Hen Harrier vs Montagu's Harrier
Circus cyaneus and Circus pygargus
Montagu's Harrier
Circus pygargus
Comparison notes
Field marks and practical differences
Hen Harriers and Montagu’s Harriers are both slender raptors that can be challenging to distinguish in the field, especially females and juveniles. Male Hen Harriers are pale grey with black wing tips and a distinctive white patch on the lower back, while females and juveniles are brown with a clear white lower back patch and a barred tail. Montagu’s Harrier males are also pale grey but have a single black bar across the wings, and females show streaked brown plumage with a paler lower back patch. Hen Harriers tend to have broader wings and a more steady, shallow V-shaped wing posture in flight, whereas Montagu’s are smaller, lighter, and display a more buoyant, tilting flight often including brief hovering. Habitat and seasonal presence also aid identification. Hen Harriers breed mainly on upland moorlands and move to lowland marshes and farmland in winter. Montagu’s Harriers are summer visitors, breeding locally in farmland, young pine forests, and heathland. Their hunting styles differ too: Hen Harriers fly low with steady wingbeats scanning for small mammals and birds, while Montagu’s use a distinctive back-and-forth tilting flight, often hunting insects as well as small vertebrates.
Size stats
Compare species by wingspan and weight
- Body length
- 40 - 52 cm
- Wingspan
- 97 - 122 cm
- Weight
- 290 - 450 g
- Body length
- 40 - 48 cm
- Wingspan
- 97 - 120 cm
- Weight
- 250 - 350 g
Habitats
Where they live
Diet breakdown
What they eat
- Vertebrates80%
- Insects15%
- Other Invertebrates5%
- Vertebrates50%
- Insects40%
- Other Invertebrates10%
Species notes
Descriptions and photographer notes
Hen Harrier
The Hen Harrier is a medium-sized bird of prey that looks very different between males and females. Males have pale grey feathers on their backs with black tips on their wings and a white patch on their lower back. Females and young birds are brown with a clear white patch on their lower back and a striped tail. Both males and females fly low over open land with a light, steady wingbeat, holding their wings in a shallow V shape. In the UK, Hen Harriers mainly breed on upland heather moorlands in northern England, Scotland, Wales, and Northern Ireland. However, their numbers have dropped significantly because they have been hunted. In winter, they move to lower areas like coastal marshes, farmland, and young forests. They hunt small animals like mice and ground-nesting birds, often catching their prey by flying low and searching carefully across open land.
Montagu's Harrier
Montagu's Harrier is Britain's rarest breeding harrier. It is a slender, graceful bird of prey that lives in open countryside. The males are easy to recognise because they have pale grey feathers, black wingtips, and a single black bar across the middle of their wings. Females and young birds are brown with streaks and have a pale patch on their lower back. This bird is smaller and lighter than the Hen Harrier, with narrower wings and a more buoyant flight. Montagu's Harrier visits the UK in the summer, from April to September. However, there are only a few places where it breeds, and these are quite localised. It prefers farmland with crops, young pine forests, and heathland for nesting. The bird is more common in mainland Europe, especially in France and Spain. It hunts by flying low over grasses and reed, using a distinctive tilting flight. It moves back and forth carefully, looking for small birds, voles, and large insects. The harrier is often seen hovering briefly before swooping down to catch its prey.