The owl-faced hawk — northern harriers have a flattened facial disk like an owl's to help locate rodents by sound while coursing low over fields. Distinctive low gliding flight with wings held in a "V".
§ Quick facts
§ Encyclopedia
The northern harrier, also known as the marsh hawk or ring-tailed hawk, is a bird of prey. It breeds throughout the northern parts of the Northern Hemisphere in Canada and the northernmost United States.
Source: Wikipedia — Northern harrier Licensed under CC BY-SA 4.0
§ Identification
Field marks. Owl-faced raptor with flat facial disk for sound localization; long wings; white rump patch.
Similar species. Rough-legged Hawk (no flat face, no white rump). Short-eared Owl (round face, owl).
Voice. High whistles; rarely vocalizes.
§ Diet & behavior
Diet. Voles and mice (primary); takes some small birds, amphibians.
Behavior. Coursing low over open marshes and fields with wings held in slight V. Females and juveniles brown; males pale gray with black wingtips ("gray ghost").
§ Range
Throughout North America; breeds in north, winters in south
§ Habitat
Open marshes, grasslands, agricultural fields, prairies
§ Threats
Grassland loss to row-crop expansion, marsh drainage, secondary rodenticide poisoning.
§ Conservation status
According to the IUCN Red List, the northern harrier is currently classified as Least Concern.
§ What helps
Support grassland conservation programs (CRP). Delay haying past July 15. Skip rodenticides.
§ Further reading
- Wikipedia — Northern harrier
- www.allaboutbirds.org — authoritative profile of Circus hudsonius
- IUCN Red List · taxon 22695380
- iNaturalist · taxon 5158
- eBird · norhar2
- GBIF occurrence records
- Encyclopedia of Life — Circus hudsonius
§ Sources cited
- Cornell Lab — All About Birds
- National Audubon Society
- The Peregrine Fund
- IUCN Red List 2016
