Female pied flycatchers Ficedula hypoleuca choose male characteristics in homogeneous habitats

Summary The paper reports the results of a 2-year study of pairing success of male pied flycatchers in a homogeneous habitat. A handicapping experiment was carried out in which certain wing and tail feathers were removed from randomly selected males. Handicapped males had reduced pairing success, they lost weight, and they sang less frequently than control males. Male pairing success was positively correlated with the darkness of the plumage, body-size, and previous breeding experience. Earlier studies on the same species have failed to detect any relationships between pairing success and male characteristics, possibly because of habitat heterogeneity and variation in nest site quality. The evolutionary basis for female choice of male characteristics is discussed. There are reports that males with attractive traits (e.g. black plumage) provide a high quality of parental care. However, the fact that male pairing success was related to male conspicuousness makes it difficult to discriminate between active and passive female choice.