The white-tailed sea eagle, a large bird of prey, can be found across temperate regions of Eurasia. Part of the Accipitridae family, this eagle shares its lineage with other diurnal raptors, including hawks and harriers.
Key Facts About the White-Tailed Sea Eagle
- Scientific name: Haliaeetus albicilla
- Weight: 4.02 – 5.11 kg (8.9 – 11.3 lb)
- Length: 66 to 94 cm (26 to 37 inches)
- Wingspan: 1.78 – 2.45 m (5 feet 10 inches – 8 feet)
- Average lifespan: 12 years
- Diet: Fish, birds, mammals, and other prey
1. Classification
The white-tailed sea eagle is notable for its strong beak, muscular legs, and sharp talons, enabling it to capture prey from considerable distances. Its excellent eyesight is attributed to its large pupils, which enhance its hunting precision.
2. Identification
Ranked as the fourth-largest bird of prey, this eagle has an impressive wingspan, often likened to a “flying barn door.” Adults are recognized by their white tail and pale head, while juveniles, which don’t reach full plumage until age eight, have a brown tail edged with white and a mottled appearance.
3. Sexual Dimorphism
Female white-tailed sea eagles are typically larger, weighing up to 25% more than males. This size difference may reduce the risk of males posing a threat during courtship, which can sometimes involve aggressive behaviors.
4. Habitat and Range
White-tailed sea eagles inhabit northern and central Europe, particularly in coastal and freshwater regions. While adults in central Europe are mostly stationary, those from northern areas migrate seasonally. Juveniles are more mobile, often dispersing from their birth sites earlier than adults.
5. Diet and Hunting Methods
These eagles primarily feed on fish, especially pike, and on various bird species. Though capable of catching larger prey, they typically target smaller or vulnerable animals, using trees or cliffs as vantage points for hunting. In regions like Norway, common eiders are a significant part of their diet.
6. Courtship and Nesting
White-tailed sea eagles are monogamous, staying with one mate at a time but quickly finding another if a partner dies. Courtship, including dramatic displays known as “sky-dancing,” generally occurs in spring.
Nests, often built in large trees or cliffs, are reused for years and located close to food sources. Each breeding season, pairs lay two to three eggs, and young eagles begin flying by 70 days old, reaching maturity around five to six years.
7. Historical Challenges
Historically, white-tailed sea eagles faced severe persecution, particularly in Western Europe, due to perceived threats to livestock and game. Additionally, widespread DDT use in the 1950s significantly impacted their reproduction, as the pesticide caused thin eggshells, leading to crushed eggs.
By the early 1900s, they were extinct in the British Isles and eventually disappeared from much of Western Europe, except for parts of Scandinavia.
8. Conservation Efforts
Conservation initiatives began in Sweden with supplemental feeding programs to reduce DDT exposure. Today, protective measures across Europe have helped stabilize their populations. In Norway alone, there are now an estimated 3,600 pairs.
Reintroduction efforts in the British Isles began in 1975 on the Isle of Rum, Scotland, and recently, young eagles were reintroduced to the Isle of Wight, with encouraging results as the population rebuilds in England.
Through a combination of legal protections and reintroduction programs, the white-tailed sea eagle is once again flourishing in many parts of Europe, embodying a conservation success story.
Read More Birds