Social and nutritional influences on the feeding of ring dove squab.

The effects of food deprivation on ring dove squabs' begging and pecking was examined during the period of transition from dependent to independent feeding. Food-deprived squabs begged more, pecked more, and were fed more by their parents than nondeprived squabs. When deprived, young squab primarily beg for food and older squab primarily peck. This difference may arise from the relative efficiencies of the two feeding responses at different ages. Additionally, parental state exerted control over the amount the squab pecked and begged. Parental food deprivation affected squab pecking, probably because hungry parents pecked more themselves and fed squabs less. Squab begging was not affected by parental food deprivation. However, parental separation from squab affected squab begging, as parents previously without squab were more likely to feed begging squab than were parents who were not separated from squab. Parental separation from squab did not affect squab pecking. The changes in the endogenous and exogenous controls of squab feeding allow for a great deal of plasticity in the transition from dependent to independent feeding.

Age differences in the controls of ring doves' pecking.

Three experiments investigated the endogenous and exogenous controls of ring dove pecking. Experiment 1 confirmed that deprivation modulates adult pecking although nondeprived subjects peak at high levels. Experiment 2 determined that the level of pecking in nondeprived birds is modulated by exogenous cues such as the salience of the seed. Experiment 3 analyzed some of the controls of pecking in squabs. Both nondeprived and deprived squabs pecked little on days 12 and 16 of life, but by day 18, deprived squabs pecked significantly more than nondeprived squabs. Squabs inexperienced with deprivation peck less when hungry than squab that have had previous experience with deprivation. The controls of feeding change between day 24 of life and adulthood as exogenous cues did not stimulate nondeprived squab pecking until day 24 of life.