Individuals may show striking variation in how they respond to new foods: some individuals will consistently consume new foods (adventurous consumers), while others refuse to incorporate them into their diet despite repeated feeding opportunities (conservative consumers). The expression of dietary conservatism in wild populations may have important consequences for foraging success in areas where humans discard food, and may be crucial in predicting responses to novel invasive prey or human-made poisons. However, patterns of dietary conservatism in human commensal species remain largely unexplored. It is not known whether all species show individual variation in dietary conservatism, and whether, in group living animals, its expression is influenced by the behaviour of other conspecifics in the group. The corvid family is ideal for studying dietary conservatism because they are known for avoiding novelty in other contexts, yet they are successful in habitats alongside people and are adept social learners. We investigated whether a wild population of individually-marked jackdaws (Corvus monedula) had distinct classes of adventurous and conservative individuals, and whether observing conspecifics consuming novel foods influenced subsequent food choices. We presented groups of birds with combinations of novel and familiar food types, and measured the number of presentations individuals needed before they would approach and consume novel foods reliably. We found that individuals varied in their propensity to approach and consume novel foods, and that arbitrary food preferences arose in different groups based on experience and the presence of adventurous conspecifics. These results provide important insights into how groups of wild corvids adopt novel foods into their diet, and how this may allow them to exploit human-altered environments.