Dietary biology of the Eurasian eagle-owl own weight, and will kill the young of much larger species such as European otter ("Lutra lutra") and Eurasian badger ("Meles meles"). However, the single most widely reported carnivore is the red fox ("Vulpes vulpes"), as they’ve been recorded in the diet from Denmark and Spain to the Russian Far East. Many fox specimens taken by eagle-owls are young individuals or subadults. Some studies posited that the average fox taken as weighing about , about equal to the eagle-owl’s own weight, but another noted fox specimens killed that were estimated to weigh , much larger than the eagle-owls. At least
Meles (genus) has been much discussion as to whether it is a single species or three distinct species. There are geographical differences between individuals from different parts of the range in skull structure, morphology of the first premolar teeth, and facial markings. Some authorities advocated placing European and Asian badgers in separate species, "Meles meles" and "Meles leptorhynchus" (Milne-Edwards, 1867), the boundary between the two being the Volga River. Others considered there to be three subspecies, "M. m. meles", found west of the Volga, "M. m. arenarius-leptorhynchus", found between the Volga and Transbaikalia, and "M. m. amurensis-anakuma" from the Amur region and