Common chiffchaff point, appears to be used to advertise an established territory and contact the female, rather than as a paternity guard strategy. Beyond the core territory, there is a larger feeding range which is variable in size, but typically ten or more times the area of the breeding territory. It is believed that the female has a larger feeding range than the male. After breeding has finished, this species abandons its territory, and may join small flocks including other warblers prior to migration. The male common chiffchaff returns to its breeding territory two or three weeks before the female and immediately
Common chiffchaff the adults are hunted by birds of prey, particularly the sparrowhawk. Small birds are also at the mercy of the weather, particularly when migrating, but also on the breeding and wintering grounds. The common chiffchaff is occasionally a host of brood parasitic cuckoos, including the common and Horsfield's cuckoos, but it recognises and rejects non-mimetic eggs and is therefore only rarely successfully brood-parasitised. Like other passerine birds, the common chiffchaff can also acquire intestinal nematode parasites and external ticks. The main effect of humans on this species is indirect, through woodland clearance which affects the habitat, predation by cats, and