Species Profile
Western Marsh-harrier
Circus aeruginosus
Quick Facts
Conservation
LCLeast ConcernAlso known as: Eurasian Marsh-harrier, Marsh Harrier, Western Marsh Harrier
Think you've spotted a Western Marsh-harrier?
Upload a photo and our AI will confirm it instantly
Confirm with a PhotoGallery
Appearance
The Western Marsh-harrier is a large raptor with long, broad wings and a long tail. Males have a distinctive tricoloured plumage: grey head and wings, reddish-brown body, and black wingtips. Their eyes and legs are yellow.
Females are predominantly dark brown with a cream-coloured crown, throat, and leading edge of the wings. They're also about five percent larger than males on average. Juveniles resemble females but are darker overall with less contrasting head markings.
Identification & Characteristics
Male Colors
- Primary
- Brown
- Secondary
- Buff
- Beak
- Black
- Legs
- Yellow
Female Colors
- Primary
- Brown
- Secondary
- Buff
- Beak
- Black
- Legs
- Yellow
Female Markings
Cream-colored crown and throat
Attributes
Understanding Attributes
Rated 0–100 based on research and observation. A score of 50 is average across all bird species. These attributes are relative and don't necessarily indicate superiority.
Habitat & Distribution
Western Marsh-harriers inhabit wetlands, including marshes, reedbeds, and wet grasslands across Europe, Asia, and parts of Africa. They prefer lowland areas with dense vegetation near water bodies.
In the UK, they are found primarily in eastern and southern England, with some populations in Wales and Scotland. During winter, many European birds migrate to Africa, while others move to coastal areas.
RSPB Minsmere in Suffolk is an excellent place to look for Marsh Harriers, although visiting other reedbed habitats in East Anglia may be rewarding. Somerset in the Southwest is also a good part of the country to look for Marsh Harriers.
Distribution
Where to See This Bird
Explore regional guides for locations where this bird has been recorded.
Cambridgeshire
United Kingdom
Rutland
England
Cheshire
Dorset
East Riding of Yorkshire
Essex
East Sussex
Gloucestershire
Hampshire
Isle of Wight
Kent
Merseyside
Lancashire
Lincolnshire
Northumberland
Norfolk
Oxfordshire
South Yorkshire
Suffolk
Somerset
Stockton-on-Tees
West Yorkshire
West Sussex
Diet
Western Marsh-harriers are opportunistic hunters, preying on small mammals, birds, reptiles, amphibians, and large insects. Birds up to the size of gulls and ducks are their most frequent prey. They also feed on carrion when available.
They often hunt by flying low over reedbeds and suddenly dropping onto their prey, sometimes wading into shallow water to catch fish.
Behaviour
Western Marsh-harriers are known for their low, slow flight over reedbeds and marshes, often tilting from side to side as they search for prey.
They are generally solitary but may gather in small groups during migration or at communal roosts.
Calls & Sounds
Western Marsh-harriers are generally quiet outside the breeding season. During breeding, they produce a series of sharp, nasal 'kek-kek-kek' calls. Males may also emit a high-pitched whistle during courtship displays, sometimes described as a 'pee-oo' sound. They also produce a cackling alarm call when threatened.
Nesting & Breeding
Breeding season for Western Marsh-harriers typically begins in April. Males perform spectacular aerial displays to attract females, including steep climbs and dives.
Nests are built on the ground or in dense vegetation, usually in reedbeds or marshes. They are constructed of reeds, grass, and small branches. Females lay 3-8 pale blue eggs.
Incubation lasts about 31-38 days, primarily done by the female. Chicks fledge after 35-40 days but remain dependent on parents for several more weeks.
Conservation
While currently listed as Least Concern globally, Western Marsh-harriers face threats from habitat loss, drainage of wetlands, and persecution. Conservation efforts focus on protecting and restoring wetland habitats, particularly in their breeding areas.
Marsh Harriers went extinct in Britain in the 1800s, and the current population grew from just one pair at the start of the 1970s. Today, there may be as many as 600 pairs, and they are not considered endangered. However, The species remains on the UK's amber list of conservation concern.
Birdwatching Tips
- Look for their distinctive low, quartering flight over wetlands and reedbeds
- Listen for their 'kek-kek-kek' call during breeding season
- Observe them in early morning or late afternoon when they're most active
- In the UK, visit coastal marshes and wetland reserves for the best chances of spotting them
- They're similar to the Buzzard but have a much ganglier look and are typically seen flying low over marshlands with their wings held in a characteristic v-shape.
Did You Know?
- Western Marsh-harriers can hunt cooperatively, with one bird flushing prey for another to catch.
- They are one of the few raptors that practice polygyny, with males sometimes mating with multiple females.
- In the UK, they were once extinct as a breeding species but have made a remarkable comeback since the 1970s.
Community Photos
Be the first to share a photo of the Western Marsh-harrier
Upload a PhotoSimilar Species
Related Articles
Identify Any Bird Instantly
- Upload a photo from your phone or camera
- Get an instant AI identification
- Ask follow-up questions about the bird
Monthly Birds in Your Area
- Personalised for your location
- Seasonal tips and garden advice
- Updated every month with new species