Male polyterritoriality and imperfect female choice in the pied flycatcher, Ficedula hypoleuca

Polyterritoriality, the occupation of two spatially separateterritories by male birds, has been suggested to enable malesto conceal their pairing status. The idea that males deceivefemales has recently been questioned with arguments that femaleswould easily be able to detect polyterritorial males and thatthey mate in the second territories because better breedingoptions are not available close by. We arranged for pied flycatcher(ficedula hypoleuca) females a choice between neighboring unmatedand already-mated males. Females were unable to discriminateagainst already-mated males, even though their breeding successthereby would have been increased. These results allow rejectionof any polygyny models that assume females use male pairingstatus as a criterion for mate choice. Females would reducethe probability of mating polygynously by choosing dull, yearlingmales with high song rate, even though in most cases it is difficultto differentiate already-mated and unmated males. In fact, femalesdid not prefer colorful males, opposing a general pattern foundin other bird species. However, females did not specificallyprefer dull males nor did they respond to slight differencesin song rates. The seemingly nonadaptive, imperfect female behaviorsuggests that the evolution of female selectivity is constrained,allowing deception by males to be successful in the evolutionary‘arms race’ between the sexes. Behav Ecol 1990,-1:171–177]