dolphinfish vs dorado

dolphinfish

noun
  • A large food and game fish of the Coryphaenidae family which is commonly found in tropical and subtropical waters. 

dorado

noun
  • Coryphaena hippurus, the mahi-mahi or dolphin, a species of fish with a dorsal fin that runs the length of the body, also known for iridescent coloration. 

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