Aversions of Starlings and Sparrows to Unfamiliar, Unexpected or Unusual Flavours and Colours in Food

Captive starlings Sturnus vulgaris and house sparrows Passer domesticus were studied to explore the effects of previous experience on birds' aversions to quinine sulphate in blue‐coloured food. Daily food consumption and feeding behaviour were monitored for four groups of birds: (1) Control—birds trained to associate blue with quinine; (2) Unfamiliar—never having previously encountered blue or quinine; (3) Unexpected—trained to regard blue as palatable; (4) Anomalous—familiar with quinine in red, but not in blue food. Comparisons of these groups are discussed in relation to the way in which aversions are established, their implications for understanding birds' food selection behaviour, and the use of chemicals as bird deterrents in crop protection.