PHOTO COURTESY OF GARRY KESSLER
Eastern phoebes are gray or gray-brown with a dark head and a light underside. Sometimes they have a green or yellow tinge underneath. Their habit of wagging their tail is a clue to identifying a phoebe from far away.
November 14, 2014, Page A5, A7
NATURE NOTES
By Annie Reid
Westborough Community Land Trust
Phoebes come early and stay late
November turns our entire landscape into a dried wildflower arrangement with a beauty of its own, yet we often think of this month as an empty time with no leaves, no butterflies, and no birds. Fortunately, we still have our resident birds – chickadees, nuthatches, cardinals, and more – and a few others that linger, including the eastern phoebe, a bird that comes early (in March) and stays late (often into November).
Eastern phoebes (Sayornis phoebe) are flycatchers. You’ll often find them in areas near water, since water usually means lots of flying insects. Because they depend on insect life for their food, phoebes depart when their food becomes scarce due to the cold. Most eastern phoebes overwinter primarily in the southeastern U.S., where temperatures are usually above freezing. They return here in early spring as the flying-insect world comes to life in our area.
Look for phoebes at the edge of a pond, trail, or field bordered by woods. This small gray bird with a dark head tends to sit quietly on a low branch, then suddenly fly out to snatch an insect out of the air with its beak, and return to the same branch or another one nearby to eat its meal and resume its watch. A phoebe’s diet includes insects such as bees and wasps, which these birds kill so quickly that they don’t get stung. Sometimes they’ll drop to the ground to catch an insect there. Occasionally they’ll eat small wild fruit. Not surprisingly, phoebes don’t tend to be feeder birds.
Male and female phoebes look alike, although males are slightly larger. The birds are gray or gray-brown, with darker heads and tails. Their undersides are light, sometimes with a green or yellow tinge. Adult phoebes have no eye rings, wing bars, or other markings, but juveniles may have faint wing bars.
How can you tell a phoebe from far away? One clue is its habit of wagging its tail, by giving a downward flick, even when perched and looking for food. Why do phoebes do this? No one knows for sure, but some experts think the movement helps to keep predators away.
Earlier in the year, you might have noticed phoebes closer to home. They like to nest under an overhang and often build their nests in human-made structures, such as sheds, bridges, and culverts, or under porches or the eaves of a building. Originally they nested mainly in rock outcrops, especially in wooded areas near water – where you can still find them nesting – but when European settlers arrived in North America, phoebes adapted their nesting habits to buildings and bridges. Since then, eastern phoebes have become widespread in eastern North America as we’ve filled the landscape with buildings and roads with bridges and culverts.
By this time of year, the nesting season is a distant memory. If you noticed a phoebe nest on a building or under a nearby bridge or culvert, check the spot again in early spring (March/April). In these protected places, a phoebe’s sturdy cup nest of mud, grass, and moss tends to survive the winter, and the same pair of phoebes is likely to return to it in the spring. The male usually returns first, with the female arriving two weeks later. They’ll refurbish the nest for re-use if possible.
How do phoebes carry mud to their nests? They collect it by dipping a beakful of dried grass into wet mud and then making the whole muddy wad part of the nest. Eastern phoebes typically raise two broods of young each breeding season and often use the same nest for both.
At any time of year, even before you see a phoebe, you might realize that one is nearby if you hear its distinctive simple song, which sounds like its name, “fee-bee.” The sound is short and raspy, hardly what we usually think of as “song.” People sometimes think the sweet-sounding, whistled “hey-sweetie” song of our black-capped chickadees belongs to a phoebe, but no. Once you’ve heard the phoebe’s song a couple of times, it’s hard to forget. Both males and females make the song, but males sing much more than females, especially during the breeding season. But even now, in fall, you might hear a phoebe saying its name in song.
Why do phoebes have such a simple, raspy song? One reason is that their voice boxes are simpler and have fewer muscles than those of the many songbirds that sing more melodious tunes. Phoebes don’t have the fine control of sound that cardinals, song sparrows, chickadees, and catbirds have. The “fee-bee” song comes in a couple of variations, as compared with nine songs for cardinals and song sparrows.
Phoebes sing their songs without having to learn them. Most young songbirds need to hear and imitate the songs of adults in order to learn their species’ songs, but young phoebes sing their own songs without this learning and practice. Genes may program phoebes to sing the way they do. In addition, research shows that phoebes don’t have the particular groups of brain cells that many other songbirds use in learning more varied and complex songs.
It’s fun to know a bird like the eastern phoebe, which is common and widespread in Massachusetts, yet there’s reason for concern about phoebes. Regular bird counts over four decades indicate that their numbers here have been gradually decreasing by an average of 1.7 percent a year (U.S. Geological Survey Breeding Bird Survey, 1966-2008, as reported in Mass Audubon’s State of the Birds 2011). Over time, this small decrease adds up. The declining trend raises a question about the long-term outlook for eastern phoebes in our state.
For now, enjoy keeping an eye out for phoebes that stay late into November, and look forward to watching for them when they return as early as March.