Due to her attacks, the predation rate on Ural owl is often exceptionally low. However, based on territory spacing, the boreal owls can appear to more strictly avoid the tawny owl, which is known to be highly aggressive in its territorial behaviour year-around while studies have indicated territorial exclusion by Ural owls is largely confined to the breeding season.  Prey consists mostly of various species of rodent, though shrews and, locally, moles can be a regular food source as well. Kontiainen, P., Pietiäinen, H., Karell, P., Pihlaja, T., & Brommer, J. E. (2010). Dravecký, M., Danko, Š., Obuch, J., Kicko, J., Maderič, B., Karaska, D., Vrana, J., Sreibr, O., Šotnár, K., Vrlik, P. & Bohačík, L. (2008). Kontorshikov, V. V., Greenchenko, O. S., Ivanov, A. V., Petrisheva, A. P., Sevrugin, A. V., & Chelintsev, N. G. (1996). , Shrews of nearly 20 species are taken more or less throughout the Ural owl’s range.  The great grey owl is larger than the Ural owl with a huge head and relatively even smaller yellow eyes while their facial disc has strong concentric lines.  In the small Swedish study from Värmland County, an exceptional 12.2% of delivered prey was common frogs (Rana temporaria). Hakkarainen, H., Korpimäki, E., Koivunen, V., & Kurki S. (1997). Matsyna, A. I., Matsyna, E. L., Matsyna, A. Komorová, P., Špakulová, M., Hurníková, Z., & Uhrín, M. (2015). The mean size of mountain hares taken in Finland have variously been estimated at 173 to 2,000 g (0.381 to 4.409 lb), with a common median being about 500 g (1.1 lb). The densities of territories range between 0.9 to 13.4 territories per 10 km 2, and the highest densities are reached in montane forests of the southern dinaric region. Size: 62 cm; Wingspan: 124 à 134 cm.  Breeding success is often strongly correlated with prey populations.  More similar than any in Europe, the closely related Père David's owl does not occur in the same range as (other?)  Egg sizes are usually between 46.5 and 52.3 mm (1.83 and 2.06 in) in height by 39 to 44 mm (1.5 to 1.7 in) in diameter, and the eggs weighing on average about 47 g (1.7 oz) when fresh.  The male’s song may carry up to 2 km (1.2 mi) to human perception but usually is considered not quite that far-carrying. the European green woodpecker (Picus viridus) from the more northern transcontinental grey-headed woodpecker (Picus canus). adult.  Historically, European birdwatchers often consider the species to be rather elusive and hard to observe.  In Finland, the repeatability of the nesting defense behaviour by females was ranked as 52.4%, starting with a bark and taking flight, then fly-bys towards the perceived threat and culminating in attacks and powerful strikes. Full-grown specimens range in total length from 50 to 62 cm (20 to 24 in), which may render them as roughly the eight longest owl species in the world (though many owls are heavier on average). Wink, M., El-Sayed, A. Forest : Boreal, Temperate ; Wetlands (inland) : Bogs, Marshes, Swamps, Fens, Peatlands ; Artificial/Terrestrial : Pastureland, Rural Gardens, Updated on 2020/11/29 01:37:41  However, in Scandinavia, Ural owls were reported to hunt more like goshawks rather than the more still-hunting tawny owls, with a perch-hunting method wherein they fly in brief spurts from perch to perch, with the flights meant to be inconspicuous until prey is detected.  Being smaller than the great grey owl and Eurasian eagle-owl, it is projected that the Ural owl can live off of less food overall than them. Despite its large size, the great grey owl is a dietary specialist on voles, relying almost exclusively on them.  Vagrancy has been reported in Europe and Russia, which may account for sightings of the species almost throughout Germany.  In Finland, food niche breadth for Ural owls overlapped about 73% with the tawny owl but the mean prey size was more than twice as much for the Ural owl, 38.4 g (1.35 oz) for tawny vs 78.1 g (2.75 oz) for Ural, and the tawny owl was recorded to take non-mammalian prey significantly more so than Ural owls.  Mean clutch size in Finland was 2.24 but could range from 2.08 to 3.98 on average in poor and good years for vole prey. By the 1990s, the number had grown to 1000-1500 pairs in the western Carpathians and to 220-1350 pairs in northern Belarus. The underparts are pale cream-ochre to grey-brown and are boldly (though sometimes more subtly) overlaid with dark brown streaking, without crossbars.