Hummingbirds are captivating birds, known for their iridescent plumage and rapid wingbeats. These small creatures embark on impressive annual migrations, traveling thousands of miles between their wintering grounds and breeding territories. For residents of Iowa, the return of hummingbirds each spring signals the renewal of the season.
The Annual Migration and Iowa Arrival
The primary hummingbird species observed in Iowa is the Ruby-throated Hummingbird. These birds undertake a long journey, migrating from their wintering grounds in Central America, including southern Mexico, Guatemala, Honduras, Nicaragua, and Costa Rica, to their breeding territories in the eastern United States and Canada. Some also winter along the U.S. Gulf Coast. Their northbound migration begins in late February or early March, with males often arriving about two weeks before females to establish breeding territories.
Ruby-throated Hummingbirds arrive in Iowa in mid to late April. While the exact arrival dates can vary each year, mid-April is a good time to anticipate their return. They spend the summer in Iowa, where they mate, nest, and raise their young. These birds exhibit great endurance, with some capable of flying non-stop for up to 500 miles across the Gulf of Mexico.
Factors Influencing Their Return
The timing of hummingbird migration is determined by environmental cues. Changes in daylight length, temperature shifts, and the availability of food sources all play a role in triggering their migratory instincts. As days lengthen in the spring, a hormonal shift prompts them to begin their journey northward.
Warmer winters can lead to earlier departures from their wintering grounds, potentially influencing earlier arrivals in their northern habitats. The presence of early blooming flowers and insect populations along their migration route and in Iowa provides the necessary nectar and protein for their journey and breeding season.
Welcoming Hummingbirds to Your Yard
Creating a welcoming environment can encourage hummingbirds to visit your yard throughout the summer. Setting up hummingbird feeders with a suitable nectar solution is effective. Prepare this by mixing one part refined white sugar with four parts water until the sugar dissolves. It is not necessary to boil the water, but ensure the sugar is fully dissolved, and never use honey, artificial sweeteners, or red dye.
Regular cleaning prevents mold and bacterial growth, which harms birds. Feeders should be emptied and cleaned every few days, or daily in hot weather, using hot water and a brush. For thorough cleaning, use a mild soap, bleach, or vinegar solution, followed by a complete rinse. Additionally, planting native flowers with tubular shapes in bright colors like red, orange, and pink, such as Bee Balm, Cardinal Flower, Trumpet Vine, and Fuchsia, can attract hummingbirds by providing natural nectar sources. Providing water features like misters, drippers, or shallow fountains can also offer hummingbirds a place to bathe and preen.
Preparing for Their Departure
Hummingbirds typically remain in Iowa through the summer for breeding. They begin their southward migration in late summer, usually departing by the end of August or early September. Most hummingbirds will have left Iowa by mid-September, though some individuals may linger until early October if warmer temperatures persist.
Their departure is triggered by the shortening of daylight hours, which signals that it is time to migrate south, rather than a lack of food. It is beneficial to keep feeders available for a couple of weeks after the last sighting to support any late migrants or stragglers passing through from further north. Most Ruby-throated Hummingbirds will migrate to Central America or southern Mexico for the winter.