The Bewitching Common Yellowthroat -June 2017
by: Virginia Andrews
It’s a lovely morning in early June, the month “when, if ever, come perfect days,” and a song floats out of a nearby bush: “witchety-witchety-witchety.” There’s a pause, perhaps, and the phrase is repeated and completed, “witchety-witchety-witchety-witch!” It’s an assertive song, as strong as sunlight creeping through the blinds on a summer day. But it is also beguiling, an announcement that summer is indeed here. It is, of course, the bewitching Common Yellowthroat, a tiny warbler with a big song.
He – for it is the male who thus proclaims and defends his place – is a warbler, a migratory songbird that comes north every summer. A sharp eye will find the singer, often teed up at the top of a bush in a tangle near water. His throat is indeed bright yellow. But perhaps more striking is the black eye-patch, which gives him the nickname “masked bandit” among some birders. A bright white line tops the black mask. That and his golden throat make him readily identifiable from a front elevation. The back view is unmarked olive-brown, which makes for excellent camouflage. But when he is at home, he often sits still long enough to be seen, and song is the best way to find him.
It’s a simple sequence of two to five notes repeated three to five times, a bit squeaky, perhaps, with a hint of a rasp like the approach of a rusty bicycle, but melodic, repetitive. But birdsong is not as hardwired as ornithologists used to think. Within the basic structure there is room for personal expression. The bird can vary the number and intervals of notes, making him recognizable as an individual. With individual expression there must be meaning. Even without undue anthropomorphizing, birders speculate songs say many things: first of all, “I’m here.” And then, “this is my home, my territory.” And also perhaps, more importantly, “I’m available.” It is one of the ways male Common Yellowthroats find a Mrs. Yellowthroat. As in some other species, the best crooner is the most attractive. Song catches the ear and advertises his fitness and strength, not to mention his abilities as a good provider with a suitable homestead.
While many birds sing mainly in the morning or late afternoon, Common Yellowthroats sing at any time, although sometimes more frequently late in the day. There is a perch song and a flight song. The latter is his special signature, directed outward to the edges of his territory. He is most vocal during nest-building and incubation of eggs, but will continue to sing until the time of molting. After the wear and tear of raising a family, the summer plumage needs replacement. Most birds grow a new set of feathers two or even three times a year.
Brushy tangles, usually near water, provide all the resources a pair needs to raise a family. Mrs. Yellowthroat is as inconspicuous as her guy is flashy. Her plain brown head and back and dull yellow breast blend in with the shades and colors of sun-lit brush. While the male guards the homestead the female builds a nest of leaves, rootlets and grasses lined with fine grass and hairs. Settled on a nest, she disappears almost completely from view.
Once a pair has set up housekeeping, the male’s song becomes more conversational. But it can also convey a warning: “Danger! Predator nearby!” Both males and females respond sharply to perceived threats by giving “chip!” or “schtip!” calls. A female approached on the nest performs an impressive distraction display: an explosion of stuttered chips and emphatic squawks. She flutters up as if in broken-winged distress, flying to the attack with all the force her 9.9 grams of indignation can muster. It is disconcerting, to say the least, to have even so small a bird give such an in-your-face performance, and is usually a very successful distraction from a well-hidden nest containing three to five – sometimes six – eggs or young.
Common Yellowthroats can raise up to two broods per season if conditions allow. So why are we not completely overrun with them? The fact is, it’s a tough world out there. More than half will die before completing their first year. They have to learn the skills of finding food while escaping hawks, cats and other predators. On migration – some go as far south as Panama – they also have to avoid reflective glass, lit structures and bad weather.
Young birds begin with a warbled version of baby talk, and gradually learn to sing as they grow up. As in some other species, there are regional accents varying the duration and phrasing of song. With 13 different subspecies there are also numerous geographical plumage variations. But one race or another can be found in almost every corner of Massachusetts, across the United States from Alaska to Florida, and north as far as the Canadian Maritimes.
Because the first specimens collected for European science were bagged in Maryland, our bird used to be called the Maryland Yellowthroat. Eventually this morphed into the Northern Yellowthroat, distinguishing it from some of its Caribbean relatives. Currently called the Common Yellowthroat, it is still common. But breeding bird surveys have found a consistent decline in its numbers. Massachusetts Audubon has added it to its “whispering bird” category – still common – but for how long? We have seen a drop in numbers even on Nantucket. While 2014 appeared to be a banner year, with pairs everywhere, in 2015 and 2016, there seemed to be many fewer. This has been a trend across the eastern part of the United States. So ornithologists find that it is in need of careful monitoring. Are declines the result of natural variation, severe weather, climate change, pesticides, pollution? We don’t know – yet.
Studies of birds can tell us important details about our environment, which are not available in other ways. And despite the ubiquity of the Common Yellowthroat, there is still much more to learn about this delightful, bewitching little singer. ///
Virginia Andrews writes the weekly “Island Bird Sightings” column for The Inquirer and Mirror and is a regular feature writer for Nantucket Today.