The return of hummingbirds to East Tennessee marks a sign of spring after their long migration from Central America and Mexico. The primary species making this journey is the Ruby-throated Hummingbird, the only hummingbird species that nests in the eastern United States. These tiny, iridescent travelers begin to appear in the region as temperatures warm, signaling the start of their breeding season.
The Specific Spring Arrival Window
The first Ruby-throated Hummingbirds, often called “scouts,” typically begin to appear in East Tennessee starting in mid-March. This initial wave is generally composed of the male birds, which travel ahead to establish and defend feeding territories before the females arrive. The main population influx occurs throughout late March and into the first two weeks of April, marking the start of the summer residency period.
The specific timing can slightly depend on the latitude; areas further south may record sightings a few days earlier than those closer to the northern border. By mid-April, the region is usually saturated with the returning migrants, who are ready to begin nesting. It is recommended to have feeders ready by the beginning of April to ensure arriving birds have an immediate food source after their strenuous journey.
How Weather Affects Migration Timing
The exact date of arrival is not fixed and varies each year based on environmental conditions, primarily temperature and wind patterns. Hummingbirds follow the emergence of nectar-producing flowers and insects, which are directly influenced by regional temperatures. A warmer-than-average late winter can encourage an earlier push north, sometimes seeing the first birds arrive even before mid-March.
Conversely, a prolonged cold snap or a late winter storm can significantly delay their journey into East Tennessee. These birds rely heavily on prevailing winds to conserve energy during their long-distance flight, and unfavorable winds can slow their progress. If a cold front drops temperatures significantly, the birds will often temporarily halt their migration further south until warmer conditions ensure adequate food availability upon arrival.
Essential Feeder Preparation Steps
Preparation for the hummingbirds’ arrival involves setting out clean feeders filled with a specific nectar solution. The ideal mixture consists of four parts water to one part granulated white sugar. This 1:4 ratio should be boiled briefly to help the sugar dissolve and inhibit microbial growth, then cooled completely before being placed in the feeder.
Avoid using red dye in the sugar water, as it offers no benefit to the birds and may be harmful to their health. The red color on the feeder parts themselves is sufficient to attract attention. Feeders must be cleaned frequently, especially as the weather warms, which can cause the sugar solution to ferment or grow mold quickly.
During warm weather, the nectar should be replaced and the feeder thoroughly cleaned every two to three days. Cleaning involves disassembling all parts and scrubbing them with hot water and a bottle brush to remove residue or mold. A diluted solution of white vinegar (two parts water to one part vinegar) can be used to sanitize the feeder, followed by a thorough rinse with plain water. Optimal feeder placement involves hanging them in a shaded area to slow fermentation, yet close to protective cover like trees or shrubs.
The Autumn Departure Timeline
The Ruby-throated Hummingbirds spend the summer months in East Tennessee before beginning their southward migration. Their departure typically starts in late August, with the majority of the population leaving throughout September and into early October. This autumn journey is often more noticeable than the spring arrival, as both adult birds and the new young of the year gather to fuel up for the strenuous trip.
For their journey, the birds will double their body mass to build up the fat reserves necessary to sustain a non-stop flight across the Gulf of Mexico. Backyard feeders play an important role during this period, providing concentrated energy sources. Leaving feeders up late does not prevent the birds from leaving; their internal biological clock and decreasing daylight hours trigger the instinct to migrate. Keeping feeders clean and full until at least mid-October ensures that any late-migrating or passing birds have the fuel they need.