Female mallard mating preferences for multiple male ornaments
- Cite this article as:
- Omland, K. Behav Ecol Sociobiol (1996) 39: 361. doi:10.1007/s002650050301
A study I conducted suggested that female mallards chose males based on natural variation in individual ornaments, especially the bill. Ornament manipulations were used to test experimentally whether females were choosing males based on ornament appearance. Four experiments were conducted: anterior shaving (removed the outer colored part of the head, neck and breast feathers), wing patch clipping, bill blackening and bill yellowing. Anterior shaving caused 15 of 16 males to have lower pairing success. Wing patch clipping did not affect pairing success. Bill blackening caused a significant decrease in rank pairing success, and bill yellowing caused a weaker, but not significant, decrease in success. Furthermore, the latter three manipulations had no significant effect on male dominance rank. Taken together with the findings of the natural variation study, this work shows that female preferences directly select for male ornamentation.