Hummingbirds are a familiar and captivating presence in Minnesota during warmer months, known for their iridescent plumage and rapid wingbeats. These tiny, energetic creatures dart among flowers, feeding on nectar with incredible speed. Their presence is seasonal, as they undertake remarkable migratory journeys each year. This article explores when these birds typically depart from Minnesota.
Understanding the Departure Timeline
Ruby-throated Hummingbirds, the most common species in Minnesota, begin their southward migration as summer transitions to autumn. Most of these birds typically depart from the state between late August and early September. Some individuals may linger into late September, especially if weather conditions remain mild.
The primary environmental cue for departure is decreasing daylight hours, a phenomenon known as photoperiodism. As days shorten, it signals to the hummingbirds that winter is approaching, prompting their migratory instincts. Cooler temperatures also contribute, although food sources like nectar and insects typically remain sufficient into early fall. Their departure is driven by an innate biological clock rather than a lack of food.
This genetically programmed response ensures they leave before harsh winter conditions make survival difficult. Young hummingbirds, born during summer, also undertake this journey, often migrating independently. Their precise departure timing can vary slightly based on local weather patterns, but the overall window remains consistent.
The Hummingbird’s Journey South
Before their journey, hummingbirds engage in intense feeding to build fat reserves. They consume large quantities of nectar and supplement their diet with small insects and spiders, which provide protein. These fat reserves serve as the primary fuel source for their long-distance flight.
The journey is a feat for such small birds, often covering thousands of miles to reach their wintering grounds. Most Ruby-throated Hummingbirds from Minnesota migrate to areas along the Gulf Coast of the United States, Mexico, or Central America. A portion of their migration involves a non-stop flight across the Gulf of Mexico, which can take 18 to 22 hours.
During migration, hummingbirds face numerous challenges, including strong winds, storms, and predation. Despite these perils, their instinctual drive propels them forward. It is a common misconception that hummingbirds will starve if feeders are removed too early; their migration is driven by instinctual cues, not by a lack of food. Keeping feeders clean and full until late in the season can offer a valuable energy source for these travelers as they prepare for or pass through.