Hen harrier in England (IN7.8)

The breeding season

Most hen harriers arrive back on their breeding grounds in March or April and the males soon begin to indulge in spectacular, aerobatic display flights in order to attract a female. Aerial displays between paired birds include turning over in flight with talons outstretched, rapid, roller-coaster chases and dramatic stoops towards the ground on folded wings. Some males are polygynous and may be paired’ to as many as six different females in extreme cases. The hen harrier has a strong association with heather in England and nests are almost always sited so that the surrounding heather bushes provide cover and protection. A clutch of 4-6 eggs is laid, usually in May, and incubated mainly by the female for about 30 days.

In flight the hen harrier holds its wings in a shallow ‘V’ giving it a distinctive profile as it quarters low over the ground. Richard Brooks / FLPA

The chicks spend 30-40 days in the nest and are dependent on food brought in by the adult birds until they have learnt to hunt for themselves. The male does the majority of the hunting and transfers food to the female at the nest in a breathtaking display of agility known as the food-pass. This involves the female flying up from the nest and snatching the prey in mid-air with her feet, just after it has been dropped from above by the male.

Although the hen harrier takes a wide range of different prey species, the diet in the breeding season is dominated by small birds and mammals. Voles and meadow pipits are important, particularly early in the breeding season, and skylarks, gamebirds and wader chicks are also taken regularly.

Eggs hatch at regular intervals so there is a substantial size difference between the chicks in a nest. In years when food is short only the largest chicks may survive. Martin Withers / FLPA
ADLib logo Content provided by the Agricultural Document Library
© University of Hertfordshire, 2011