osprey vs western osprey

osprey

noun
  • A bird of prey (Pandion haliaetus) that feeds on fish and has white underparts and long, narrow wings each ending in four finger-like extensions. 

  • aigrette (ornamental feather) 

western osprey

noun
  • A fish-eating bird of prey of the species Pandion haliaetus. 

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