Warblers – From A to Y

A ‘who’s who’ guide to these entertaining pint-sized songbirds

“For people who are tuned in to warblers, each day in migration season is like a treasure hunt: We never know which ones we’ll find.”

— Kenn Kaufmann

Sometimes, a writer wanders into a forest and can’t find his way back out. He sets off down a well-trod trail, but then something in the canopy catches his curious eye. So, he follows the bright, flitting bird into a cathedral of trees. Then he spots another bird … and another … and another. And he follows each of them until he finally stops, looks around, and realizes he hasn’t a clue how to get back on the path.

That’s where I found myself after accepting an offer to write a story about wood-warblers.

Of the 115 species in the family Parulidae, about half are tropical residents and half are long-distance migrants that nest in North America and winter in the Tropics. Over 40 species have been recorded in Missouri, over 30 turn up with regularity, and over a dozen nest here.

Unless you’re a birder, you probably don’t notice this tropical reef of small, brightly colored birds that wash, wave after wave, into our forests, woodlots, and tree-lined backyards every spring. My intent, as I bushwhacked through thickets of species accounts, was to write a story that would change that.

But good writing — the kind that makes you care — is specific and precise and eschews generalities. With 40-plus species to cover, how could I be anything but general?

My way out of the woods was to forgo the idea of a traditional narrative and instead write a series of short sketches for 30 of Missouri’s most common warblers. Though brief, I hope these offer a nugget of something interesting — perhaps even fascinating — about each bird.

A warbler is a hyperactive, ravenous little creature, akin to a sentient caffeine molecule that flickers like a sunburst through the treetops and suddenly disappears, Harry Potter-style, before you can hoist up your binoculars.

Often, all you get is a brief look. A flitting flash of color. And then it’s gone.

But that doesn’t make the moment any less magical.

Species Sketches

American redstarts are so named for their flash-and-flush hunting technique. As a redstart hops from branch to branch, it droops its wings and flicks open its tail, revealing garish Halloween-orange spots. (Females and immature males have lemon-yellow spots.) The sudden flash of color startles leafhoppers and other insects, which flush from their hiding places only to be snapped up by the hungry hunter. Redstarts are illustrative of the frenetic pace at which most warblers move. One study found that foraging redstarts change perches, on average, 27 to 30 times per minute.

Warblers shine brightest in the spring. In the fall, their sunshine-yellows and lime-greens fade to drab gray tones, like Dorothy returning to Kansas from the Emerald City. The somber colors can be confusing to birders, and none generate more consternation, perhaps, than bay-breasted and blackpoll warblers. In spring, the two birds look nothing alike. Bay-breasted males have a reddish-brown wash on the crown, neck, and flanks. Blackpoll males are black-capped and strikingly streaked. But in fall, both species transform into nondescript, mirror images of each other, so similar in appearance that frustrated birders sometimes list an unidentifiable bird as a “baypoll.” If you find yourself in a similar predicament, the Cornell Lab of Ornithology offers this advice: “One surefire way to distinguish them is by the color of the soles of their feet — bluish-gray in bay-breasted, yellow in blackpoll.” Good luck with that.

The black-and-white warbler’s genus, Mniotilta, means “moss-plucking.” It’s a fitting description for this bird’s un-warbler-like habit of creeping along tree trunks and limbs like a nuthatch, using its decurved bill to probe for insects hiding in the bark. At first glance, males and females appear similar, but closer inspection reveals subtle differences, the most noticeable being that females lack the broad black ear patch of males. Black-and-whites are one of about a dozen warblers that nest in Missouri. They build cup-shaped nurseries in Ozark leaf litter, usually at the base of a tree or against a log.

In 1958, a graduate student named Robert MacArthur turned in his dissertation and turned what we know about how nature works on its head. And he did it by watching warblers. According to Gause’s Law, species that compete for the same limited resource cannot coexist. One will eventually outcompete the others. But warblers in the spruce woods of Vermont and Maine seemed to defy this foundation of ecology. Five species — including the spectacular, flame-faced blackburnian warbler — nest in the same spruce trees and eat the same insects. How, then, could they coexist? MacArthur’s insight was to painstakingly track where each warbler spent its time. He found that blackburnian and Cape May warblers frequented the tops of trees, bay-breasted and black-throated green warblerssplit up the inner and outer branches midway up, and yellow-rumped warblersstayed lower down. MacArthur’s careful observations offered evidence that multiple species could coexist if they used the resource in subtly different ways. His dissertation is one of the most frequently cited papers in ecology, and this concept of resource partitioning is still being studied and refined today.

Blackpoll warblers pass through Missouri in the spring, en route to breeding grounds in the spruce and fir forests of Alaska, Canada, and the northeastern U.S. But in the fall, nearly all blackpolls — even those that nest in Alaska — travel to the East Coast and then migrate south over the Atlantic Ocean. Once they reach the Tropic of Cancer, trade winds deflect the half-ounce birds westward toward landfall in South America. This open ocean crossing — thought to be the longest made by any songbird — can span 1,800 miles and take up to 88 hours of nonstop flight.

