Henslow’s Sparrow

Ammodramus henslowii

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Photo of a Henslow’s sparrow.
Henslow’s sparrow is small, shy, with a flat-looking, olive-green head. It lives in prairies and other grasslands.
Jim Rathert
Family

Emberizidae (towhees, sparrows, longspurs, buntings) in the order Passeriformes

Description

Adult upperparts are dark brown with black and tan streaks. There is a greenish-gray tint to eyebrow and nape. Crown is dark, with a white central crown stripe and a dark brown, incomplete edge to the greenish cheek. The forehead is low, creating a flat-headed profile with the large bill. Underparts are white, with two dark streaks extending down the neck from the bill and dark streaking on the upper breast. Juveniles lack streaks in the center of the breast. A short-tailed and weak-flying species. Song is an insectlike tsi-lick, or seealick.

Similar species: Sparrow IDs can be tricky. In this case, consider the habitat. Here are two other sparrows to look for in Missouri’s prairies: Grasshopper sparrow has tan cheeks and clear buff underparts, with no streaks on the neck. Le Conte’s sparrow is rarely seen here in summer; it has a broad, orange-buff eyebrow. Dickcissels are somewhat sparrowlike and can be common in prairies, too.

Size

Length: 5 inches (tip of bill to tip of tail).

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Photo of a Henslow’s sparrow.
Henslow’s Sparrow
Henslow’s sparrows arrive in Missouri in spring and remain here to breed. They leave our state by the end of October.

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Photo of a Henslow’s sparrow perched in a prairie composite plant.
Henslow’s Sparrow
Henslow’s sparrow lives in prairies, moist grasslands, alfalfa fields, and weedy fields.

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Photo of a Henslow’s sparrow singing.
Henslow’s Sparrow
The song of the Henslow’s sparrow is a simple, easy to overlook, insectlike song.

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Henslow's Sparrow
Henslow's Sparrow
Henslow’s sparrow is a tiny, four-inch bird weighing less than an ounce that lives reclusively in tall prairie grasses.

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Henslow's Sparrow being measured
Henslow's Sparrow being measured
Henslow’s sparrows are a grassland bird in decline nationally and considered a “species of concern” by the U.S. Fish and Wildlife Service.

Henslow Sparrow

A brown and white bird sits on the end of a branch. It has a piece of nest material in its beak.
Henslow's Sparrow
Henslow's Sparrow
Habitat and conservation

Prairies, moist grasslands, alfalfa fields, and weedy fields. Like the Le Conte’s sparrow, it is shy, reluctant to fly, and requires some effort to get a good look. Listen for its song at dusk and dawn; it sometimes sings at night, too. Compared to the grasshopper sparrow, Henslow’s is more likely to be found in less dry, medium-high to tall grasslands with a 2–3 year accumulation of grass thatch from previous growing seasons. Prefers native prairie and diverse, nonfescue grasslands.

Foods

Forages on the ground, often under grass litter, for seeds and insects.

Distribution in Missouri

Possible to see statewide, but most likely to be seen in our southwestern prairies.

Status

As a summer resident, uncommon and local in southwestern Missouri; rare in the north. In many areas, Henslow’s sparrow populations are declining, undoubtedly because of shrinking grassland habitat. Seven states have declared it endangered within their borders. Conservation organizations and government agencies are working to establish grassland areas large enough to support this and many other prairie species, such as the greater prairie-chicken.

Life cycle

Henslow’s sparrows start arriving here in mid-April. Bowl-shaped nests are constructed of dry grasses, built over the ground on a clump of grass. A clutch comprises 2–5 eggs. In the first half of September, southward migration begins; they are all gone from Missouri by the end of October. The wintering range extends from eastern Texas to the southern tip of North Carolina. Birds that eat seeds off the ground cannot tolerate much snow cover.

Human connections

People tend to like challenges and appreciate the rare. Birders seek out this shy bird with the flat-looking, olive-green head, traveling to our few remaining tallgrass prairies and getting up before dawn to listen for its simple, easy to overlook, yet distinctive, insectlike song.

Ecosystem connections

Tallgrass prairies support a staggering diversity of plants and animals, even within a small section of land. In the past, the central United States was a sea of prairie, but today it’s a sea of agriculture. Henslow’s sparrow is part of the glorious diversity supported in our native grasslands.