Reproductive biology of female Saffron Finches does not differ by the plumage of the mate

ANDRÉS G. PALMERIO; VIVIANA MASSONI

THE CONDOR

The Cooper Ornithological Society

Año: 2009 vol. 111 p. 715 - 721

0010-5422

Abstract: Young, immature plumaged males of species showing delayed plumage maturation are often unable to obtain mates or pair later in the season to lower quality females. Their nests have smaller clutch size and lower quality of eggs, leading to lower number of nestlings of reduced quality and fledging success. The Saffron Finch (Sicalis flaveola pelzeni) is an understudied and declining secondary cavity species with delayed plumage maturation, their yearling males looking alike females. The aims of this study were to compare the morphology of immature and mature plumaged males of the Saffron Finch and their respective females, and the breeding success of females mated to each type of male in a nestbox system. We expected females mated to immature plumaged males would follow the pattern described for other species, showing lower reproductive investment and success. Immature and mature plumaged males were similar in morphology, but females paired to mature plumaged males were bigger in bill height and weight. However, we found no differences between females paired to each type of male at any biologically meaningful variable. Reduced male-male competition for secondary cavities and enough females willing to pair to immature plumaged males might be partially responsible for these results.