Brown-headed Cowbird (Molothrus ater) Science Article 1
Parental care is advantageous because it typically increases the survival ofgenetically related young. In contrast, parental care given to unrelated young incurs no benefit.A further cost of parental investment is that it reduces the future reproductive potential of thecaregiver. I examined whether eastern phoebes’ Sayornis phoebe future reproductive effort wasrelated to interspecific brood parasitism by brown-headed cowbirds Molothrus ater in priorbroods. In 2000 absolute and relative measures of change in clutch sizes from first to secondbreeding attempts were similar in parasitized and non-parasitized broods, while the latency torenest was several days shorter for parasitized broods.
Mark E. HAUBER, Folia Zool. 55(4): 367-374 (2006)