White-tailed eagle  (Haliaeetus albicilla)

This impressive bird is the largest European eagle, with huge club-ended wings which make the bright white tail seem small. The head and beak are large and protrude forward, giving the eagle a vulture-like appearance. The feathers are mottled shades of brown, with pale areas on both the upperwing and the underwing. Above the tail the feathers are reddish-brown, and pale stripes run down to the tip of the tail (7).

The largest populations of the white-tailed eagle are found in Norway and Russia, with important populations also found in south-west Greenland, Denmark, Sweden, Poland and Germany. Small numbers can be found in the rest of Europe, the Middle East, China, India and Mongolia (8). It became extinct in Britain in 1916 following excessive shooting, but was reintroduced from 1975 to the Island of Rhum in the Inner Hebrides of Scotland. It can now be found scattered along the west coast of Scotland (7).

Inhabits large, open expanses of lake, coast or river valley in temperate regions and tundra zones. It prefers to be close to undisturbed cliffs or open stands of large, mature trees for nesting (8).

White-tailed eagles are sexually mature at five years old (9). They mate for life, and breed in the same territory each year. These territories continue to be used by successive generations of eagles over many decades (10). One or two chicks hatch each year, and are cared for by both the male and the female. The chicks remain near the nest for some time, until they have learnt to fly and to hunt for themselves (9).

The white-tailed eagle hunts for fish, mammals and birds. It is migratory in the north and east of its breeding range, but sedentary elsewhere (8).

Numbers of white-tailed eagles dropped sharply during the 19th Century and the first half of the 20th Century, and the European range contracted. This trend has been in reverse in the northwest of the range since the 1970s, but it is still in decline in southeast Europe. The continued loss is due to the degradation of wetlands, increasing human disturbance, accidental poisoning, deforestation, and collision with wind generators. It is also susceptible to pollution, accumulating mercury, organochlorine and other pesticides in fatty tissues, which can reduce the breeding success of the white-tailed eagle (8).

A long-term research and nest protection project is underway for the white-tailed eagle, details of which will be kept guarded to prevent disturbance of their habitat. In Hungary, a Species Action Plan has also been published, and the white-tailed eagle is monitored. Many of the white-tailed eagle's breeding grounds are found in protected areas, particularly in Poland, where a large proportion of the population goes to breed. Several countries feed the birds during the winter, and nest guarding is becoming more common. In Latvia, the white-tailed eagle is a protected species, in Israel its habitat in the Hula wetland is being restored, and in Slovakia, artificial nests are being installed (11).

For further information on the white-tailed eagle see:

• BirdLife International:
  www.birdlife.org/datazone/search/species_search.html?action=SpcHTMDetails.asp&sid=3364&m=0
• Hailer, F. (2006) Conservation Genetics of the White-Tailed Eagle. Uppsala University, Sweden. Available at:
  www.diva-portal.org/diva/getDocument?urn_nbn_se_uu_diva-6911-1__fulltext.pdf

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