Resource polymorphism refers to individuals from the same population foraging in alternative habitats or on alternative food. Food specialization can be associated with adaptations such as colour polymorphism, with pale and dark colours conferring differential camouflage in different habitats. Pale and dark-reddish pheomelanic Barn Owls (Tyto alba) forage on different prey species in closed and open habitats, respectively. We show here that darker-reddish owls have heavier stomach content when found dead, and their 5th secondary wing feather is more deeply anchored inside the integument. These correlations suggest that their feathers bend less when flying, and that darker-reddish Barn Owls are able sustain more intense flying than their paler conspecifics.
Bibliographical noteFunding Information:
Acknowledgments We thank Kobi Meyrom, Amir Ezer, and Shay Halevi for assistance in collection carcasses and Naomi Paz for editorial assistance. The study was financed by the Swiss National Science and Addax-Oryx Foundations.
© 2014, Dt. Ornithologen-Gesellschaft e.V.
- Colour polymorphism
- Stomach content
ASJC Scopus subject areas
- Animal Science and Zoology