Reproductive effort and success of wild female mallards : does male quality matter? / Jennifter L. Sheppard, Robert G. Clark, James H. Devries, and Michael G. Brasher.

Includes bibliographical references (pages 89-90).

tIn accordance with the differential allocation hypothesis, females are expected to increase their repro-ductive investment when mated to high-quality males. In waterfowl, reproductive, investment increasedwhen captive female mallards (Anas platyrhynchos) were mated to more attractive males, but informationfor wild ducks is lacking. Studies of waterfowl mating systems have focused primarily on the importanceof plumage coloration of males and female mate choice, whereas investigations of reproductive ecologyexamine female attributes and virtually ignore the role of males in investment decisions. Here, we usedunique data for 253 pairs of wild mallards to test whether females mated to high-quality males wouldincrease reproductive effort and reproduce more successfully. We derived measurements of female andmale body size and condition, and indices of male plumage quality, and related these traits to patternsof reproductive effort and performance of females. Consistent with predictions, yearling females nestedearlier and had higher nest survival when mated to males with better plumage scores. Furthermore,when paired with larger bodied males, yearling females renested more often, and nest and brood sur-vival increased among older females. Although the strength of male effects varied with breeding stageand female age or experience, this is one of a few studies to demonstrate an additive effect of male qualityon investment and success of females, in free-ranging birds.