Northern Harrier – Circus hudsonius
“The ground nesting Marsh Hawk”
Northern harriers are medium sized birds of prey. The males and females differ based on colorings. Males are gray with black wing-tips while females have speckled brown bodies. Females are also larger than males. All harriers have long and narrow wings, usually held in a V-shape while flying. The wingspan of a northern harrier is roughly 40’’ to 46’’ long. Their tail is also long and slender, with a rounded edge and a white patch on their rump which is clearly visible in flight. Their faces are similar to that of an owl, with a sharply hooked bill and round facial disks that help them hear their prey when hunting.
Northern harriers can be found all across Northern America. They prefer wetland habitats with thick vegetation. Harriers are sensitive to disturbance and thrive in areas that aren’t frequented by humans.
The diet of northern harriers mostly consists of small to medium sized mammals, primarily rodents, as well as birds, reptiles and amphibians. Northern harriers rely on their sense of hearing to locate their prey. When hunting, they can be seen flying in circles, low to the ground. When northern harriers have captured their prey, they typically eat it on the ground.
Northern harriers nest on the ground in open habitats like fields or marshes. They build their nests out of thick-stalked plants like cattails or willows, and conceal their nests with nearby vegetation, helping them blend into the surrounding environment.
Northern harriers breed from April to September, with a peak in June. Breeding habitats range from marshes, meadows, fields, tundras, prairies, and riversides. Preference of habitat tends to be based on geographic location. Western species prefer to breed in dry, upland habitats while Eastern species prefer wet habitats.
Conservation Status
US Conservation Status: Low concern
(Fairly common but their population has been declining by 1% per year since 1966)
(between 700,000 and 130,000 birds in the United States)
Tennessee Conservation Status: In Need of Management
IUCN Status: Least Concern
North American distribution of the Northern Harrier (courtesy of Cornell Lab of Ornithology)
The northern harrier call is a series of “kek” notes that last one to two seconds. This call is performed by both male and females. Females are also known to produce a piercing scream used to attract male attention.