New Zealand pigeon vs culver

New Zealand pigeon

noun
  • A large species of pigeon, Hemiphaga novaeseelandiae, native to New Zealand. 

culver

noun
  • A culverin, a kind of handgun or cannon. 

  • A dove or pigeon, now specifically of the species Columba palumbus. 

How often have the words New Zealand pigeon and culver occurred in a corpus of books? (source: Google Ngram Viewer )