Thursday, February 12, 2009

Northern Harrier--Circus cyaneus

Female Harrier on the ground at Upper Newport Bay Ecological Reserve aka Newport Back Bay . Notice her brown coloring.

Northern Harriers used to be called Marsh Hawks when I started birding in the early 1980s. In Europe, the Northern Harrier is called the Hen Harrier.  Harrier means hunter.  The Northern Harrier hunts by sight and sound. It has a facial disk similar to an owl and serves the same purpose. The facial disk directs sound to the Harrier's ears.

Female Northern Harrier with white rump visible--can you see it?
Because it hunts by sound as well as sight, the Northern Harrier flies low over the wetlands or marsh from as low as 5 feet, although sometimes much higher. The most obvious field mark is its white rump.   It is possible to see it soaring high above the ground, but not common.  Usually, you will spot the Northern Harrier as it flies low over the ground and you spot the white rump.

Female Norther Harrier at San Jacinto Wildlife Area

Although male and female are quite different, both have the distinctive white rump and forage by flying low over ground. Their flight, too, is distinctive with rapid wing beats alternating with gliding giving them what some call a "roller coaster" type of flight.

Female Northern Harrier on the ground at Upper Newport Bay Ecological Reserve aka Newport Back Bay . Notice the facial disk--very owl-like.

Northern Harriers also often rest on the ground like the female in the picture above or in foliage low to the ground like the female below.   Females are bigger than males and hunt in slightly different area--those with higher grass.

Female Northern Harrier in the brush at San Jacinto Wildlife Area

If a male and female get into a confrontation, the larger female is the winner. So she hunts where she chooses. The male is very different in appearance from the female Northern Harrier. Most hawks differ mostly in size, but not in color. 

Male Northern Harrier at Fairview Park in Costa Mesa

However, the Northern Harrier female is brown and white, and the male Northern Harrier is gray and white. Both have a white rump and fly low over the ground. Juvenile Northern Harriers look similar to females but may be darker and have streaking or barring on the stomach and chest. Full adult plumage may take 3 years or more.

Female Norther Harrier on a tree stump out in the wetlands at Upper Newport Bay. Notice the very long legs.

Blurry thought it is, this picture shows something about Northern Harriers that is worthy of note. It has very long legs. Even in flight they hang down. When they stand in the tall grass or other marsh foliage, the legs are pretty hard to see.   However, in the picture above the Harrier's long legs can easily be seen as it perches on a tree stump.

Male Northern Harrier flying low over the water. Notice his gray and white coloring. Notice that his long legs hanging down.

Female Northern Harrier flying over field at San Jacinto Wildlife Area in San Jacinto

Northern Harrier males have 2-3 female mates at the same time. They nest on the ground and vigorously defend their nests against any potential predator including people. The male Northern Harrier is busy during nesting season bringing food to all his mates and their offspring.

Northern Harriers eat rodents and other mammals, birds, reptiles, insects, and occasionally, carrion. Some of the birds harriers eat can be large. Like ducks and shorebirds like American Avocets. The Northern Harrier sometimes drowns larger birds.

This Northern Harrier female courtesy of US Fish and Wildlife Service.   Photographer Kent Olson.

Northern Harriers hunt in wetlands, fields, pastures, and grasslands. Basically, open areas with plants that may attract prey. They may fly low over the ground or hover. Like the Turkey Vulture which flies much higher, the Northern Harrier holds its wings at a slight dihedral. Their white rumps are often visible as they fly across the wetlands or other open areas hunting. They frequently scatter large groups of birds as they fly past them just a few feet above their heads. When you see a lot of shore birds scattering in a panic, check low to the ground and you may see this hawk.

Northern Harrier female in flight courtesy of  Wiki Commons.  Photographer is Dan Pancamo.

The Northern Harrier can be found in North America in Alaska, Canada, and down into California. They can also be found in Central and a little bit of South America. They are also found in Europe (where they are called Hen Harriers), the Middle East, to Asia and in bits of Northern Africa.

Very good video of a Northern Harrier female hunting in England. Posted on You-Tube

The Northern Harrier has been seen at Fairview Park in Costa Mesa, Talbert Regional Park, Banning Ranch, Upper Newport Bay, San Joaquin Wildlife Sanctuary in Irvine, The UCI San Joaquin Marsh Reserve, The Great Park, Crystal Cove, State Park, and Bolsa Chica Ecological Reserve in Huntington Beach (and the adjoining parks like Harriett M. Wieder Regional Park), and all the small wetlands along PCH in Huntington Beach.  Check out wetlands and rivers (Especially the Santa Ana River) near you for the Northern Harrier, and have fun birding in Orange County!

OC Birder Girl Links

Bolsa Chica Ecological Reserve

Upper Newport Bay Ecological Reserve aka Newport Back Bay

San Joaquin Wildlife Sanctuary

Red-Tailed Hawk

Cooper's Hawk

Red-Shouldered Hawk

American Kestrel--Falco sparverius

White-Tailed Kite--Elanus leucurus

Great Horned Owl--Bubo virginianus

Barn Owl--Tyto alba

External Links and Resources

All About Birds: Northern Harrier

Detailed page about the Northern Harrier from Cornell University Ornithology Lab.

Animal Diversity Web: Northern Harrier

Detailed article with photographs about the Northern Harrier.

BirdWeb: Northern Harrier

Seattle Audubon page on the Norther Harrier. Good information.

Desert USA: Northern Harrier

Good, short article on the Northern Harrier.

Internet Bird Collection: Hen Harrier

The European name for Northern Harrier is Hen Harrier. Great group of videos. High quality.

Southern Adirondack Audubon: Identifying Northern Harriers, Rough-legged Hawks and Short-eared Owls

Great article with photos on differentiating the three species and male and female Northern Harrier.

Northern Harrier Casts Pellet While in Flight

By Mark A. Manske (Journal of Raptor Research: Vol. 24, No. 3, 1990) from SORA.

Peregrine Fund: Northern Harrier

Short, but helpful article about the Northern Harrier.


By ETHAN J. TEMELES (Auk: Vol. 103, No. 1, January-March, 1986) from SORA.

Techniques for Differentiating Pellets of Short-Eared Owls and Northern harriers

By Denver W. Holt, L. Jack Lyon, and Robert Hale (Condor: Vol. 89, No. 4, July-August, 1987) from SORA.

USGS: Northern Harrier

Short, but helpful article about the Norther Harrier from the USGS--includes pictures.

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