Northern harrier
The Northern harrier (Circus hudsonius) is a distinctive bird of prey known for its exceptional hunting skills and migratory behavior. Ranging from 16 to 20 inches in length, this species exhibits sexual dimorphism, with females displaying brown plumage and males exhibiting gray feathering. The Northern harrier primarily inhabits marshes and open country across the northern hemisphere, where it hunts a variety of prey, including rodents, small birds, insects, and even reptiles. Its unique facial structure, reminiscent of owls, enhances its hearing, allowing it to detect prey sounds while flying low over the ground.
During migration, Northern harriers travel individually or in small groups to southern climates, returning to their breeding grounds in late April. The female builds nests in marshy areas or dense vegetation, laying four to eight eggs that she incubates while the male provides food. The chicks fledge about 36 days after hatching and reach maturity within one to three years. Despite facing natural predators such as crows and raccoons, the Northern harrier is not considered a threatened species and can live up to 16 years in undisturbed environments.
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Northern harrier
This bird of prey receives its various names because of where it lives and its hunting habits. Harrier is from an older word, "harrower," which means "something that pursues and destroys." The harrier lives in marshes mostly in the northern hemisphere and hunts a wide variety of small birds and rodents.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Circus
Species: Hudsonius
The northern harrier is around 16 to 20 inches (41 to 52 centimeters) long. The female has brown upperparts, streaked, tan underparts, and black wingtips. The male has gray plumage, or feathering, with a white rump and black wingtips. Males typically weigh between 10 and 14 ounces (290 to 400 grams), while females weigh 14 to 26 ounces (390 to 750 grams). The wingspan of the northern harrier is 38 to 48 inches (97 to 122 centimeters).
The northern harrier is one of 16 species in its genus. These 16 species form a group within the family Accipitridae, one of five families of birds of prey. In North America, this bird is called the northern harrier, while in Europe it is called the hen harrier. Another common name is marsh hawk. Like the other harriers in its genus, the northern harrier is known for its great ability to chase and kill its prey. The name harrier comes from the older word "harrower," meaning "something that pursues and destroys." Some hound dogs which are trained to hunt hares are also called harriers.
Northern harriers are carnivores, or meat-eating birds. The northern harrier has excellent vision and hearing for hunting a wide variety of food during the day. Its main diet includes rodents and small birds, such as larks, sparrows, and quail. It also seizes insects, frogs, snakes, fish, and lizards. The round parts of its face around its eyes are similar to those of owls and help focus even the faintest sounds into the bird's ears. It is able to detect very soft sounds made by its prey and then flies low over the ground or water, surprising the prey with its quiet attack.
All the foods which the northern harrier eats may be found in open country habitats of freshwater or saltwater marshes and dry plains. Sometimes it may settle in the thick vegetation of meadows, damp prairies, and coastal dunes. Northern harriers are at home also in open moorlands and amid young conifer (evergreen) trees. In the fall the harrier migrates along coastal regions of marshes and dunes to southern climates. The harrier usually migrates by itself, but it may join small groups occasionally.
By late April, the northern harrier has migrated again to its breeding grounds in the far northern hemisphere. Mating season lasts until August. Depending on where the harrier lives, the female may build a floating nest on the surface of marsh water or within thick vegetation on the ground of a moor, plain, or grassland. She lays four to eight eggs in the nest and incubates them while the male stands guard. The male brings food for her while she is on the nest and then for her and the young after they hatch. When the male flies near the nest, he calls to the female with a high-pitched "kee-kee-kee," and she then flies up to meet him. She turns onto her back in the air and the male drops the food to her waiting talons. She then eats it herself or feeds the young. The young hatch from their bluish-white shells after 31 to 32 days. After another 36 days they are able to fly for the first time. They are adults when they are one to three years old.
Crows, ravens, owls, feral dogs, raccoons, and skunks may prey on the northern harrier. They may live to be 16 years old if they are left undisturbed in their habitats. They are not a threatened species.
Bibliography
“Northern Harrier - Facts, Diet, Habitat, & Pictures on Animalia.bio.” Animalia, 2024, animalia.bio/northern-harrier. Accessed 1 May 2024.
Polan, Jason. “Northern Harrier - Audubon Field Guide.” National Audubon Society, 2024, www.audubon.org/field-guide/bird/northern-harrier. Accessed 1 May 2024.