But reproductive success does not only depend on the best genes and the best nest, it also depends on parenting skills. Researchers from Konrad Lorenz Institute of Ethology, supported by the "Sparkling-Science" Program, investigated the effect of female ornamentation on the chick-rearing behavior of their mates. Both males and female blue tits have feathers on the top of their heads which reflect UV light. After their chicks had hatched, female blue tits were captured and their crowns smeared with either duck preen gland oil containing UV-blocking chemicals or the oil alone.
Although the UV-blocking chemicals did not alter the behavior of the females, their mates made fewer hunting trips to feed their brood. However the males made the same effort to protect their nest and defend their chicks as males with oil-only treated females.
Dr Matteo Griggio, co-author of this study, commented, "This is the first study to show that male blue tit behavior depends on female ornamentation. Even though our experiment was minimally invasive to avoid partners not being able to recognize each other, the behavior of male blue tits in this study matched the DAH. DAH also predicts that less attractive females should increase their parental investment but we found no compensatory female behavior."