Kentucky Warbler

In 1810, acclaimed naturalist and ornithologist Alexander Wilson identified a new species of New World Warblers. Named after the state of its identification, the Kentucky Warbler, also known as the Geothlypis formosa is a small songbird seasonally found in the deciduous forests in the United States.

About Kentucky Warblers

The Kentucky Warbler has an aggressive song and beautiful plumage, the Kentucky Warbler is a migratory bird that spends summers in the dense forests in and around Louisiana and Mississippi.

You can see them hopping around the forest floor searching for prey, overturning the dense layer of twigs, leaves, and grass pecking for its meal. Upon being discovered they often retreat to the safety of the thickets in the forest, peaking its head out occasionally to check if the intruder is still in its territory. 

Over the past 60 years, population rates have steadily declined due to habitat loss and degradation caused by deforestation and the disappearance of forest understory in both the United States and their wintering grounds in Central America. When we look at their interesting history, it is natural that birdwatchers want to know all they can about this Warbler species.

● Kentucky Warbler Photos, Color Pattern, Song
● Kentucky Warbler Size, Eating behavior, Habitat
● Kentucky Warbler Range and Migration, Nesting

Kentucky Warbler Color Pattern

Males are bright yellow along the underside of their body, from the throat to the end of the tail, and olive-green from their nape to their tail. You can identify males by their black crowns and sideburns.

Females are similar in color and share the same bright yellow below and olive-green above. Instead of the black sideburns and crown, their sideburns are grey, and their crown is black or grey.

Both sexes have yellow underbellies and olive-green backs, wings, and tails. Immature Kentucky Warblers are duller than their adult counterparts. Upon maturation, the young Warbler’s plumages will attain the bright yellow characteristic of New World Warblers. All Kentucky Warblers have black eyes and pink legs. 

Description and Identification

The Kentucky Warbler is a shy bird that is often difficult to find due to the concealed nature of its nests, along with the reduction in its natural habitat due to deforestation. They have a bright plumage and spend most of their time on the ground level hunting for insect prey. However, finding them can often be a hard task since the shade from the dense forest conceals their whereabouts.

The Kentucky Warbler might be easy to confuse with many of its other Warbler cousins as many share the memorable bright yellow and olive-green plumage. Often confused with the likes the Hooded Warbler, the Kentucky Warbler can be identified through the lack of the namesake “hooded”. Look on their head and the facial markings that are present along the eyes, often called “spectacles” or “eyebrows”.

It’s often easier to depend on the much less concealed calls and songs of the Warbler. The constant repetition of the song is to defend their territory. This can assist you in the viewing and identification of the Kentucky Warbler.

Kentucky Warbler Song

Kentucky Warblers are songbirds, peculiarly for songbirds, the adult male Kentucky Warbler only sings one type of song. The adult male will only sing one song during his lifetime, unlike most birds that match each other’s song type while counter-singing. This song is often a short series of two-syllable phrases often coming through as a “churee churee” sound.

The male Kentucky Warblers use a song to defend their territory. They record this territorial vocalization persistently by every 12 seconds. The call of the Kentucky Warbler is a high-pitch “chip” sound.

Kentucky Warbler Size

The Kentucky Warbler is a small species of New World Warblers. Often the same size or smaller a Sparrow. Like most Warblers, there is no disparity in the size between males and females. They measure about 5 inches in length and weigh around 0.5 ounces. Though little birds, their wingspan measures a little less than double their length, ranging between 7.9-8.7 inches.

Kentucky Warbler Behavior

Males arrive from their wintering grounds around April-May and begin to establish their territory. They defend their territory by aggressively singing their “churee churee” song to ward off other males.

In a few days, female Kentucky Warblers arrive and begin the nesting efforts. The efforts begin with males attempting to court the female. In which the male and female chase each other around while making a rapid “chip” sound. Kentucky Warblers do this because they don’t have a song to attract mates.

Upon successful courting both sexes build a nest using plant materials that they build on the ground. They use small shrubs or other plants to conceal and protect their nest. Females then lay eggs and incubate them alone until the eggs hatch. At which point males begin to assist in feeding the hatchlings when they leave the nest. Both parents divide the care the responsibilities of taking care of the fleglings. They have to figure out who feeds and who cares for the young.

Kentucky Warblers are socially monogamous, therefore one female will only nest with one territorial male during the nesting efforts, but if the nesting efforts fail during the breeding season females often choose another mate, they almost never pair together beyond one breeding season. Curiously, males birds father over half of Kentucky Warbler nests.

Around July and August, they begin to leave for their wintering grounds, in which they do not breed. In fact, they mark territories in which they allow no other Kentucky Warblers, curiously they do it without the songs they use to ward off intruders in their breeding grounds.

Kentucky Warbler Diet

Kentucky Warblers love insects. They follow a varied diet of moths, ants, caterpillars, amphids, and just like its Bay-breasted Warbler cousin it too may include berries into its diet during winter. They have a special love for spiders, helping to balance spider populations in their habitats.

Kentucky Warbler Habitat

Kentucky Warblers are found in the deciduous forests in the east during the summer, living in the dense understory as they prefer moist, leafy woodlands as the dense shrubs and plants give the Kentucky Warbler safe space to nest and breed.  

