eared seal vs harbor seal

eared seal

noun
  • A seal belonging in the Otariidae family; a fur seal or a sea lion, differing from the true seals in having small, visible ears and the ability to walk on land. 

harbor seal

noun
  • A species of true seals, Phoca vitulina. 

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