Hummingbirds are a common sight in Ohio during warmer months, bringing bursts of color and energy to gardens. These tiny birds, primarily the Ruby-throated Hummingbird, are migratory visitors. They spend their breeding season across eastern North America before embarking on a journey each autumn.
Typical Departure Timeline
Ruby-throated Hummingbirds begin their departure from Ohio in late summer, with migration generally spanning from late August through September. Adult males are typically the first to migrate south, often starting in early to mid-August. Following the males, adult females and the year’s young birds start their migration. By the end of September, most hummingbirds have left Ohio, with very few remaining into October. While precise departure dates can vary, this late summer to early fall window marks their general exit from the region.
Factors Driving Migration
Several environmental cues signal to hummingbirds that it is time to begin their migration. A primary trigger is the decreasing duration of daylight hours, also known as photoperiod. This prompts them to prepare for their journey. Along with diminishing daylight, dropping temperatures and a reduction in available food sources, such as nectar-producing flowers and insects, also contribute to the migratory impulse. These factors indicate that breeding grounds will soon become unsuitable, prompting them to seek warmer climates with abundant resources.
The Journey South
Once they leave Ohio, Ruby-throated Hummingbirds travel to their wintering grounds, primarily located in Central America and southern Mexico. Their winter habitats can extend as far south as Panama, encompassing countries like Belize, Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua. While some may overwinter along the U.S. Gulf Coast, most continue further south. This migration covers thousands of miles.
A significant part of their journey involves a non-stop flight across the Gulf of Mexico, a distance of approximately 500 miles. This challenging crossing can take 18 to 22 hours to complete. To fuel this undertaking, hummingbirds must build up substantial fat reserves before departure, often increasing their body weight by two-thirds or more. They can utilize a state called torpor, a temporary lowering of body temperature and metabolism, to conserve energy and accumulate fat stores during the late summer. During migration, they typically fly during the day, stopping periodically to refuel on nectar and insects, though the Gulf crossing often occurs at night.