Bethany N. Belock and Doris J. Watt Biology Department Saint Mary’s College, Notre Dame, IN

1. An Examination of the Role of Weight, Plumage Color, Cere Color and Total Area of UV Reflectant Crown Plumage on Mate Selection in Budgerigars (Melopsitticus undulates) Bethany N. Belock and Doris J. Watt Biology Department Saint Mary’s College, Notre Dame, IN ABSTRACTThe purpose of this study was to determine the influence of four physical traits (weight, plumage color, cere color and area of UV reflectant plumage) on the mate selection process in Budgerigars (Melopsitticus undulates). Seven male and six female Budgerigars of various plumage colors and UV patch sizes were studied. The birds were housed in an aviary and provided with nest boxes when they reached sexual maturity. Periodic observations were made through a one way window over the course of 4 months and the birds’ social interactions were recorded. The results showed that weight was not a reliable indicator for determining a bird’s ability to attract a mate. Plumage color, on the other hand, may have been a factor contributing to mate selection, as most birds paired with a mate of similar coloration. The female’s cere color may be associated with mate selection as well, but the color of the male’s cere seems irrelevant. Two of the first pairs to form and produce eggs involved males with large UV patch sizes. There were, however, two other pairs of blue and white birds that mated quickly and produced eggs. Additionally, the male with the largest UV patch size was the only male not to bond with a female. This suggests that UV patch size alone is not a reliable indicator of the bird’s ability to attract a mate and that it is likely that there are other signals being utilized. Additional studies will need to be conducted using larger sample sizes to determine the extent to which each of the four factors examined have on the mate selection process.