The effect of Jacobin CuckooClamator jacobinusparasitism on the body mass and survival of young in a new host species

Abstract

The southern African subspecies of Jacobin CuckooClamator jacobinus serratusis a brood parasite of a range of host species. While Jacobin Cuckoos do not evict host young, previous research has found that host young rarely survive the nestling period. Here we provide the first records of Jacobin Cuckoo parasitism of a new host species, the Southern Pied BabblerTurdoides bicolor. We investigate rates of brood parasitism and the survival of host young. The Southern Pied Babbler is one of the largest recorded hosts for Jacobin Cuckoos and, unusually, we find that host young tend to survive the nestling period and maintain similar body mass to host young in unparasitized broods. However, host young were less likely to survive to independence than young raised in unparasitized nests, suggesting a post‐fledging reproductive cost to hosts.