The annual spring migration of the Ruby-throated Hummingbird is a much-anticipated event for residents across Virginia. These birds undertake a journey from their wintering grounds in Mexico and Central America to reach their breeding territories in North America. Their return signals the start of spring, bringing emerald green and ruby red flashes to backyards throughout the state. The timing of their arrival is predictable, following a specific pattern as the birds move northward.
The Predictable Arrival Window in Virginia
The initial wave of Ruby-throated Hummingbirds typically begins to reach Virginia in the final weeks of March, though the main population arrives throughout April. This arrival is staggered based on latitude, following warming temperatures and the bloom of early nectar sources. The first sightings usually occur in Southern Virginia and the Tidewater regions, such as Chesapeake and Hampton Roads, appearing between April 1 and April 15.
As the season progresses, the migratory path continues northward. Central Virginia and the Richmond area see the main influx shortly after the southern coast, while northern and higher-altitude regions can expect arrivals later in the month. The earliest birds are adult males, who travel ahead to establish and defend breeding territories. Females and younger birds follow a few days or weeks later.
Factors Influencing Migration Timing
While the historical average provides a reliable window, the arrival date can shift based on environmental cues the birds experience along their route. The primary drivers for the start of migration are the increasing duration of daylight hours and hormonal changes within the birds. These internal signals propel them away from their wintering sites.
Once migrating, local weather conditions can accelerate or delay their journey into Virginia. Sustained warm temperatures encourage faster travel, while a late-season cold snap can cause the birds to pause their migration at stopover points. The availability of natural sustenance, such as early blooming flowers and small insects, is also a guiding factor. Recent studies suggest that hummingbirds are now arriving earlier in their breeding grounds, a shift potentially linked to broader climate patterns.
Preparing for Their Return
Preparation should begin well before the earliest expected March arrival date. Feeders must be thoroughly cleaned with hot water and a brush to remove residual mold or bacteria from the previous year. Setting out feeders one to two weeks before the earliest expected arrival ensures a ready food source for the first males.
The nectar solution is simple and safe, requiring a ratio of one part granulated white sugar to four parts water. The mixture should be boiled briefly to dissolve the sugar and then cooled before filling the feeder; no food coloring or artificial sweeteners should be used. Placing feeders in a semi-shady location slows the fermentation of the sugar water, which should be changed every two to three days in warm weather. Position the feeders away from large windows and domestic predators to provide a safe feeding environment.
The Fall Departure Schedule
The annual cycle concludes when the Ruby-throated Hummingbirds begin their southbound journey back to their wintering grounds in the late summer and early fall. Departure typically starts in late August and continues through September, with most of the population having left Virginia by early October. This migration is staggered by gender and age, in the reverse order of their spring arrival.
Adult males are the first to depart, sometimes leaving as early as mid-July or late August after breeding duties are finished. Females and young birds born that summer follow later, with juveniles making the journey south alone. It is important to leave feeders up for at least two weeks after the last sighting. This ensures that late-migrating individuals have access to the calories they need to fuel their journey.