laughing gull vs northern lapwing

laughing gull

noun
  • A common European gull (Xema ridibundus). 

  • An American gull (Leucophaeus atricilla); in summer the head is nearly black, the back slate color, and the five outer primaries black. 

northern lapwing

noun
  • A crested plover, Vanellus vanellus. 

How often have the words laughing gull and northern lapwing occurred in a corpus of books? (source: Google Ngram Viewer )