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"
True thrush genus "Turdus": True thrush True thrushes are medium-sized mostly insectivorous or omnivorous birds in the genus Turdus of the wider thrush family, Turdidae. The genus name "Turdus" is Latin for "thrush". The term "thrush" is used for many other birds of the family Turdidae as well as for a number of species belonging to several other families (see Thrush). The genus has a cosmopolitan distribution, with species in the Americas, Europe, Asia, Africa and Australia. Several species have also colonised some oceanic islands, and two species have been introduced to New Zealand. Some New World species are called robins, the