The Northern Harrier

The Northern Harrier, Circus hudsonius, is a species of raptor which inhabits both inland and coastal marshlands. When I first started birding back in the late 1960’s, it was called the Marsh Hawk, Circus cyaneus. This bird could be seen flying low over marshes or fields with a very distinctive dihedral and the white rump made it stand out. All three stages of this species, ages and sex, have different color plumages.

The male has a gray back, head and upper breast and the rest of the breast and underwings is white, with rufous spotting in the white breast and dark ends to the primaries and secondaries.

The female is completely different. Her plumage is basically brown where the male is gray, and the barring on the upper and under view of the wings are significantly more noticeable. The breast is somewhat creamy below, with longitudinal streaking.

The immature bird is different from both adults’ plumages. It is most similar to the female with respect to the dorsal coloration being brown and the same type of wing and tail markings, but the breast is completely different. The breast of the immature Northern Harrier is uniform rufous in Fall and creamy in Spring.

Now this species was considered conspecific with the Hen Harrier, Circus cyaneus, of Eurasia. So, in 1982, the American Ornithologist Union changed the name of Marsh Hawk to Northern Harrier. Some European ornithologists did as well, but many kept the common name Hen Harrier.