Hummingbirds that breed in Iowa migrate south in the fall to spend the winter in warmer climates. The two main species of hummingbirds found in Iowa are the Ruby-throated Hummingbird and the Rufous Hummingbird.
Ruby-throated Hummingbird
The Ruby-throated Hummingbird is the most common and widespread hummingbird species in eastern North America. These tiny birds breed throughout most of the eastern United States and Canada during the summer months. In the fall, Ruby-throats living east of the Mississippi River migrate down through Florida and into Central America or Mexico for the winter.
Banding and tracking studies have shown that Ruby-throated Hummingbirds that breed in Iowa take different migration routes depending on their breeding location in the state:
- Birds in eastern Iowa tend to migrate southeast through southern Illinois, Indiana, Kentucky and Tennessee before reaching the Gulf Coast.
- Birds in central Iowa migrate almost directly south through Missouri, Arkansas, and Louisiana to reach the Gulf of Mexico.
- Birds in western Iowa migrate southwest through Kansas, Oklahoma, and Texas before traveling south into Mexico.
Their wintering grounds are concentrated along the Gulf Coast region from southern Texas to the Florida panhandle, though some individuals may winter as far south as central Mexico or Panama.
Rufous Hummingbird
The Rufous Hummingbird is a western species that has expanded its breeding range eastward in recent decades. Rufous Hummingbirds nest in increasing numbers in the northwestern part of Iowa, though they are still uncommon in the eastern part of the state.
Rufous Hummingbirds take a remarkably different migration route compared to Ruby-throats. In the fall, Rufous Hummingbirds living in Iowa migrate west along the Great Plains through Colorado and New Mexico. From there, they travel south through Arizona and into Mexico for the winter.
Their winter range is concentrated along Mexico’s Pacific coastline, though some birds may go as far south as Guatemala and El Salvador. Band recoveries show that Rufous Hummingbirds breeding in Iowa have wintered as far south as Oaxaca in southern Mexico.
Timing of Migration
Both Ruby-throated and Rufous hummingbirds usually leave Iowa by late September or early October. The timing of their migration south depends on the weather. Colder temperatures and fewer flowers trigger the birds to begin migrating. Adult male hummingbirds tend to migrate first, followed by females and young birds.
southward migration occurs over a period of 6-8 weeks for most individuals. Some late-nesting hummingbirds, especially young birds, may linger in Iowa into late October or early November if flower or feeder resources remain available.
Spring Migration
In spring, Ruby-throated Hummingbirds first arrive back in Iowa in early April, though most return in mid to late April. Rufous Hummingbirds return later, usually in May. The timing of spring migration is mainly dependent on the abundance of flowers and insects along their migratory route.
Males tend to arrive first on the breeding grounds, followed by females 1-2 weeks later. Upon arrival, hummingbirds quickly establish breeding territories and begin courtship displays to attract mates.
Migration Strategies
Hummingbirds make their long migrations remarkably fast despite their very small body size. Here are some key facts about their migration strategies:
- They can fly up to 25 miles per hour for short bursts.
- They flap their wings up to 70 times per second!
- They normally travel 100-400 miles at a time, stopping to rest and refuel.
- Some Rufous Hummingbirds may migrate 2,000-3,000 miles one way.
- Most hummingbirds migrate alone, not in flocks.
- They feed heavily on nectar and insects to store up fat reserves for the journey.
- They are able to orient themselves using the earth’s magnetic fields.
With these remarkable abilities, a tiny hummingbird weighing only a few grams can complete one of the most incredible migration journeys in the animal kingdom.
Threats During Migration
Hummingbirds face many threats during their fall and spring migrations, including:
- Lack of food sources along migration routes
- Inclement weather such as storms, high winds, or cold temperatures
- Predators such as hawks, cats, and other birds
- Collisions with buildings, towers, vehicles, or other structures
- Habitat loss reducing available resting and refueling spots
Hummingbirds require habitats rich in flowers and insects to successfully complete their arduous journeys. Conservation of natural environments along migration flyways is crucial to supporting their migration needs.
How to Support Migrating Hummingbirds
Here are some tips for Iowa residents to help support migrating hummingbirds:
- Plant native wildflowers and shrubs that bloom late summer through fall.
- Leave seed heads and stems of flowers for birds to forage on.
- Provide nectar feeders as supplemental food sources.
- Avoid pesticide use so feeders don’t become contaminated.
- Position feeders close to trees or shrubs where birds can rest and shelter.
- Keep feeders clean to prevent spread of diseases.
Even small actions by individual homeowners can make a difference for hummingbirds stopping through on migration. Community efforts to protect natural areas and create native plant corridors also greatly benefit migrating hummingbird populations.
Conclusion
Iowa’s breeding hummingbirds, like Ruby-throated and Rufous Hummingbirds, migrate hundreds or thousands of miles in the fall to reach their warmer wintering grounds. Ruby-throats head south to the Gulf Coast and Mexico, while Rufous Hummingbirds migrate west to the Pacific Coast. Providing stopover habitat with late-blooming flowers and feeders can help support these tiny birds on their incredible journeys. Understanding hummingbird migration patterns and threats enables Iowans to better protect these special migrants that grace our landscapes each summer.
