Dietary conservatism in passerines : the influence of novel odour and novel colour

Abstract

This research was concerned with the way that passerine bird species use odour cues in isolation and in combination with colour cues to make decisions about new foods. Galliformes are known to demonstrate a disproportionately large latency to eat food with novel odour and novel colour cues. Passerine species, although possessing a smaller olfactory lobe than galliformes, are known to be able to detect odours at similar concentrations to galliformes. The behaviour of passerines towards these cues has how ever been poorly studied. In order to investigate the effects of environment and social structure on these behaviours, the experimental design was separated into three areas: solitary wild birds (birds which maintain winter territories), social wild birds (birds which form large feeding flocks in winter) and laboratory-held birds. The laboratory studies were envisaged to allow investigation of observed wild-type behaviour under controlled conditions.