Hen Harrier: The Endangered Bird of Prey in the UK

Hen Harrier
Hen Harrier

Hen Harrier; The hen harrier (Circus cyaneus) is a bird of prey that is found in Eurasia. It is known for its distinctive male and female plumages, a long wingspan, and a polygynous mating system. The hen harrier is also known as the northern harrier, and it is a bird of wild places, upland moorland in the summer and coastal marshes during the winter. The bird is affected by both persecution and land management decisions as a breeding bird.

Hen harriers feed mainly on voles and meadow pipits which are found in open areas with low vegetation. In the breeding season, UK birds are to be found on the upland heather moorlands of Wales, Northern England, Northern Ireland and Scotland (as well as the Isle of Man). In winter, they move to lowland farmland, heathland, coastal marshes, fenland and river valleys. The hen harrier is the most intensely persecuted of all the UK’s birds of prey, and it is most at risk on the driven grouse moors of the UK.

Hen Harrier
Hen Harrier

Key Takeaways

  • The hen harrier is a bird of prey that is found in Eurasia and has distinctive male and female plumages, a long wingspan, and a polygynous mating system.
  • Hen harriers feed mainly on voles and meadow pipits which are found in open areas with low vegetation, and they are most at risk on the driven grouse moors of the UK.
  • The bird is affected by both persecution and land management decisions as a breeding bird, and it is the most intensely persecuted of all the UK’s birds of prey.

Identification Features

Plumage

The Hen Harrier is a medium-sized bird of prey with distinctive plumage. Adult males have pale blue-grey upperparts and white underparts, except for the breast which is grey. Their rumps are white, and they have grey wings with conspicuous black wing tips. Their heads are darker grey, and they have yellow eyes and beak, and yellow legs and feet. Female Hen Harriers are larger than males and have brown plumage with white rumps and tails. They also have a distinctive white band across their tails.

Size and Shape

Hen Harriers have a distinctive shape with long wings and a long tail, giving them a ‘V’ shaped appearance in flight. Males have a wingspan of around 97cm, while females have a wingspan of around 120cm. They are around 41-52cm in length and weigh between 300-400g.

Flight Pattern

Hen Harriers are agile fliers and have a distinctive flight pattern. They fly low over the ground, often gliding and hovering, and are capable of sudden changes in direction. They also have a distinctive ‘flap-flap-glide’ pattern of flight.

Overall, the Hen Harrier is a distinctive and easily recognisable bird of prey with unique plumage and flight patterns.

Habitat and Distribution

Hen Harriers are birds of prey that can be found in wild places, upland moorlands during the breeding season, and coastal marshes during the winter. They are distributed across much of the northern hemisphere, from North America to Europe and Asia.

Breeding Habitat

Hen Harriers prefer to nest in open, heather-covered moorland, often near water. They require large areas of suitable habitat to breed successfully. In the UK, they are found mainly in Scotland and parts of northern England, where the habitat is suitable.

Wintering Habitat

During the winter, Hen Harriers can be found in a variety of habitats, including coastal marshes, wetlands, and farmland. They are known to roost communally in dense vegetation, such as reed beds.

Global Distribution

Hen Harriers have a circumpolar distribution, breeding in the northern parts of North America, Europe, and Asia. They are found in a variety of habitats, from tundra to grasslands, but require open areas for hunting. In the UK, the Hen Harrier is a rare and declining species, with only a small breeding population remaining.

Diet and Hunting Behaviour

The Hen Harrier is a bird of prey that primarily feeds on small birds and mammals. They are known to prey on free-ranging fowl, which is how they got their name. According to Animalia.bio, the Hen Harrier breeds in Eurasia and migrates to more southerly areas in winter.

Prey Selection

The Hen Harrier’s diet mainly consists of small birds and mammals, and they are known to prey on red grouse chicks, which can put them into conflict with keepers of managed grouse moors, according to Game and Wildlife Conservation Trust. Additionally, The RSPB Wildlife Charity reports that the Hen Harrier also preys on meadow pipits, skylarks, and small mammals like voles and mice.

Hunting Techniques

The Hen Harrier is known for its distinctive hunting behaviour, which involves flying low over the ground in search of prey. According to GOV.UK, the Hen Harrier’s owl-like facial disk suggests that they hunt using sound as well as vision. They are also known to hover over their prey before swooping down to catch it.

In conclusion, the Hen Harrier is a bird of prey that primarily feeds on small birds and mammals, and it is known for its distinctive hunting behaviour. They are known to prey on red grouse chicks, meadow pipits, skylarks, and small mammals like voles and mice.

Reproduction and Lifespan

Hen Harriers are monogamous birds that mate for life. They begin to breed at two years of age and typically breed once per year, although some may breed twice. The breeding season starts in late March or early April and ends in August.

Breeding Cycle

The female Hen Harrier lays a clutch of 4-6 eggs in a nest made of sticks and twigs on the ground or in a low bush. The eggs are incubated for around 33 days, with the female doing most of the incubation. The male brings food to the female during this time.

