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The animal on the cover of RT Essentials is a northern harrier (Circus cyaneus). Harrier is the common name for 13 species of birds of prey, characterized by long legs, long, broad wings, and an owl-like ruffle of feathers surrounding the face.

Long known as the marsh hawk in the United States and as the hen harrier in England, the northern harrier is the only species of harrier found in North America. A full-grown adult will normally be between 16 and 24 inches in length. The females often grow to be larger than the males.

Northern harriers inhabit open country, primarily marshes and grasslands. They hunt by crisscrossing the area at a low elevation, then dropping on their prey. They feed on small rodents, frogs, snakes, and occasionally birds. In search of prey, the harrier will cover up to 100 miles per day, detecting small animals with its extremely keen hearing.

The northern harrier is considered one of the most agile and acrobatic birds in North America. During the breeding season, the male performs a spectacular courtship flight consisting of a series of U-shaped maneuvers.

Darren Kelly was the production editor, and Julie Campbell was the copyeditor and proofreader for RT Essentials. Jamie Peppard and Colleen Gorman provided ...

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