brown falcon vs peregrine falcon

brown falcon

noun
  • Falco berigora, a member of the falcon genus found in the drier regions of Australia. 

peregrine falcon

noun
  • A medium-sized, very swift falcon, Falco peregrinus, that hunts small birds. 

How often have the words brown falcon and peregrine falcon occurred in a corpus of books? (source: Google Ngram Viewer )