Once the chicks hatch, both parents take turns feeding them. The chicks fledge at around 35-40 days old and become independent at around 60-70 days old.

Lifespan and Mortality

Hen Harriers have a lifespan of around 6-10 years in the wild, although some have been known to live up to 16 years. Mortality is highest in the first year of life, with around 70% of chicks dying before they reach their first birthday.

Adult Hen Harriers are at risk from illegal persecution, particularly on grouse moors, where they are seen as a threat to game birds. They are also at risk from habitat loss and degradation, as well as collisions with vehicles and wind turbines.

Conservation Status

Hen harriers are a bird of prey that are classified in the UK as “Red” under the Birds of Conservation Concern 5: the Red List for Birds (2021) The Wildlife Trusts. This means that they are considered to be of the highest conservation priority. The main threats to hen harriers are illegal persecution, habitat loss and fragmentation, and disturbance BTO – British Trust for Ornithology.

Threats

Hen harriers are the most persecuted bird of prey in the UK. They are often illegally killed by gamekeepers on grouse moors, as they are seen as a threat to red grouse, which are hunted for sport. This illegal persecution has resulted in a significant decline in hen harrier numbers The RSPB Wildlife Charity.

Habitat loss and fragmentation are also major threats to hen harriers. They require large areas of open moorland for breeding, and the loss of this habitat due to afforestation, agricultural intensification, and urbanisation has led to declines in their population. Disturbance, particularly during the breeding season, can also have a negative impact on hen harriers The Wildlife Trusts.

Conservation Efforts

Conservation efforts for hen harriers include monitoring, habitat management, and legal protection. The UK government has implemented measures to protect hen harriers, including the Wildlife and Countryside Act 1981, which makes it illegal to kill or injure hen harriers or damage their nests GOV.UK.

Natural England has also been tagging and tracking hen harriers to monitor their movements and identify areas where they are at risk. This information is used to inform conservation efforts and target resources to areas where they are needed most Natural England.

Habitat management is also important for hen harrier conservation. This includes maintaining open moorland habitat and promoting sustainable land use practices that benefit both hen harriers and other wildlife BTO – British Trust for Ornithology.

Overall, conservation efforts for hen harriers are ongoing, and it is hoped that these measures will help to secure the future of this iconic bird of prey.

Hen Harrier and Human Interaction

Cultural Significance

The Hen Harrier is a bird of prey that has cultural significance in many parts of the world. In the UK, it is considered a symbol of the uplands and is an important part of the country’s cultural heritage. The bird is also known as the “Skydancer” due to its distinctive aerial courtship display. This display involves the male bird performing a series of acrobatic manoeuvres, including rolling and diving, to impress the female.

Conflict and Resolution

Despite its cultural significance, the Hen Harrier has been the subject of conflict between conservationists and gamekeepers. This conflict arises because the bird preys on red grouse, which are reared for shooting on moorlands. Gamekeepers often view the bird as a threat to their livelihoods and have been known to illegally kill them.

Conservationists, on the other hand, argue that the Hen Harrier is a protected species and that its numbers are in decline due to human persecution. They believe that the bird should be allowed to thrive in its natural habitat and that measures should be taken to prevent illegal killing.

Efforts have been made to resolve this conflict through initiatives such as the Hen Harrier Action Plan, which aims to increase the bird’s population while also ensuring that grouse shooting can continue sustainably. The plan involves measures such as monitoring bird numbers, providing alternative food sources for the birds, and improving habitat management.

Overall, the conflict between conservationists and gamekeepers over the Hen Harrier highlights the need for sustainable management of the UK’s uplands. By working together, it is possible to ensure that both the bird and the livelihoods of those who live and work in the uplands can be protected for generations to come.

Frequently Asked Questions

What is the size of a juvenile Hen Harrier?

Juvenile Hen Harriers are slightly smaller than adults, with a wingspan of around 90cm and a length of 41-45cm. They also have a different plumage than adults, with brown feathers and a streaked appearance.

What is the population of Hen Harriers in the UK?

The population of Hen Harriers in the UK is estimated to be around 600 breeding pairs, with a concentration in Scotland and Northern England. However, this number is much lower than it should be due to illegal persecution.

What is the name of a female Hen Harrier?

The female Hen Harrier is known as a “hen harrier” or a “ringtail” due to her distinctive white rump and tail feathers, which are banded with black.

How can Hen Harriers be identified?

Hen Harriers can be identified by their distinctive flight pattern, with deep and powerful wingbeats interspersed with gliding. They also have a distinctive white rump patch, with males having a pale grey plumage and females having a brown plumage.

What prey do Hen Harriers hunt?

Hen Harriers primarily hunt small mammals such as voles and mice, as well as small birds such as meadow pipits. During the breeding season, they may also take larger prey such as rabbits and hares to feed their young.

Why are Hen Harriers shot by people?

Unfortunately, Hen Harriers are often shot by people due to conflicts with game shooting interests. This illegal persecution has led to a decline in the population of Hen Harriers in the UK, and is a serious threat to their survival.

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