Birdsong field guide
Western Marsh Harrier
Circus aeruginosus
A large, robust raptor of the harrier family, characterized by its slow, buoyant flight over wetland ecosystems.
What it sounds like
A thin, nasal 'kee-yee' given by the male during courtship, and a high-pitched, repetitive 'pi-pi-pi' from the female.
Field notes
- Exhibits strong sexual dimorphism: males have tricolored wings of grey, black, and brown, while females are chocolate-brown with distinctive cream-colored crowns.
- Unlike most other hawks, this species typically nests on the ground within dense reedbeds to protect its young from terrestrial predators.
- It employs a characteristic 'dihedral' wing position, flying low over vegetation to surprise prey using its keen sense of hearing and sight.
- Male marsh harriers perform elaborate 'sky-dancing' aerial displays during courtship, involving dramatic stalls, tumbles, and mid-air rolls.
- It is the largest and heaviest species among the harriers, often outcompeting smaller relatives for prime wetland hunting grounds.
Habitat
Extensive reedbeds, freshwater marshes, fens, and occasionally coastal saltmarshes or cereal crops.
Range
Widespread across Europe and Central Asia, with migratory populations wintering in Sub-Saharan Africa and South Asia.
Similar & commonly confused birds
Heard a Western Marsh Harrier?
Open Birdsong, tap record, and identify the bird singing near you in seconds — then collect it in your field journal.
Identify a bird by its song