Linking nest predation with brood parasitism in captive zebra finches: a multi-pair study

Abstract

Zebra finches (Taeniopygia guttata) are social, colonial nesting birds with moderate levels of intraspecific brood parasitism reported in both wild and captive populations. In a previous study, individually housed, captive zebra finch pairs responded to nest removal during the egg-laying period by parasitising simulated active conspecific nests. In the study reported here, we investigated the role of nest loss as a proximate trigger for parasitism in a more naturalistic setting: small groups consisting of three pairs per aviary. In three of ten experimental trials, females responded to nest removal during the egg-laying period by laying eggs in active neighbouring nests. This rate of parasitism was lower than that reported previously for individually housed pairs, and aggressive interactions between hosts and putative parasites were also observed. The results provide further support for the Hamilton–Orians hypothesis for the evolutionary origin of brood parasitism and highlight the influence of social context on the expression of brood parasitic behaviour. Together with qualitative descriptions of several previously unreported behaviours associated with nesting and brood parasitism in captive zebra finches, these experiments provide a functional context and methodology for future studies on zebra finches as a potential new model for the ecology and evolution of brood parasitism.