The influence of male dominance on social interactions in black ducks and mallards

Abstract

The influence of male dominance on male-female social interactions was examined in black ducks, Anas rubripes, and mallards, A. platyrhynchos, that were raised from hatch in four different groups (male and female mallards; male and female black ducks; male mallards and female black ducks; male black ducks and female mallards). The mate preference of females, independent of the influence of male dominance, was determined by exposing females to four caged, isolated males, one from each different group. All females preferred the type of male they had been raised with since hatch. Females were then exposed to the same four males, now free-swimming, to determine how male dominance influenced the initial preference. Under these conditions, each female associated primarily with the most dominant of the four males, regardless of her initial mate preference. Mallards were the most dominant males in all tests. These results demonstrate that male dominance influences social interactions and is one factor contributing to hybridization between these two species.