A comparison of pursuit flights by six North American ducks of the genus Anas

Abstract

The pursuit flights of six species of surface feeding ducks were compared. These aerial chases can be classified as Three-bird Flights or Attempted Rape Flights. Pursuit flights result in dispersion of the six species considered. Although there are important similarities in form and function, the characteristics of pursuit flights, the participants involved, raping tendencies and territorial behaviour differ considerably from one species to another. Based upon these criteria an alignment of the six species appears possible; from the strongly territorial Blue-winged Teal Anas discors and Shoveler A. clypeata through Gadwall A. strepera to Black Duck A. rubripes and Mallard A. platyrhynchos, with Pintail A. acuta exhibiting weak site attachment and a raping strategy at the opposite extreme.