The Tail Wagger Returns

I recently heard a raspy “feee-beee,” one of the sure sounds of spring—it was an Eastern Phoebe (Sayornis phoebe) singing and just back from its wintering grounds in the southeastern United States.

The Eastern Phoebe is a member of the Tyrant Flycatcher family, the Tyrannidae. It has a grayish back with a darker gray head and whitish belly. The best way to tell it apart from the similar Eastern Wood Pewee (Contopus virens) is by its behavior. Phoebes constantly wag their tails up and down.

I have often wondered why flycatchers that hunt flying insects in mid-air return so early in the year, in late winter and early spring. The weather is so fickle then, often changing from sunny 60°F (15°C) days to blustery storms with ice and snow. How do they survive when there aren’t many flying insects around?

A clue might be where they like to nest. These birds once only nested in places like the natural shelves created by rocky crevices in ravines. Humans-created ledges, such as the eaves of barns and other buildings, as well as under bridges, are perfect nesting places for them. These are also precisely where insects and spiders go to get out of the wind and weather. Phoebes take advantage of this by gleaning such prey from the beams and walls. When the weather warms, the birds hunt in sunnier locations and when insects are flying. Flycatchers, including the Eastern Phoebe, are known for “hawking” or “sallying”—flying out suddenly from a perch, grabbing a flying insect, then returning to the same place. Their prey includes beetles, flies, grasshoppers, bees, and wasps.

Eastern Phoebes, because they often nest along forest edges, are particularly vulnerable to nest predation by the Brown-headed Cowbird (Molothrus ater), a nest brood parasite. Once a female cowbird spots a phoebe nest with eggs, she’ll lay her own egg in it. The phoebe parents won’t recognize this egg as different from their own. When the eggs hatch, the much larger cowbird chick will get more food, decreasing the phoebe chicks’ chances of successfully fledging.

Despite this, Eastern Phoebe populations are stable now, which might have to do with their willingness to nest on human structures. They also adapt by feeding on fruit from plants such as Pokeweed (Phytolacca americana), Wild Grape (Vitis spp.), Virginia Creeper (Parthenocissus quincefolia), Poison Ivy (Toxicodendron radicans), and more, particularly during the winter months and when first returning north.

Phoebe pairs often return to the same nest every year and just refurbish it. This was discovered by noted naturalist and painter John James Audubon. In 1803, Audubon put silver thread on the legs of a brood of chicks near his home in Pennsylvania. The following year he captured two of these chicks that had returned. This is the first documented case of a banded bird returning. Banding today is an important way for scientists to learn more about bird life histories and migratory routes. Perhaps the phoebes you see in your neighborhood are old friends that come back year after year.