eagle owl vs horned owl

eagle owl

noun
  • Any of various Old World large owls of the genus Bubo, especially the Eurasian eagle owl, Bubo bubo, that have prominent ear tufts. 

horned owl

noun
  • An owl of the genus Bubo native to the Americas, among the largest types of owl, having two horn-like tufts of feathers on its head. 

How often have the words eagle owl and horned owl occurred in a corpus of books? (source: Google Ngram Viewer )