bird's nest vs kennel

bird's nest

noun
  • Any tangle of fibers resembling a typical nest of a bird. 

  • A structure built by a bird as a place to incubate eggs and rear young. 

  • Any of several plants having some resemblance to the typical nest of a bird, eg, wild carrot (Dauca carota) 

kennel

noun
  • The hole of a fox or other animal. 

  • The dogs kept at such a facility; a pack of hounds. 

  • A house or shelter for a dog. 

  • A facility at which dogs are reared or boarded. 

verb
  • To house or board a dog (or less commonly another animal). 

  • To lie or lodge; to dwell, as a dog or a fox. 

  • To drive (a fox) to covert in its hole. 

How often have the words bird's nest and kennel occurred in a corpus of books? (source: Google Ngram Viewer )