fisher vs mustelid

fisher

noun
  • A North American marten, Martes pennanti, that has thick brown fur. 

  • The fur of Martes pennanti. 

  • A person who catches fish, especially for a living or for sport; a person engaging in the pastime of fishing. 

mustelid

noun
  • Any carnivorous mammal of the diverse weasel family Mustelidae, which also includes badgers, otters, martens, mink and wolverines. 

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