Northern Harrier

Circus cyaneus

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Photo of a northern harrier in flight, viewed from side
The northern harrier is a hawk of wetlands and grasslands. It has long wings and tail, a white rump patch, and an owl-like facial disk.
Noppadol Paothong
Endangered
Species of Conservation Concern
Other Common Name
Marsh Hawk; Harrier Hawk
Family

Accipitridae (hawks and eagles) in the order Falconiformes

Description

Adult northern harriers have long wings and tail, a white rump patch, and an owl-like facial disk. The female is brown and streaked below; the male is gray above and white below; in flight, from below, the male's whitish body contrasts with black wingtips and black trailing edge to wings. Immatures are similar to the adult female but are darker chestnut-colored on the breast and belly and are streaked only on the breast. The flight pattern is distinctive: gliding low over the ground, wings held in a shallow V, with buoyant, nimble, tilting movements. Calls include high whistles and barks.

Similar species: The various buteo hawks are larger, chunkier, with wider, more rounded wings and shorter tails. Although both turkey vultures and rough-legged hawks share the habit of flying with wings in a V-shape, neither flies low over the ground like the northern harrier. Cooper’s and sharp-shinned hawks have long tails, but their wings are shorter and rounder; also, they aren’t common in grasslands. The northern goshawk is gray, but lacks the white rump patch, and like the Cooper’s, it doesn’t fly slowly over the ground.

Size

Length: 18–22 inches; wingspan: 40–47 inches.

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Photo of a male northern harrier standing on the ground
Northern Harrier (Male)
The adult male northern harrier is gray above and white below.

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Photo of a juvenile northern harrier standing on the ground
Northern Harrier (Juvenile)
Juvenile northern harriers are similar to the adult female but are darker chestnut-colored on the breast and belly and are streaked only on the breast.

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Photo of a female northern harrier standing on the ground
Northern Harrier Female
Female northern harriers are brown and streaked below.

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Photo of a male northern harrier with wing upraised
Northern Harrier Male
Male northern harriers, from below, show dark wing tips and dark trailing edge to wings.

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Photo of a juvenile northern harrier flying, seen from below
Northern Harrier Juvenile
From below, juvenile northern harriers are chestnut-colored on the breast and belly and lack streaking on the belly.

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Photo of a female northern harrier flying low over a field
Northern Harrier Female
Female northern harriers have a streaked belly.

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Photo of a female northern harrier in flight, seen from behind
Northern Harrier Female
Northern harriers typically hold their wings in a shallow V shape. There is a conspicuous white rump patch.

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Photo of a juvenile northern harrier just above ground, reaching to grasp something with its feet
Northern Harrier Juvenile
The northern harrier's common name is a form of the word harrower, which means “pillager” or “plunderer.”

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Photo of a male northern harrier in flight, grasping something with its feet
Northern Harrier Male
Northern harriers hover over one spot, then plunge feet-first into the vegetation to capture prey.

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Photo of a northern harrier in flight, seen from side
Northern Harrier
Northern harriers could be confused with short-eared owls; both live in grasslands and both have a graceful mothlike flight and circular faces.

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Photo of a male northern harrier pursuing a greater prairie-chicken cock
Northern Harrier and Greater Prairie-Chicken
Northern harriers forage in open areas for rodents, birds, snakes, and insects.

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Photo of a male northern harrier pursuing a greater prairie-chicken hen
Northern Harrier and Greater Prairie-Chicken Hen
Northern harriers are nimble, graceful fliers that use their impressive agility to capture birds and other prey.

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Photo of a male and female northern harrier in flight, seen from behind
Northern Harriers in Flight
In Missouri, northern harriers are a rare and local summer breeding resident in extensive grassland landscapes.
Habitat and conservation

Northern harriers are usually seen over prairies, marshes, and hay fields as they forage with their distinctive flight pattern, gliding slowly across the open areas, wings raised in a shallow V like a turkey vulture’s. The common name is a form of the word harrower, which means “pillager” or “plunderer.” From the perspective of their prey, that would aptly describe this hawk’s attack from above.

Foods

Northern harriers forage in open areas for rodents, birds, snakes, and insects. They fly over fields within a few yards of the ground, listening for their prey moving in the grass below. They hover over one spot, and plunge feet-first into the vegetation to capture prey. This species, and Swainson’s hawk, are most likely to appear at grassland or crop stubble fires during the spring and fall, when they can be seen preying on animals fleeing the fire. The smoke from distant fires often attracts raptors, especially these two species.

Distribution in Missouri

Statewide. In winter, more common in southern Missouri than in the north.

Status

Endangered within Missouri; in peril of extirpation within our borders; a Species of Conservation Concern. Uncommon migrant seen in prairies, marshes, and hay fields. Uncommon winter resident. Rare and local summer resident in extensive grassland landscapes. Northern harriers occur across North America and Eurasia.

Life cycle

Populations in Missouri peak during migration: from late February through the end of April, and from mid-September through the end of November. The winter territory for North American harriers includes Missouri and areas south, into northern South America. Nests are built on the ground, usually in dense, low vegetation, and are platforms made from the thick plant stalks and lined with finer grasses. Clutches comprise 4–5 eggs, which are incubated for about a month. Two weeks after hatching, the young are ready to leave the nest. There is only 1 brood a year. Northern harriers can live to be at least 15 years old.

Human connections

Harriers are nimble, graceful fliers and are a pleasure to watch. Harrier populations have been declining steadily in the last 50 years, mainly due to human actions upon the environment: loss of habitat (draining of wetlands, large-scale agriculture, and so on), reduction of prey animal populations (a result of eradication efforts and large-scale agriculture), and eating poisoned animals.

Ecosystem connections

Both the northern harrier and owls have round faces encircled by stiff facial feathers. This adaptation functions like a sonar disk by channeling sound waves to their ears. Thus it helps these predatory birds hear the rustlings of prey concealed beneath vegetation. Though both harriers and owls share this adaptation, they are not related. Most other hawks rely mainly on sight to locate prey.