figpecker vs pettychaps

figpecker

noun
  • A bird, the western Orphean warbler, Sylvia hortensis, prized by gourmets. 

pettychaps

noun
  • Any of several species of small European passerine songbirds, including the willow warbler (Phylloscopus trochilus), the chiffchaffs (Phylloscopus spp.), and the western Orphean warbler (Sylvia hortensis). 

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