Black-throated green warblers get chatty during nesting season. Lemon-headed males will pick a conspicuous perch high in the treetops and belt out song after song. Often described as a buzzy, high-pitched zoo-zee, zoo-zoo-zee, some birders remember it as trees, trees, I love trees. Regardless of what it sounds like to your ears, the warblers themselves seem to enjoy it. One motor-beaked male sang 466 songs in an hour.

On their boreal breeding grounds, Cape May warblers are budworm specialists. Nearly a third of their diet is composed of these inch-long, reddish-brown caterpillars, and Cape May populations swell during budworm outbreaks and shrink during budworm declines. But on their wintering grounds in the Caribbean, they supplement their insectivorous diet with fruits and nectar. As an adaptation for lapping up nectar, a Cape May’s tongue is curled and somewhat tubular.

Cerulean warblers are striking birds, but to see one, you have to crane your neck and peer high into the canopy of an old-growth, bottomland forest. Once abundant throughout the Ohio and Mississippi river valleys, cerulean numbers have plummeted more than 65 percent since the 1960s. The Ozarks continue to be a stronghold for the species, and a hike along a spring-fed stream in late May might reward you with an interesting sight: When leaving her nest, a female cerulean will sometimes hop over the side and drop vertically with her wings tucked closed. Only after she’s fallen well below the nest will she take flight. Biologists who have observed this unusual behavior call it “bungee jumping.”

Dapper and diminutive, chestnut-sided warblers leverage their size to forage in places heavier warblers can’t reach. Often seen hopping from perch to perch in the skinny outer branches of shrubs and trees, these acrobatic birds capture nearly 70 percent of the insects they eat from the underside of leaves. (On their wintering grounds in Central America, they capture about 90 percent of their prey from under leaves.)

Common yellowthroats are one of North America’s most widespread warblers, breeding throughout the U.S. and Canada except for the Desert Southwest. They frequent dense, low-growing vegetation, often at the edges of marshes and other wet areas. Their persistent wichity-wichity-wichity calls make them easy to locate, but their habit of sneaking through tangled vegetation means they’re not always easy to see.

Although the two birds look nothing alike, golden-winged warblers and blue-winged warblers share 99.97 percent of their DNA. They hybridize frequently, and their offspring express a range of characteristics from both species. Two phenotypes occur often enough to be named: Brewster’s warbler, which looks like a blue-wing with a white belly, and Lawrence’s warbler, which looks like a golden-wing with a yellow belly. Blue-wings have expanded their range in the past century, while golden-wing numbers have dropped precipitously, partly as a result of competition and hybridization with their close cousins.

Male hooded warblers wear a distinctive black hood with a golden-yellow mask. First-year females have few, if any, black feathers on their heads, but older females vary extensively in their headwear. Some have little or no black, while others have complete dark hoods and look nearly identical to males. On their breeding grounds, which include southeastern Missouri, each male sings a distinctive song (at least distinctive to other hooded warblers). Males remember their neighbor’s songs from year to year, which is thought to decrease the amount of energy they must spend defending territories. When hunting insects, hooded warblers flick open their tails to reveal startling white spots, a behavior similar to American redstarts.

Many male warblers sing two types of songs — one to attract a female and a different (though similar-sounding) one to defend a territory. Kentucky warblers are more utilitarian, singing only one song for both purposes. Listen for their bright, rolling warbles ringing through the thick understory of bottomland forests across Missouri. Just be aware that to the untrained ear, a Kentucky warbler’s song sounds similar to the teakettle-teakettle-teakettle of a Carolina wren.

With their brown base colors and boldly streaked chests, it’s easy to see how Louisiana and northern waterthrushes — which are warblers, not thrushes — got their names. Although they’re not known to hybridize, both species habitually bob their tails and look incredibly similar. Several clues help tell them apart — Louisiana waterthrushes prefer to forage near running water; northern waterthrushes usually forage along the edges of stagnant pools like marshes. Louisiana waterthrushes have an unmarked or lightly streaked throat; northerns have extensive streaking on their throats. And lastly, Louisiana waterthrushes nest in Missouri; northerns pass through in spring on their way to northern nesting grounds.

Often, the only look you get of a warbler is its underside. Because of this, hardcore birders memorize warbler tail patterns, many of which are distinctive and all that’s needed to ID a species. Magnolia warblers, both the strikingly patterned adult males and the slightly less-striking females and immatures, have diagnostic tail patterns — a wide white band against the body with a wide black band at the tip of the tail.

Although they’re named after a town in Tennessee, Nashville warblers nest far north of the state. Two separate populations breed in North America, one east of the Mississippi River and another in the Pacific Northwest. Nashvilles nest in a variety of brushy, second-growth habitats, and, unlike many warbler species, their numbers have stayed steady or even increased slightly during times of extensive forest clearing.

Springtime brings an odd affliction to birders. Commonly known as “warbler neck,” it is diagnosed by persistent pain in the capitis and trapezius muscles caused by spending hours peering into the tops of trees. Northern parulas — dainty, brilliantly colored, and canopy-loving — are a leading cause of the condition. In southern states, parulas hide their hanging, pouchlike nests in dangling Spanish moss. In Missouri, they hide them in tufts of beard moss (which is actually a lichen). This secretive habit, along with their propensity to live high in the canopy, makes it difficult to study their nesting behavior.

