Kirtland’s Warbler (KIWA)

Setophaga kirtlandii

Male Kirtland’s Warbler © Bryan Calk  / Macaulay Library
Female Kirtland’s Warbler © James Lees / Macaulay Library

Range

The Kirtland’s Warbler is a very rare bird to see due to their near extinct population. They breed in a few scattered forests in upper Michigan and Wisconsin, and spend the winter in the Bahamas and Turks and Caicos Islands.

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Identification

The Kirtland’s Warbler is a small passerine with a steel gray head, gray and black streaked wings, and a bright yellow throat and belly. In males, the small triangular bill is masked with jet-black feathers connecting to the eyes, while underneath the yellow throat continues down the entire body of the bird. There is slightly gray and white streaking on the side of the chest in males, but most of the streaking lies on their wings, with each individual feather having shades of gray, black and a striking white outline. The eyes of the Kirtland’s Warbler are similarly outlined with bright white. The birds have a plain gray tail but a bright white rump which is best seen in flight.

Females, although surprisingly also possessing a bright yellow belly, lack a black eye mask, and have greater streaking down the chest and belly. The gray on a female’s head and back is generally duller compared to a male, but the distinctive white eye-ring means the species is easily identifiable regardless of gender.

When in breeding season, the male’s song can be heard throughout its pine habitat, since the Kirtland’s Warbler’s courting display is mainly extensive singing and aerial antics. Once the males have shown off their vocal and flight displays, they will fight off any competition that tries to enter their territory, and if chosen by a female, will instantly begin building a nest. The male’s song is a series of short high pitched but very clear couplets of notes, in which syllables are added or deleted by choice. When other birds are not in sight, the Kirtland’s Warbler has a short, low-pitched note that they use to communicate with each other.

Listen to its songs and calls here.

Habitat

The Kirtland’s Warbler is one of the rarest songbirds to spot in the U.S., partly because they are incredibly specific in the habitat they breed in. These birds will only breed in young jack pine forests, with trees that are between 5 to 20 years old. These jack pine trees can be anywhere between 30 to 70 feet tall, and commonly grow bent or twisted.

Jack pines grow in sandy soil, with cones that can remain sealed for years, waiting for a forest fire to revitalize the ground. When the old trees get burnt, their cones burst open, reseeding the ground and allowing a new generation of jack pines to grow.

Conservation Status 

Threats to Conservation

Since Kirtland’s Warblers very specifically breed in young jack pine forests, the lack of fires and thus absence of new generations of trees means that as time goes on, even the conservation of their existing habitats is a threat to their entire species. Kirtland’s Warblers will not nest in jack pine forests that are over 20 years old because as the trees age, higher branches begin to block sunlight from reaching the lower sections that the birds nest in. When the lower branches stop receiving sunlight, they die off, and since the higher parts are too dense for the birds to successfully build nests in, entire populations are left with nowhere to breed.

Some ways to help the Kirtland’s Warbler include controlled burning of old jack pine forests, careful monitoring of currently young forests, and in places where forest burning is unrealistic, manually removing old trees and replacing them.

Funding Opportunities
General Management Guides
Regional Management Guides
Midwest & Central
Resources
Works Cited