Examining the preferences of broods of mallard ducklings, Anas platyrhynchos platyrhynchos

In their natural habitat, ducklings are members of a brood. In imprinting experiments, ducklings are usually tested individually. However, testing ducklings individually does not allow researchers to test for the potential role of social dynamics in the formation of attachments. We describe a procedure for testing ducklings as a brood and report four experiments in which we tested this method. In the first experiment, we exposed experimental broods consisting of 10 mallard ducklings to a stimulus brood of three ducklings or three empty quadrants. The experimental broods preferred the stimulus brood more than the empty quadrants. In the second experiment, we exposed experimental broods to stimulus broods of three and nine ducklings and two empty quadrants. The stimulus brood of nine was preferred more than the other quadrants. The third and fourth experiments examined preferences for even larger stimulus broods and the effect of using a larger testing platform on the preferences shown. These experiments suggest an effective method for testing the preferences and developmental dynamics of broods of ducklings.