bergylt vs orange roughy

bergylt

noun
  • The rose fish, an edible red fish found in the North Atlantic, Sebastes norvegicus. 

  • The Ballan wrasse, Labrus bergylta another North Atlantic fish 

orange roughy

noun
  • An edible deep-sea fish, Hoplostethus atlanticus, belonging to the slimehead family (Trachichthyidae). 

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