warbler vs yodeler

warbler

noun
  • One who warbles. 

  • A hissy fit. 

  • Any of various small passerine songbirds, especially of the family Sylviidae (Old World warblers) and Parulidae (New World warblers). 

yodeler

noun
  • One who sings so that their voice fluctuates rapidly between their normal chest voice and a falsetto, one who yodels. 

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