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"
Mistle thrush Mistle thrush The mistle thrush ("Turdus viscivorus") is a bird common to much of Europe, Asia and North Africa. It is a year-round resident in a large part of its range, but northern and eastern populations migrate south for the winter, often in small flocks. It is a large thrush with pale grey-brown upper parts, a greyish-white chin and throat, and black spots on its pale yellow and off-white under parts. The sexes are similar in plumage, and its three subspecies show only minimal differences. The male has a loud, far-carrying song which is delivered even in wet and windy