Eurasian eagle-owl
The Eurasian eagle-owl ("Bubo bubo") is a species of eagle-owl that resides in much of Eurasia. It is also called the European eagle-owl and in Europe, it is occasionally abbreviated to just eagle-owl. It is one of the largest species of owl, and females can grow to a total length of 75 cm (30 in), with a wingspan of 188 cm (6 ft 2 in), males being slightly smaller. This bird has distinctive ear tufts, with upper parts that are mottled with darker blackish colouring and tawny. The wings and tail are barred. The underparts are a variably hued buff, streaked with darker colour. The facial disc is poorly developed and the orange eyes are distinctive.
Verreaux's eagle-owl
Despite the alternate common name of giant eagle-owl, the Verreaux's eagle-owl is not the largest owl or eagle-owl in the world. It is, however, a very large and powerful owl species. This species is both the largest owl found in Africa and the world's largest owl to occur in the tropics. Among all the world's owls, it is fourth heaviest living owl, after Blakiston's fish owl ("Bubo blakistoni"), the Eurasian eagle-owl ("Bubo bubo") and the tawny fish owl ("Bubo flavipes"), and is also the fourth longest living owl (measured from the bill to the tip of the tail), after the great gray ("Strix nebulosa"), Blakiston's fish and Eurasian eagle-owls. Based on body mass and wing chord length, Verreaux's eagle-owl is about the same size as "medium-sized" races of Eurasian eagle-owl, such as those from Central Asian steppe ("B. b. turcomanus") and the Himalayas ("B. b. hemachalana"), slightly smaller than most northern Eurasian races, considerably smaller than Siberian and Russian eagle-owls, and somewhat larger than the smallest Eurasian eagle-owl subspecies, such as those from the Iberian Peninsula ("B. b. hispanus") and the Middle East ("B. b. omissus" or "nikolskii").