Ornithologists continually refine the number of bird species throughout the world. Using genetic analysis, seemingly unrelated species are sometimes lumped together as one species. Conversely, other individual species are split into two or more different species. In 2025, what was previously known as the yellow warbler was split into the migratory northern yellow warbler (which visits Missouri) and the non-migratory mangrove yellow warbler. Brown-headed cowbirds frequently dump their eggs in yellow warbler nests. When a female finds her nest parasitized by a cowbird, she often builds a new nest atop the unwelcome egg (and, unfortunately, any of her own). If cowbirds persistently return, this behavior can result in a stack of up to six nests.

One of the few Parulids that is more common in the west than the east, orange-crowned warblers pass through Missouri in both spring and fall. The orange crown is rarely seen in these relatively nondescript warblers. It’s usually visible only when an agitated bird raises its head feathers. On their nesting grounds, males form “song neighborhoods,” where several birds in adjacent territories mimic each other’s distinct song patterns. These neighborhoods have been recorded to persist for over a decade.

Cryptically colored ovenbirds are more often heard than seen. The poet Robert Frost immortalized the male’s exuberant teacher-teacher-teacher song like this: “There is a singer everyone has heard, Loud, a mid-summer and a mid-wood bird …” Ovenbirds nest in mature forests throughout Missouri. Females clear out a circular area among leaf litter on the forest floor, weave a domed nest, and camouflage the top with leaves and sticks. The structure resembles a Dutch oven, which is where the species gets its name.

Although its name conjures images of tropical beaches, palm warblers nest in the boreal forests of far northern Canada. In fact, among warbler species, only blackpolls nest at higher latitudes. Palm warblers winter in the Caribbean and along the Gulf Coast, migrating through Missouri in spring and fall. Males and females look identical, but eastern birds have more yellow on their bellies compared to western birds. Both subspecies nervously twitch their tails as they forage along the ground.

Pine warblers are well-named. They nest in pine forests, including those in southern Missouri and northern Arkansas. And, although insects comprise most of their diet, their sturdy bills allow them to be one of the only warblers to regularly eat seeds (especially pine seeds). Most Parulids are long-distance migrants that spend winter in the Tropics. But pine warblers winter primarily in the southeastern U.S. This — along with their seed-eating ability — allow these elegantly subtle warblers to migrate into Missouri in early March, usually the first to herald the oncoming rush of spring migrants.

Named for the color of the robes worn by papal clerks in the Catholic church, prothonotary warblers blaze like a ray of pure sunshine in their swampy haunts. One of only two warblers to nest in tree cavities (the other is Lucy’s warbler, a western species), prothonotaries often use holes excavated by downy woodpeckers. Sometimes called “swamp warblers,” prothonotaries nest in soggy bottomland forests along the edges of big rivers.

Tennessee warblers nest far north of Tennessee, in the spruce forests of Canada and Maine. In winter, they frequent shade-grown coffee plantations in Central America and the Caribbean. Like several other Parulids, Tennessee warblers supplement their diet of insects with fruits and nectar in winter. They are an unrepentant nectar thief of tubular tropical flowers, using their sharp bills to pierce flower tubes and “steal” sweet nectar without distributing any of the plant’s pollen.

You won’t get warbler neck from searching for Wilson’s warblers, but you might tweak a nerve trying to follow this energetic yellow floof as it bounces among the underbrush. One of the continent’s smallest and most widespread warblers, Wilson’s employ a variety of behaviors on their wintering grounds. Some vigorously defend territories, others float among territories, and still others join mixed-species flocks.

Unfortunately misnamed, worm-eating warblers eat insects and spiders, not earthworms. These cryptically colored warblers are among a suite of ground-nesting Parulids in the Ozarks, which includes Louisiana waterthrushes, ovenbirds, black-and-white warblers, and Kentucky warblers. If flushed from her nest, a female worm-eating warbler often flutters low across the ground, then fans out her wings and tail, acting injured to lure predators away.

Yellow-rumped warblers were once considered two separate species — myrtle warblers in the east and Audubon’s warblers in the west. As a single species, they are one of the most widespread and common warblers in North America. “Butterbutts,” as they’re often nicknamed, owe their success to a jack-of-all-trades approach to foraging. They hunt at a variety of vegetation levels, gleaning insects from leaves, capturing flying insects with quick sallies, and eating berries and other fruits in winter. Though yellow-rumps nest north and west of Missouri, their wintering habitat includes the southern half of the Show-Me State.

With a brilliant, goldenrod-colored neck, yellow-throated warblers command attention. But you’ll have to crane your neck to spot one. These dazzling birds typically sing, forage, and nest high in the forest canopy in the southeastern U.S., including Missouri. Luckily, they move more methodically than other warblers, creeping around branches like nuthatches and probing into crevices with their beaks for insects. In the fall, yellow-throated warblers don’t fly far, spending winter along the Gulf Coast and in the Caribbean. 

Matt Seek is the editor of Xplor, MDC’s magazine for kids.