The owl family is well represented in the vast boreal forests of Eurasia and North America, but of all the northern owls there is one species that I seek above all others.The enigmatic hawk owl is a great wanderer and can be extremely hard to find, says Jari Peltomäki
Where do hawk owls live?
The hawk owl (Surnia ulula) makes its home in the vast boreal forests of the Northern Hemisphere and is found across Canada, Alaska, Scandinavia, and parts of Siberia. Its favoured habitat is dense coniferous woodlands, often near open areas like bogs and clearings where it can hunt more effectively.
How big are hawk owls?
Hawk owls weigh between 270-340g and are between 36-39cm long from head to tail. Their wingspan is 74-81cm.
What do hawk owls look like?
The hawk owl is a large, slender owl with a very long tail. It has a stern (almost grim) expression - created by slanted, snow-white 'eyebrows' and striking, black-streaked cheeks - that seems to suit its customary waywardness.
The hawk owl is a master of disguise, too. As it takes off from its lookout on top of a tall spruce, telegraph pole or aerial, it often appears to morph into another stealthy hunter - a female sparrowhawk. These two birds share a remarkably similar broad-winged silhouette and flight style (pulses of deep, powerful wing beats interspersed with graceful glides). But as soon as the kill is made and the owl returns to its perch, its identity becomes clear again.
What do hawk owls eat?
In Finland, the hawk owl is called hiiripöllö, or 'mouse owl', since over 95 per cent of its summer diet consists of small rodents. However, its chief targets are not mice but voles, especially field and tundra voles. Numbers of these mammals fluctuate dramatically, typically on a three- to fou year cycle, with boom followed by bust. In good vole years there may be up to 6,000 breeding pairs of hawk owls in Finland; when voles are scarce, just a handful of pairs nest Lack of food triggers an exodus of hawk owls to western o central Europe, where they delight crowds of birders.
In North America, snowshoe hares are a key part of their diet
How do hawk owls hunt?
Hawk owls hunt by both day and night over open ground such as clearings, fields, burned areas and heaths. If food is scarce, adults must hunt all day to satisty their hungry brood.
A hawk owl will often hover, especially if it can hear a vole moving under a carpet of snow. Having pinpointed the prey's position, the owl dives through the snow to snatch it.
How often do hawk owls breed?
Breeding starts in March. Female lays 4-13 eggs and incubates for 25-30 days.
Young spend six to eight weeks in parents' territory. Hawk-owl chicks leave the nest at about three weeks old, when still covered in down and unable to fly. To me, they look like little trolls as they totter over the ground and scramble up trees.
Where do hawk owls nest?
Old woodpecker holes are popular hawk-owl nest sites (in Europe, those of the black woodpecker are frequently used). The owls also nest in the tops of dead trees, especially spruce, aspen or birch, and will even use nestboxes.