The Pacific koel is a
brood parasite. In Australia, their hosts are mainly large
honeyeaters (especially
noisy friarbirds and
red wattlebirds). Unlike in other parasitic cuckoos, the young do not attempt to kill the host chicks. This trait is shared with the
channel-billed cuckoo, which – as in the Pacific koel – are largely
frugivorous as adults. A study of vocalization noted that the duetting behaviour may indicate the possibility of short-term pair-bonding in its otherwise
polygynous mating system. In Australia, the presence of the species is regarded as a sign of the arrival of spring and the rainy season. It is also viewed as a nuisance due to the males' incessant calling throughout the day and night. The calls indicate the start of breeding season and males would call repeatedly to mark their territory or communicate their availability to other females. ==Gallery==