The temperatures may be dropping but hummingbirds are still around in Utah, even in late September and early October. Understanding when hummingbirds begin their fall migration can help backyard birders in Utah County know how long to keep up hummingbird feeders and what hummers to expect at different times in autumn.
Utah's Late Season Hummingbirds
The resident broad-tailed hummingbirds depart first for their southern winter range, leaving as early as the beginning or middle of August, and by the end of August these hummers with their sparkling red throats and orange-edged tails are usually gone from all but the southernmost part of the state. Also leaving early are the calliope hummingbirds, which are much rarer in the state but are found in northern Utah each summer.
The most common Utah hummingbird, the black-chinned hummingbird, leaves at the end of August through mid-September, and all of these purple-throated birds are gone by the end of September. They are replaced by the more aggressive rufous hummingbirds, incoming migrants that arrive from their northern breeding range in Alaska and the Pacific Northwest beginning in August. The rufous hummingbirds stay in Utah as late as the end of September or even into mid-October, so long as weather conditions are mild and food remains available.
No matter what the species, mature male hummingbirds migrate earlier in the season, and feeders can seem overwhelmed with females later in fall – though many of those "females" are actually young male birds that have not yet developed the colorful gorget characteristic of their gender. Mature females leave next, and immature hummingbirds of both genders migrate last.
Helping Fall Hummers
Utah birders should keep their hummingbird feeders filled with fresh nectar at least until the first week of October, or until a week has passed with no hummingbird sightings at the feeders, whichever is later. Increasing the sugar concentration of the nectar very slightly can also help provide these birds a richer calorie source for extra energy, but avoid creating thick syrup they will not be able to drink. Planting fall containers of nectar-rich flowers can provide even more food sources for these hungry migrants, helping them fill up for their strenuous migration.
How late have you seen hummingbirds in Utah? Share your sightings in the comments, and learn more about when hummingbirds migrate!