Hummingbirds, with their iridescent plumage and rapid wingbeats, undertake incredible annual migrations spanning thousands of miles, a testament to their endurance. Witnessing their return each spring signals the change of seasons. Their migratory patterns are a complex interplay of instinct, environmental cues, and the search for optimal conditions.
Unraveling Their Return
Hummingbirds begin their northward migration from wintering grounds in Central America and Mexico as early as February, with males typically arriving first. Their return to specific North American regions is a gradual process, influenced by several factors. For example, Ruby-throated hummingbirds in the eastern United States reach Gulf Coast states like Texas and Louisiana by late February to mid-March.
As spring progresses, they continue northward. By early April, they appear in states like Virginia and Kentucky, and by late April to early May, they arrive in more northern states and Canadian provinces.
Arrival dates vary slightly year to year, depending on weather, early spring blooms, and increasing daylight hours. Western species, such as Rufous hummingbirds, travel up the Pacific Coast, reaching Washington and British Columbia by May.
Why They Return
Hummingbirds migrate north to access abundant food sources and suitable breeding territories. While tropical winter grounds offer warmth and insects, northern latitudes in spring and summer provide an expanded breeding range with plentiful nectar-producing flowers and insects.
This seasonal resource availability reduces competition for food and territory, which is intense in their tropical winter habitats. Longer daylight hours in northern regions also signal the optimal time for breeding and raising young. This instinct to migrate north is an adaptation that allows them to take advantage of the rich summer habitat. The larger northern breeding grounds support a greater population.
Preparing for Their Arrival
Prepare for hummingbirds by ensuring food and water are available upon their arrival. Set up feeders a few weeks before their expected return. A common nectar recipe is one part refined white sugar to four parts water; this can be mixed until dissolved and does not require boiling.
Do not add red dye, as it is unnecessary and potentially harmful. Never use honey, corn syrup, or raw sugars. Clean feeders thoroughly every other day to prevent mold growth, which can be detrimental to the birds.
Planting native nectar-rich flowers provides a natural, continuous food source. Examples include:
Bee balm
Cardinal flower
Columbine
Coral honeysuckle
Trumpet creeper
A clean water source, like a mister or dripper, also benefits hummingbirds, allowing them to bathe and preen for feather health and temperature regulation.
Life After Arrival
Upon returning to their breeding grounds, hummingbirds focus on reproduction and sustenance. Males typically arrive first, establishing and defending feeding territories about a quarter-acre in size. These territories provide access to prime resources like nectar-rich flowers or feeders, which males protect from rivals through aerial displays and chases.
Once females arrive, courtship rituals begin, often involving elaborate aerial acrobatics by males to attract a mate. After mating, female hummingbirds build nests, incubate eggs, and raise their young.
Nests are tiny, cup-shaped structures, typically built 10 to 90 feet high in trees or shrubs, often camouflaged with lichen and bound together with spider silk, allowing them to stretch as the chicks grow. Females usually lay two eggs, incubated for 15 to 18 days, with young fledging in 18 to 28 days after hatching.
The Journey Southward
As the breeding season concludes, hummingbirds prepare for their reverse migration back to warmer climates. Departure typically begins in late summer, around August or September, and continues through October. Environmental cues like decreasing daylight hours, cooler temperatures, and diminishing natural food sources trigger this southward journey.
Males often initiate southward migration first, followed by females and newly fledged juveniles. This staggered departure may reduce competition for dwindling resources along the migratory route. Many hummingbirds gain significant body weight, sometimes 25-40%, before embarking on this long journey to fuel strenuous flight, which can include non-stop segments over large bodies of water.