mid-Atlantic and Upper Midwest often migrate south hugging the Appalachian Mountains. Some fly over land across the Eastern United States towards the Gulf. Others follow the Atlantic coastline and islands like the Outer Banks before crossing the Gulf of Mexico.
Central Routes
Birds from breeding grounds in the Midwest often trace the Mississippi River valley south. They follow south through Louisiana and Texas toward Mexico.
Western Routes
Some ruby-throats breeding in central parts of Canada head southwest through the Great Plains into Texas and Mexico. Others from the far western areas of the breeding range migrate through the Southwest United States.
How do ruby-throated hummingbirds know when to migrate?
Ruby-throated hummingbirds migrate in response to changes in day length, not temperature changes. As days get shorter after the summer solstice, hormonal changes trigger hyperphagia – increased appetite to accumulate fat reserves. Shortening days also initiate restlessness and urge to migrate.
Availability of food like nectar may also help signal time to migrate. When flowers and nectar sources start declining in the fall, it may prompt the birds to start migration.
How long is the ruby-throated hummingbird migration?
Ruby-throated hummingbirds may migrate over 1,500 miles between their breeding and wintering grounds. The duration of their migration depends on the distance travelled:
- Northern breeders: 60+ days
- Central breeders: 30 – 60 days
- Southern breeders: 2 weeks – 30 days
The pace of migration also varies, but ruby-throats can travel over 20-40 miles on a single night’s flight. They need stopovers to rest and refuel along their journey, spending a few days to a couple weeks in different locations.
Daily migration pattern
Ruby-throats migrate mainly at night when conditions are cooler and calmer. They fly from 30-40 miles each night. During the day, they rest and feed on nectar and insects to gain energy for the next night’s flight.
Do ruby-throated hummingbirds migrate solo or in flocks?
Ruby-throated hummingbirds mostly migrate individually. They are solitary birds and do not form flocks, even during migration.
However, favorite stopover spots with abundant food sources may temporarily concentrate numbers of migrating ruby-throated hummingbirds. But they do not actively congregate in groups or flocks.
What are the major threats to migrating ruby-throated hummingbirds?
Ruby-throated hummingbirds face many threats during their long fall migration, including:
Lack of stopover habitat
Loss of native flowering plants and nectar sources for refueling due to urbanization, land use changes, and herbicide use.
Extreme weather
Storms, high winds, and cold snaps can force exhausted birds down early or lead to mortality.
Low fuel reserves
Lack of food at stopovers prevents adequate fat storage to continue journey. Hummingbirds have high metabolism and need to continually refuel.
Predators
Predatory birds like falcons feed on hummingbirds during migration. Insectivorous bats and even some jumping spiders also prey on them.
Communication towers and buildings
Migrating hummingbirds can become disoriented by artificial light pollution interfering with navigational cues from stars and moon.
Threat | Impact on Hummingbirds |
---|---|
Lack of stopover habitat | Insufficient food sources to refuel and continue migrating |
Extreme weather | Forced down early, exhaustion, or mortality |
Low fuel reserves | Inability to continue migration due to energy needs |
Predators | Increased mortality during migration journey |
Light pollution | Disorientation and collisions with structures |
Conclusion
In summary, most ruby-throated hummingbirds are indeed migrating in the fall months between August and October. Their migration is an incredible journey fueled by instinct and adaptations that helps them travel hundreds or thousands of miles. This phenomenon connects their breeding and wintering grounds across North America. Supporting their needs along the way through habitat conservation and reducing threats is crucial for maintaining healthy ruby-throated hummingbird populations.