Observational Learning of Food Aversions in Red-Winged Blackbirds (Agelaius phoeniceus)

Abstract

-Recent work has demonstrated that Red-winged Blackbirds (Agelaius phoeniceus) display food preferences as a result of observational leaming. Also, individual birds learn to avoid food the ingestion of which has been paired with sickness. Such preferences or aversions depend on visual cues associated with the food. A related but unanswered question is whether observational leaming is sufficient for birds to associate visual cues with sickness. In the present experiments, Red-wings observed a conspecific consume a food paired with a color cue (CS) and toxin-induced illness (UCS). The observers were subsequently given two-choice preference tests between a food (either the food consumed by the gavaged bird or another food) paired with the CS or with another color. The birds avoided consumption of any food paired with the CS (but not of the other color) during all tests. Such results are consistent with the notion that opportunistic foragers, such as Redwings, readily learn to avoid conspicuous foods paired with aversive consequences. Moreover, the results support the notion that Batesian model-mimic systems could be maintained, at least in part, by observational learning of models and subsequent generalization of that learning to mimics. Observational learning could provide an efficient strategy to protect against the ingestion of potentially dangerous food. Received 15 July 1981, accepted 12 De-