These thickets also serve a location for food as these mostly ground-dwelling birds hunt best for their insect prey amongst the leaf-litter of these deciduous forests. This needs for moist forests often place them around sources of water such as marches, creeks, and rivers. For their wintering grounds, they prefer the undergrowth of moist tropical lowlands, and foothill second-growth forests, but also in mature tropical forests.

Range and Migration

Upon ending its summer stay in central and eastern United States, the Kentucky Warbler migrates south in search for warmer climates as winter sets in. Starting in June all the way to October Kentucky Warblers flies across the Gulf of Mexico to settle in Lowland Forests across Mexico and Central Asia.

As the climate begins to warm back up to their liking, starting in March the Kentucky Warblers begin to return to their summer breeding grounds. These little birds have a range of over 772,000 square miles stretched across Northern and Central America. Most populations found widespread west of the Appalachians.

Kentucky Warbler Lifecycle

Usually, Kentucky Warblers lay an average clutch of 3 eggs, it can be as low as 1 or up to 6. The Female Kentucky Warblers lay 2 broods. The eggs are a creamy white with brown speckles.

As females nest, the males protect the female always keeping the nest and the female in visual range. The males also feed the female during the incubation period, upon hatching the young are led by the female who is the primary caretaker, feeding and caring for the birds. The male also assists in the process.

The hatchlings begin to leave the nest about 8-10 days. Both sexes care for and feed the fledgling until they are ready to leave the nest. Kentucky Warblers live in the wild for 7 years, while the oldest was an 11-year-old female from Alabama.

Nesting

Kentucky Warblers build their nests either at ground level or at most a few inches above. They generally build their nests at the bottom of bushes, shrubs, grass tussocks, and bedstraws. On some occasions, they even nest in the lowest forks of small trees. The nests are built near ground level so they can easily be hidden by the dense foliage of the deciduous forests they inhabit.

The nest is built by both the male and female. Using rootlets, the core of weeds, grass stems, and leaves both Warblers together fashion a bulky open cup. The nests of the Kentucky Warblers are often parasitized by the eggs of the notorious Brown-headed Cowbirds that lays their eggs alongside the eggs of the Kentucky Warbler just as it does with its other Warbler cousins.

Anatomy of a Kentucky Warbler

Kentucky Warblers are considered small in size measuring around 5 inches in length. For small birds, they are quite bulky. They have pointy and thin bills with no curve to them. Their wings are average size, and they are rounded. The Kentucky Warblers tail is small, emarginate, and well-rounded lending to an almost fan-like shape. Their legs are long and thin with thin talons. Their heads are dome-shaped. Due to their plumage being “fluffy”, they appear to be slightly larger in size. 

Final Thoughts

Population declines of the Kentucky Warbler have been recorded since mid 1970 across the entire habitat. The loss and degradation of habitat due to timber extraction and development has left the Warbler in a precarious position as it needs forest understory, which takes decades to develop and is not present in all forests.

Threats to its existence are many, the overabundance of White-tailed Deer that is the cause of disappearance to Forest understory. Another threat is the invasive species of Emerald Ash Borers that reduce the regeneration of the trees in the Warblers habitat. Climate change has taken some territory from the Kentucky Warblers due to the reduction of suitable territory for the growth of floodplain forest. It has also increased the area suitable for the growth of hardwood forests which can serve as breeding grounds for them if the expansion is conducted.

This loss of habitat is present in its summer grounds within the United States and its wintering grounds in Central America due to which partners in flight has placed the Kentucky Warbler is in their Yellow watch list. If attempting to find these birds one is more likely to hear it than ever see it, during their early breeding season during March-April through the songs of their territorial defense and high-pitched chips. Beyond the initial defense and courting the
Kentucky Warbler returns to being the shy birds they are known to be, with no loud singing to attract your attention. A birdwatcher’s best bet is to search along the forest floor for the little Warbler hunting for prey or catch a view of their migratory patterns across Louisiana and Mississippi to their wintering grounds.

Ornithology

Bird Watching Academy & Camp Subscription Boxes

At the Bird Watching Academy & Camp we help kids, youth, and adults get excited and involved in bird watching. We have several monthly subscription boxes that you can subscribe to. Our monthly subscription boxes help kids, youth, and adults learn about birds, bird watching, and bird conservation.

Bird Watching Binoculars for IdentifyingKentucky Warblers

The most common types of bird watching binoculars for viewing Kentucky Warblers are 8×21 binoculars and 10×42 binoculars. Bird Watching Academy & Camp sells really nice 8×21 binoculars and 10×42 binoculars. You can view and purchase them here.

Kentucky Warbler Stickers

Stickers are a great way for you to display your love for bird watching and the Kentucky Warbler. We sell a monthly subscription sticker pack. The sticker packs have 12 bird stickers. These sticker packs will help your kids learn new birds every month.

Bird Feeders ForKentucky Warblers

There are many types of bird feeders. Bird feeders are a great addition to your backyard. Bird feeders will increase the chances of attracting birds drastically. Both kids and adults will have a great time watching birds eat at these bird feeders. There are a wide variety of bird feeders on the market and it is important to find the best fit for you and your backyard.

Bird HousesForKentucky Warblers

There are many types of bird houses. Building a bird house is always fun but can be frustrating. Getting a bird house for kids to watch birds grow is always fun. If you spend a little extra money on bird houses, it will be well worth every penny and they’ll look great.