razorback vs shitehawk

razorback

noun
  • The rorqual or finback whale. 

  • A feral pig. 

shitehawk

noun
  • The European herring gull. 

  • An objectionable person; a twat or wanker. 

  • A large scavenging or predatory bird; especially (originally in military use in South Asia) the black kite. 

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