Spatial diversity in the diet of the Eurasian Eagle Owl Bubo bubo in Iran

During five stays in Iran, the author collected remnants of the diet from seven species of owls. The most numerous were samples from the Eurasian Eagle Owl Bubo bubo, which were found in 38 sites, usually on rocky cliffs where the owls breed or where they roost during the day. A total of 7,862 items of prey were analysed. Mammals predominated (Mammalia, 56 species, 77.0%), and the species representation of birds was diverse (Aves, more than 100 species, 15.3%); lower vertebrates were hunted less often (Amphibia, Reptilia, Pisces, 5.0%), while invertebrates (Evertebrata, 2.7%) were an occasional food supplement. The most commonly represented rodents (Rodentia) in the Elborz and Talysh Mountains were: Snow Vole Chionomys nivalis, Steppe Field Mouse Apodemus witherbyi and Common Vole Microtus obscurus; in the northern part of the Zagros Mountains: Brandt’s Hamster Mesocricetus brandti, Williams’ Jerboa Allactaga williamsi and Setzer’s Mouse-tailed Dormouse Myomimus setzeri; in the central wetter part of the Zagros: Persian Jird Meriones persicus, Tristam’s Jird Meriones tristrami, Transcaucasian Mole Vole Ellobius lutescens and Grey Hamster Cricetulus migratorius; in the drier part of the Zagros: Libyan Jird Meriones libycus, Sundevall’s Jird Meriones crassus and Indian Gerbil Tatera indica; in the southern part of the Zagros in Fars Province: Iranian Vole Microtus irani, the rats Rattus rattus and R. norvegicus and mice Mus sp.; in the southeastern part of Iran: Short-tailed Bandicoot Rat Nesokia indica; and in the Koppeh Dagh Mountains: Southern Mole Vole Ellobius fuscocapillus, Afghan Vole Microtus afghanus, Midday Jird Meriones meridianus and Small Five-toed Jerboa Allactaga elater. Analysis of diet samples from the Eurasian Eagle Owl from the northern Zagros Mountains and eastern Turkey showed that Setzer’s Mouse-tailed Dormouse Myomimus setzeri occured only in samples from locations above 1800 m a.s.l., where Brandt’s Hamster Mesocricetus brandti was the predominant prey.