Western Marsh Harrier vs Montagu's Harrier

In short

The Western Marsh Harrier and Montagu's Harrier are both medium-sized raptors often found in open habitats. The most reliable field mark is the structure and flight pattern: Western Marsh Harriers have broader wings and a heavier build, while Montagu's Harriers are more slender with longer wings and tail. Plumage differences can be subtle, especially in females and juveniles.

Identification tips

1. Structure and flight: Look for the broader wings and heavier build of the Western Marsh Harrier. 2. Plumage: Note the grey and brown contrast in male Western Marsh Harriers versus the uniform grey of Montagu's Harrier males. 3. Habitat: Consider the habitat; Western Marsh Harriers are more likely near wetlands. 4. Flight pattern: Observe the wing position; Western Marsh Harriers hold wings in a 'V', Montagu's Harriers hold them flat.

Size

Western Marsh Harrier is generally larger and bulkier compared to the more slender Montagu's Harrier.

Plumage

Adult male Western Marsh Harriers have a distinctive grey and brown plumage with a pale head, while Montagu's Harrier males are more uniformly grey with black wing tips. Females and juveniles of both species are brown but Western Marsh Harriers tend to have a more pronounced pale crown and throat.

Behaviour

Western Marsh Harriers often glide with wings held in a shallow 'V', whereas Montagu's Harriers have a more buoyant, agile flight with wings held flat.

Habitat

Both species prefer open habitats, but Western Marsh Harriers are more commonly associated with wetlands, while Montagu's Harriers are often found in drier grasslands and agricultural fields.

Voice

Vocalizations are not a primary distinguishing feature in the field; both species are generally silent outside of the breeding season.