Be Your Own Birder

Weekly Bird: Northern Harrier

With behaviors similar to kestrels, facial features similar to owls, and a shape similar to backyard accipiters, this raptor can be a challenge, but when you learn a little more about the northern harrier, you’ll appreciate its uniqueness and distinction even more.

Northern Harrier - Male
Northern Harrier – Male – Photo by Don Owens

Northern Harrier Fun Facts

  • The northern harrier (Circus hudsonius) is a member of the Accipitridae bird family, making it close cousins with the sharp-shinned hawk, Cooper’s hawk, goshawks, sparrowhawks, buzzards, kites, and eagles – more than 240 species make up this diverse raptor family.
  • Other names for the northern harrier include the marsh hawk, grey ghost, hen harrier, American harrier, blue hawk, white-rumped harrier, and frog hawk.
  • The split between the northern harrier of North America and the hen harrier of Europe and Asia is not yet universally recognized, and some ornithological groups still lump the birds together as a single species. More study and evaluation is needed to determine if they are indeed completely separate species.
  • Like owls, northern harriers have a distinctive facial disk that funnels sound to their ears. That keen hearing is essential as they track mice, voles, and similar prey in overgrown fields and pastures, and these raptors rely on hearing just as much as sight, perhaps even more, to find their next meal.
  • While males and females of most raptors look very similar, northern harriers are dimorphic and the two genders are distinctive. Males are light grayish overall, while females are much darker brown. Juveniles resemble females. Both genders show a large, distinctive white rump patch that is useful for identification.
  • These raptors have exceptionally long wings and tails in proportion to their body size – the longest proportions of any raptor in North America.
  • Northern harriers can be somewhat communal outside the breeding season, and will often roost in small groups. Those groups may even include short-eared owls at times. Where prey is particularly abundant, there may be up to 75 or more northern harriers roosting together.
  • An unusual nesting trait of northern harriers is that they nest on the ground, concealing their nesting site in clumps of grass. Unlike many raptors, then, they do not reuse nesting sites from year-to-year.

Adding the Northern Harrier to Your Life List

These raptors can be easy to spot because they hunt over mostly open areas, often staying much lower to the ground than other raptors. Visiting grasslands, marshes, prairies, tundras, pastures, and agricultural fields, especially adjacent to sparse woodland, is the best way to spot northern harriers gliding low above the ground, occasionally hovering as they hunt. They can be active at any time of day, and spotting that bright white rump patch is the key to confident identification, even at a distance. During migration, these raptors are frequently spotted at key hawkwatch sites, and visiting such a site during a count period is a great opportunity to see northern harriers.

Learn More About Northern Harriers

Add to your database of northern harrier knowledge with these resources…

Northern Harrier – Juvenile/Female – Photo by dfaulder

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