A SEXUAL CONFLICT IN COLLARED FLYCATCHERS, FICEDULA-ALBICOLLIS - EARLY MALE MOLT REDUCES FEMALE FITNESS

A sexual conflict over levels of parental care occurs in most animals with biparental care, and studies of sexual differences in levels of p arental care have usually focused on its intra-annual fitness conseque nces. We investigated inter-annual fitness consequences of a sexual di fference in timing of feather replacement (moult) in collared flycatch ers (Ficedula albicollis). In this study, males overlapped reproductio n and moult more often than females, they also initiated their moult a t an earlier stage of breeding than females. Females mated to males wi th a moult-breeding overlap had significantly lowered survival chances than females mated with males initiating moult after breeding. Furthe rmore, females mated with moulting males risked a lowered future fecun dity in terms of a delayed start to breeding in the following season. However, early moulting males achieved a similar reproductive success as males initiating moult after breeding. Likewise, male survival prob ability to the following breeding season did not differ between early and late moulting individuals, nor was there any evidence that males g ained or lost in future mating advantages by moulting early. These res ults show not only that a sexual conflict over timing of moult may ope rate, but also that it can impose severe fitness consequences, in term s of future reduced fecundity and survival probability, upon the 'losi ng' sex.