Food avoidance by adult house finches, Carpodacus mexicanus, affects seed preferences of offspring

Abstract

In altricial birds, the food habits of young birds may be affected by extended parental contact. To examine this, five nesting pairs of captive adult house finches were exposed to hulled oats treated with an aversive agent, methiocarb. During the nestling and early fledgling stages, juvenile finches raised by adults that avoided oats received 30–40 times less exposure to hulled oats than did juveniles raised by adults that ate oats. After they were separated from the adults, the juveniles had no further access to oats or to canary seed, the alternative untreated food, until tested individually at 10–12, 20–22, and 35–38 weeks of age. There was no relationship between the juvenile birds’ exposure to oats in the early nestling stage and their subsequent oat preference scores. Birds raised by adults that avoided oats during the late nestling and fledgling stages, however, displayed lower oat preference scores than did birds raised by adults that ate oats. Thus, dietary aversion to oats established in adult birds was expressed in the seed preferences of their offspring.