フクロウ
The Ural owl is a rather large species. Full-grown specimens range in total length from , which may render them as roughly the eight longest owl species in the world (though many owls are heavier on average). Wingspan can vary in the species from . Like most birds of prey, the Ural owl displays reverse sexual dimorphism in size, with the female averaging slightly larger than the male. Reportedly talon size and body mass is the best way to distinguish the two sexes of Ural owl other than behavioral dichotomy based on observations in Finland. Weight is variable through the European part of the range. Males have been known to weigh from and females have been known to weigh from . Voous estimated the typical weight of males and females at and , respectively. It is one of the larger species in the "Strix" genus, being about 25% smaller overall than the great grey owl, the latter certainly being the largest of extant "Strix" species in every method of measurement. Body masses reported for some of the more southerly Asian species such as brown wood owl ("Strix leptogrammica") and spotted wood owl ("Strix selopato") (as well as the similarly sized but unweighed mottled wood owl ("Strix ocellata")) show that they broadly overlap in body mass with the Ural owl or are even somewhat heavier typically despite being somewhat smaller in length. Despite having no published weights for adults, Père David's owl ("Strix davidi") seems to also be of a similar size to the Ural owl as well. Among standard measurements, in both sexes, wing chord can measure from across the range and tail length can from . Among extant owls, only the great grey owl is certain to have a longer tail. Though less frequently measured, the tarsus may range from and, in northern Europe, the total bill length measured from . The foot span can regularly reach around in full-grown owls.