[8] The eyes are dark brown, being relatively small and closely set to each other, which is opined to give them a less “fierce” countenance than that of a great grey owl (Strix nebulosa).
The tawny species, which occurs variously in grey, brown and red morphs, has underparts with dark shaft-streaks and crossbars, as opposed to the heavy but straight streaking of the Ural owl.
[5][19] Due to its partially diurnal behaviour during warmer months, some authors consider it confusable with the very different looking (but similarly largish and long-tailed) Eurasian goshawk (Accipiter gentilis).
[13] Conservatively, about 18 species are currently represented in this genus, typically being medium to large sized owls, characteristically round-headed and lacking ear tufts, which acclimate to living in forested parts of various climatic zones.
Authors have hypothesized that the origin of the species divide followed Pleistocene continental glaciations segregated a southwest or southern group in temperate forest (i.e. the tawny) from an eastern one inhabiting cold, boreal ranges (i.e. the Ural).
[4][41][42][43][44][45] A hybrid was recorded in captivity between a male Ural and a female tawny owl, which managed to produce two offspring that were intermediate in size and had a more complex song that was also shared some characteristics with both species' vocalizations.
[1][5][18][59][60][61][62] The distribution in Germany is particularly nebulous (and perhaps aided by reintroductions branching from the well-known Bavarian population), with evidence of Ural owls apparently residing (and possibly nesting) considerably away from currently known haunts in Egge far to the west and mysteriously turning up rather to the north in Harz and Lüneburg Heath.
In western and European Russia, it is found as far south roughly as the Bryansk, Moscow and northern Samara north continuously to Kaliningrad, the southern part of the Kola Peninsula and Arkhangelsk.
Reportedly the countries of Slovakia, Slovenia then Romania have the most extensive ideal habitat in the Carpathians and resultingly have the highest local densities of Ural owls, perhaps in all of Europe.
[4][8] On the contrary, in some peri-urbanized areas of Russia, such as the metropolitan parks and gardens so long as habitat is favorable and encouraging of prey populations, the Ural owl has been known to successfully occur.
However, taken as a whole and since it mainly lives the taiga zone where very long summer days are the norm against extensive dark during the winter, Ural owls are not infrequently fully active during daylight hours during the warmer months, while brooding young.
[4][5][8] In addition, any variety of small mammal, to the size of hares (albeit usually young ones), may too be fairly often taken, as well as variable numbers of birds, amphibians and invertebrates, with reptiles and perhaps fish being very rare prey.
When the same biologists observed the foraging patterns on field mice and also voles, they similarly learned and showed a preference for the patches that held larger species over smaller ones.
[89][105] Camera traps recording captured 187 prey items for Ural owls in 5 nests in Värmland County, Sweden found that voles were secondary in delivery rates to common shrew (Sorex araneus) and various birds with the small size of such prey requiring frequent deliveries although this was offset with fair numbers of young hares apparently available to these owls.
More locally in a smaller block within Slovenia, up to 58.8% by number and 94.4% by biomass in the Ural owl's diet is compromised by the edible dormouse, whose adult body mass can vary from 62 to 340 g (2.2 to 12.0 oz).
In the Yatsugatake Mountains, 1026 small mammals were identified at 17 Ural owl nest of which Apodemus species compromised 71%, followed by voles, at 24%, and Japanese shrew mole (Urotrichus talpoides), at 5%.
[122] One large mammalian prey widely associated with Ural owls are hares, though they seldom occur in substantial numbers in the diet, they appear to be opportunistically taken in most parts of the range.
[16][115] On infrequent occasions, Ural owls may be able to overtake bird prey of up to approximately their own size or somewhat larger, i.e. up to or slightly over 1,000 g (2.2 lb) in average body mass, such as adult mallard (Anas platyrhynchos), common goldeneye (Bucephala clangula), black grouse (Tetrao tetrix), common pheasant (Phasianus colchicus), chicken (Gallus gallus domesticus), black-crowned night-heron (Nycticorax nycticorax) and some accipitrids as well as, so far as is known, only young specimens of the larger still western capercaillie (Tetrao urogallus).
In the Kagawa Prefecture, an exceptional 24% of the diet consisted of insects and furthermore in Kyoto, Ural owls were observed to be routinely pursuing and eating Japanese rhinoceros beetles (Allomyrina dichotoma).
Most sympatric species also share a preference for small mammals, largely voles, especially when they occur in relatively northerly temperate places such as the haunts of the Ural owls.
[4][146][152][153] In Primorsky Krai, Asian badgers (Meles leucurus) and raccoon dogs (Nyctereutes procyonoides) are mentioned as potential or likely predators of Ural owls nests as well.
[4][7][30][85][117][138][146] Diurnal raptors are also sometimes vulnerable to predation by Ural owls, including grey-faced buzzards (Butastur indicus), Eurasian sparrowhawk (Accipiter nisus), common kestrel (Falco tinniculus) and even apparent adult northern goshawks.
[158] On the contrary, experimental ground nests put out by researchers with random poultry eggs in central Finland were shown to be incidentally protected by the fierce presence of Ural Owls.
The peak Croatian population was recorded in Plitvice Lakes National Park, predominately in mixed fir-beech montane forest, which held about 38 breeding pairs.
With as many as three breeding attempts, Density was estimated at 0.6-0.9 pairs per 10 km2 (3.9 sq mi), 3-10 times lower than other nearby ranges in eastern Europe like the Low Beskids and Bieszczady Mountains.
[164] In Russia's Altai Krai, Biya River area between 2010 and 2012, 15.2-48.9% of nest boxes that were erected were used with annual variation explainable by cycles of primary food sources.
[9] Use of 15 total nest boxes in Akademgorodok, Russia over three study years varied wildly based presumably on prey population cycles with anywhere from 0% to 50% used annually.
[4] 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.
[189] Despite being farther south than many aforementioned studies (i.e. from Fennoscandia), in Estonia a highly variable breeding success rate was observed to be concurrently happening during prey population cycles.
[204] Post-dispersal young from Vienna Woods in Austria were radio-tracked and showed a mean dispersal distance of 8,778 m (28,799 ft) from release site and were shown to experience about a 23% mortality rate.