bullfinch vs redstart

bullfinch

noun
  • Any of various other Old World finches in the genus Pyrrhula. 

  • The Eurasian bullfinch (Pyrrhula pyrrhula). 

redstart

noun
  • Any of various insectivorous ground-feeding birds, mainly of the genus Phoenicurus. Many of the species have a red tail. 

  • A not closely related species of warbler native to the Americas, Setophaga ruticilla 

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