Heritability of Tail Coloration in Male American Kestrels
Tail variation and tail pattern in male American Kestrels Falco sparverius are heritable to male offspring. In animals, plumage coloration may act as signal to communicate social status, age, or individual quality. American kestrels show sexual dimorphism as well as a high variation in individual coloration for tail plumage patterns of male kestrels. We investigated the heritability of tail patterns using historical data and tail pictures of American Kestrel males and their offspring from years 2008-2012. Using a pattern and variation chart, we categorized the plumage type of adult males and their male offspring and measured the width of the subterminal band on kestrel tails. Although some adults and offspring had similar subterminal measurements, there was not a strong correlation. However, tail pattern and variation rating showed a stronger correlation between adult and offspring. Understanding heritability in plumage characteristics that may act as signals will give insight to evolutionary ecology and population patterns of American kestrels.