Abstract Title
Plumage Variation in Nestling Barn Owls: Patterns of Pheomelanin and Eumelanin Pigmentation Differ Between Males and Females
Additional Funding Sources
This research, conducted at the Raptor Research Experiences for Undergraduates site, was supported by the National Science Foundation under Grant No. DBI-1852133 and by Boise State University.
Abstract
Higher vertebrates synthesize two forms of melanin pigmention: eumelanin and pheomelanin. Eumelanin is responsible for dark colors and is found in virtually all animal groups, whereas pheomelanin is the pigment underlying chestnut coloration and only synthesized in birds and mammals. The plumage of Barn Owls (Tyto alba) contains spots composed of eumelanin, and the absence or presence of pheomelanin influences whether owl body feathers are white or reddish brown, respectively. We were interested in the extent to which both melanin forms varied in nestling Barn Owls, how melanin pigmentation differed between sex classes, and whether males and females could be differentiated from plumage differeces. We measured plumage in nestling Barn Owls in southern Idaho during the 2019 breeding season. We quantified spot density in six body regions and, for the breast and abdomen, calculated average spot diameter from photographs of each owl. Pheomelanin was indexed in the same six body regions using comparisons to Munsell color chips. Finally, we used DNA obtained from blood to ascertain sex of each individual. Our poster describes characteristics of pheomelanin and eumelanin pigmentation and results of statistical analyses designed to assess the accuracy of sexing nestling Barn Owls from plumage characteristics.
Plumage Variation in Nestling Barn Owls: Patterns of Pheomelanin and Eumelanin Pigmentation Differ Between Males and Females
Higher vertebrates synthesize two forms of melanin pigmention: eumelanin and pheomelanin. Eumelanin is responsible for dark colors and is found in virtually all animal groups, whereas pheomelanin is the pigment underlying chestnut coloration and only synthesized in birds and mammals. The plumage of Barn Owls (Tyto alba) contains spots composed of eumelanin, and the absence or presence of pheomelanin influences whether owl body feathers are white or reddish brown, respectively. We were interested in the extent to which both melanin forms varied in nestling Barn Owls, how melanin pigmentation differed between sex classes, and whether males and females could be differentiated from plumage differeces. We measured plumage in nestling Barn Owls in southern Idaho during the 2019 breeding season. We quantified spot density in six body regions and, for the breast and abdomen, calculated average spot diameter from photographs of each owl. Pheomelanin was indexed in the same six body regions using comparisons to Munsell color chips. Finally, we used DNA obtained from blood to ascertain sex of each individual. Our poster describes characteristics of pheomelanin and eumelanin pigmentation and results of statistical analyses designed to assess the accuracy of sexing nestling Barn Owls from plumage characteristics.
Comments
T77