Written by Peter Pearsall/Photos by Dan Streiffert and Peter Pearsall
The Northern harrier (Circus hudsonius) is a commonly encountered bird of prey found across North America, recognizable by its owl-like facial disk and low, gliding flight over open fields and marshes. Sometimes called the “marsh hawk,” harriers are often seen coursing low over the ground in search of small mammals and birds.
The harrier is a medium-sized raptor, with long wings and tail, and a distinctive white rump patch. Males are pale gray above with white underparts, while females and juveniles are brown above with buffy streaked underparts. The owlish facial disk gives the face a flattened appearance, enhancing harriers’ ability to detect prey by sound.
Northern harriers prefer large open spaces—marshes, prairies, fields, and tundra. They breed across the Northern U.S., Canada, and Alaska, primarily in open wetlands and grasslands. Wintering grounds are in the southern U.S., Mexico, and Central America.
Graceful and buoyant on the wing, harriers are often seen flying low in a V-shape profile, with wings held slightly above the horizontal. They use both sight and hearing to locate mammals, small birds, and amphibians.
Harriers are generally quiet, but will call with a series of harsh “kek-kek-kek” sounds during the breeding season. The nest is built on the ground, usually in thick vegetation in marshy or grassy areas. Females lay 4–6 eggs and assume sole incubation duties; males provide food. Male harriers may be polygynous, mating with up to five females in a season and providing prey to them all.
