When to stop feeding hummingbirds is a common concern for Missouri residents who wish to support these tiny travelers without interfering with their natural instincts. The primary species observed is the Ruby-throated Hummingbird, a neotropical migrant that relies on substantial fat reserves to fuel its journey south to Central America and Mexico. Understanding the bird’s biological clock is the first step in timing the removal of feeders and providing responsible late-season care.
Understanding the Missouri Hummingbird Migration Schedule
The departure of the Ruby-throated Hummingbird from Missouri is a gradual process that begins in late summer. Most of the breeding population begins moving south in late August, with a noticeable decrease in numbers at feeders as September progresses. The peak of the southbound migration typically occurs in mid-to-late September, when the summer’s new, young birds join the adults on their journey.
By early October, the vast majority of Ruby-throated Hummingbirds have left the state, with only stragglers remaining. A general recommendation is to keep feeders maintained and clean at least through the first half of October to assist any late-departing individuals. This timeline ensures that local birds and those passing through from further north have access to a high-energy food source before crossing the Gulf of Mexico.
Migration is not triggered by dwindling food supplies, but by environmental changes signaling the shift in seasons. A primary driver is the decreasing length of daylight, or photoperiod, which causes hormonal changes within the birds. This innate biological mechanism prompts them to enter hyperphagia, consuming large amounts of nectar and insects to gain 25 to 40% of their body weight in fat before their journey.
Addressing the Myth of Delayed Migration
A frequent concern is the misconception that leaving feeders up too late will prevent the birds from migrating. This is not supported by scientific evidence, as the Ruby-throated Hummingbird’s biological clock is set by the photoperiod. The birds will migrate when their instinct tells them it is time, regardless of whether an artificial food source is available.
The presence of a feeder does not override the powerful, instinctive drive to fly south before winter. Any bird that remained too long would face freezing temperatures and a lack of the insects they rely upon for protein. The purpose of late-season feeding is simply to provide fuel for those already programmed to migrate.
Nectar availability serves only to top off the energy reserves needed for the long flight, which often includes a non-stop crossing of the Gulf of Mexico. Removing the feeder prematurely could eliminate a necessary refueling stop for a bird migrating from a northern latitude. Keeping the feeder available until the birds naturally depart is a supportive action.
Specific Guidance for Late Season Feeder Management
Once the main wave of migration has passed in early October, the guidance shifts to a monitoring approach. The best practice is to keep at least one feeder maintained for one to two weeks after the last hummingbird sighting. This provides a final opportunity for late travelers or rare vagrants, such as the Rufous Hummingbird, which occasionally passes through Missouri in the late fall, to refuel.
During this late-season period, diligent maintenance is important. The sugar water solution (one part white granulated sugar to four parts water) must be kept fresh, requiring changes every few days. As temperatures drop, monitoring for frost or freezing conditions is necessary, as the sugar water can freeze overnight, making it inaccessible.
If an unexpected cold snap occurs, a feeder can be temporarily brought indoors at night and replaced at dawn to ensure the solution remains liquid. Once two full weeks have passed without a sighting, the remaining feeders should be taken down, thoroughly cleaned with a diluted vinegar solution, and stored for the winter. This confirms that all local and passing migrants have had every opportunity to move on.