Western marsh harrier
The western marsh harrier is a notable bird of prey found primarily in Europe, recognized as the largest member of the harrier family on the continent. Measuring between 19 to 22 inches in length and weighing 14 to 28 ounces, this bird exhibits distinct sexual dimorphism; females have dark brown plumage with a lighter head, while males possess a similar color scheme but feature a gray tail and blue-gray wing patches. Preferring marshes and reedbeds for habitat, the western marsh harrier hunts by flying low and quietly over vegetation, preying on small rodents, amphibians, and other small animals.
Reproduction occurs in the spring, with females constructing platform nests made of reeds and vegetation, where they incubate a clutch of pale blue eggs. Despite facing few natural predators, the species is threatened by habitat loss and pesticide exposure. Some harriers migrate in search of warmer climates during winter, while others remain in their breeding territories year-round. With an average lifespan of six years and a record of 16.5 years, the western marsh harrier is a remarkable species that plays a vital role in its ecosystem.
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Marsh harrier
The marsh harrier is a rare bird of prey in Europe and is the largest of the harrier species in Europe. Like other harriers, it flies low over marshes in search of small rodents, amphibians, birds, fish, and small mammals. It is one of 10 species of harriers in its genus.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Circus
Species: Aeruginosus
The western marsh harrier is 19 to 22 inches (48 and 56 centimeters) long and weighs 14 to 28 ounces (400 to 800 grams). The female's body mainly has dark brown plumage, or feathering, with a lighter-colored head and throat. The male has similar dark brown plumage with a lightly-streaked chest, light head, gray tail, and blue-gray wing patches. Both have yellow legs and feet with strong, sharp talons.
The western marsh harrier lives in marshes and reedbeds. It lives alone except when mating. The harrier flies quietly and low over the vegetation and water looking for a wide variety of food. Because it is so quiet and flaps its wings as little as possible, the harrier can surprise its prey. Small water birds and their eggs, voles and other rodents, frogs, toads, and small mammals, such as rabbits, are all prey of this bird. When it sees a meal, it swoops down and seizes the prey in its talons. Its sharp and strong beak tears quickly and easily into the animal.
In the food chain, the western marsh harrier faces little danger from natural predators. Few animals can catch the harrier. Greater threats to the harrier are the loss of its marsh and reedbed habitats and accidental poisoning. As small creatures in the marsh become poisoned by pesticides and other man-made chemicals, the western marsh harrier becomes poisoned by eating the animals.
A harrier sometimes migrates from the northern part of its range in eastern Europe and Asia where it breeds to western Europe for the winter. At other times, a harrier may migrate to Africa or southern Asia during the winter. If it lives in Madagascar or Australasia it remains there year round.
In the spring and early summer, the male western marsh harrier performs courtship flight patterns to attract a female. After mating, the female builds a large platform nest of reeds, twigs, and other vegetation. She places the nest among the reeds above the water level. She incubates four or five pale blue eggs for 31 to 38 days until they hatch. The male feeds his mate while she sits on the nest to keep the eggs warm. When the chicks first hatch, only the male brings food for them. As the young grow and need more food, the female joins him in hunting. After 30 to 40 days the young fledge, or fly for the first time. They are then called fledglings. For two weeks after they fledge, they receive food from their parents. They reach maturity after three years.
The average lifespan of the western marsh harrier is six years. The record lifespan of a western marsh harrier is 16 1/2 years.
Bibliography
"Marsh Harrier." British Trust for Ornithology, www.bto.org/understanding-birds/birdfacts/marsh-harrier. Accessed 1 May 2024.
"Marsh Harrier." The Wildlife Trusts, www.wildlifetrusts.org/wildlife-explorer/birds/birds-prey/marsh-harrier. Accessed 1 May 2024.