Song thrush thrush recognizes the cuckoo's non-mimetic eggs. However, the song thrush does not demonstrate the same aggression toward the adult cuckoo that is shown by the blackbird. The introduced birds in New Zealand, where the cuckoo does not occur, have, over the past 130 years, retained the ability to recognise and reject non-mimetic eggs. Adult birds may be killed by cats, little owls and sparrowhawks, and eggs and nestlings are taken by magpies, jays, and, where present, grey squirrels. As with other passerine birds, parasites are common, and include endoparasites, such as the nematode "Splendidofilaria (Avifilaria) mavis" whose specific name "mavis"
Abyssinian ground thrush Immature birds tend to be paler and duller than the adults. They measure 19–20 cm in length and weigh 43–65g. The contact call of the Abyssinian ground thrush is a high pitched "tseep", the song is a typical thrush like melodious series of whistled phrases rendered in Sinclair & Ryan as "chee-cheeleeroo-chruup". There are six currently recognised subspecies of Abyssinian ground thrush and they are listed below with their distributions: The Abyssinian ground thrush occurs in the undergrowth of evergreen montane forest in high rainfall regions between 1800m and 3300m, mostly above 2500m, although occasionally found lower. May also occur