Hen Harrier: where and when to see them

The hen harrier is a long-winged raptor of open landscapes, known for its low, buoyant hunting flight. Scotland supports an important breeding population, although persecution and habitat pressures affect its fortunes. Adult males are pale grey, while females and young birds are brown with a conspicuous white rump. Its global assessment does not reflect the seriousness of regional conservation problems or the vulnerability of individual nesting areas.

Size

44-52 cm long; 100-120 cm wingspan

Weight

300-600 g

Lifespan

Not reliably established

Status

Least Concern

Hunting birds quarter moorland or rough grassland with wings held in a shallow V, turning repeatedly to investigate movement below. They use both hearing and sight to locate prey hidden in vegetation. Breeding males perform spectacular rolling display flights and may pass food to females in midair. Outside the breeding season, several birds can gather at communal ground roosts, where disturbance is especially costly during cold weather. The male's 'sky dance' involves a series of dramatic dives and tumbles, performed to attract a mate and establish territory. During winter, they often form communal roosts at night, sometimes gathering dozens of individuals for safety and warmth.

• Females are substantially larger than males.
• The facial ruff helps direct sound toward the ears.
• Males can provision more than one nesting female.
• Brown females and juveniles are often collectively called ringtails.

Winter is particularly useful for coastal observation, when harriers may hunt marshes and rough grassland or gather near communal roosts. Spring and summer bring breeding activity inland, but nesting locations are sensitive and should never be sought by leaving established routes. Prime viewing opportunities from deck often occur during migration periods or when birds are foraging over coastal wetlands visible from the ship. Shore excursions to coastal reserves in winter may offer reliable sightings as they congregate at roosts.

Breeding habitat in Scotland includes heather moorland, young forestry and rough upland vegetation with ground cover for nesting. In winter, birds also use lowland marshes, coastal grassland, reedbeds and farmland. Sheltered coastal wetlands can therefore offer viewing without entering breeding moors. Though often associated with remote uplands, they can also forage over lowland agricultural areas and coastal fringes when not breeding. They require large, undisturbed tracts of habitat, making them vulnerable to fragmentation and development.

Small mammals and birds form the bulk of the diet, with proportions changing between habitats and seasons. Voles are important where abundant, while meadow pipits and other small birds feature in upland diets. Most prey is captured on or near the ground. Occasionally, they will also take carrion, especially during harsh winter conditions or when live prey is scarce. Their hunting success rate is influenced by prey density and vegetation cover.

Common name

Hen Harrier

Scientific name

Circus cyaneus

Animal group

Birds

Size

44-52 cm long; 100-120 cm wingspan

Weight

300-600 g

Lifespan

Not reliably established

Status

Least Concern

Identification

Compared with Montagu's harrier, hen harriers are broader-winged and heavier-looking, with adult males lacking Montagu's distinct black wing bars and brown birds showing a broad white rump. Adult males are distinctive with their pale grey plumage, black wingtips, and white underparts, earning them the nickname 'ghost of the moor'. Females and juveniles are brown above with streaked underparts and a prominent white rump, often referred to as 'ringtails'.