Eurasian eagle owl vs eagle owl

Eurasian eagle owl

noun
  • Bubo bubo, the largest owl, native to almost all of temperate Eurasia. 

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. 

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