In the genus surnia the form is stout, but larger and more hawk-like than nyctea; the wings and tail are long, and the legs rather short. It is found in the northern regions of both hemispheres, it is common in the fur countries, where it is often seen hunting by day, approaching the camps with great boldness. In summer it feeds on squirrels, mice, and insects, and in winter principally on the ptarmigan and grouse. This bird approximates to the falcons in its bold and diurnal habits, and in the absence of facial disk and ear tufts, smaller size of the head, smaller eyes, and less developed ears; its eyes are adapted for the dim light of snow-clad and arctic regions. The birds of this form inhabiting Northern Europe and the northern parts of America have been regarded as identical, in which case the genus would consist of a single species ; but some have endeavoured to show that the American bird is different from the European.
Listen to the sound of Hawk Owl
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|wingspan min.:||74||cm||wingspan max.:||81||cm|
|size min.:||36||cm||size max.:||39||cm|
|incubation min.:||25||days||incubation max.:||30||days|
|fledging min.:||25||days||fledging max.:||30||days|
3-12 eggs, depending on food supply, are laid at intervals generally of one day, from mid-April to mid-May. Incubation is by the female only; the male hunting and bringing food to her. He will generally perch within 200 yards (180 m) of the nest. The regular presence of a single owl during late April is often a good indication that a nest is nearby. Incubation begins with the first egg and lasts for 28-35 days. If food is scarce, only the oldest and largest nestlings will get food and the smaller young will perish. The young leave the nest and start to branch out at 20-22 days old, well before they can fly. Hawk Owls are very aggressive at their nests and will attack any intruders. This is especially evident just after the young have left the nest. After the young are large enough to hunt for themselves, they disperse extensively within the boreal forest zone in response to food availability.
Video Hawk Owl
Surnia ulula is a widespread resident in northern Europe, which accounts for less than
a quarter of its global range. Its European breeding population is small (as few as
9,200 pairs), but was broadly stable between 1970-1990. The extent of the fluctuation
in Russia during 1990-2000 was unknown, but the species remained broadly stable
overall. Although the size of the European population could render it susceptible to
the risks affecting small populations, it is marginal to a much larger non-European
Most recent European eruptions (in 1956-8, 1961-2, 1964-5, 1971-2) have been on reduced scale compared with some earlier ones (this century: notably 1914-15, 1928-9, 1930-1, 1931-2, 1942-3, 1950-1), possibly because of reduced population size since early 1950s, but further large eruptions occurred 1976-7 and 1983-4. Erupting birds only infrequently cross Baltic, apparently a fairly effective water barrier, though during larger invasions vagrants have reached Britain, Denmark, and continental countries south to France, Yugoslavia, and Rumania.